Chuck Lever [Mon, 25 May 2026 16:51:22 +0000 (12:51 -0400)]
net/handshake: Drain pending requests at net namespace exit
The arguments to list_splice_init() in handshake_net_exit() are
reversed. The call moves the local empty "requests" list onto
hn->hn_requests, leaving the local list empty, so the subsequent
drain loop runs zero iterations. Pending handshake requests that
had not yet been accepted are not torn down when the net namespace
is destroyed; each one keeps a reference on a socket file and on
the handshake_req allocation.
Pass the source and destination in the documented order
(list_splice_init(list, head) moves list onto head) so the pending
list is transferred to the local scratch list and drained through
handshake_complete().
Fixing the splice direction exposes a list-corruption race. After
the splice each req->hr_list still has non-empty link pointers,
threading the stack-local scratch list rather than hn_requests.
A concurrent handshake_req_cancel() -- for example, from sunrpc's
TLS timeout on a kernel socket whose netns reference was not
taken -- finds the request through the rhashtable, calls
remove_pending(), and sees !list_empty(&req->hr_list).
__remove_pending_locked() then list_del_init()s an entry off the
scratch list while the drain iterates, corrupting it. The same
call arriving after the drain loop has run list_del() on an
entry hits LIST_POISON instead.
Have remove_pending() check HANDSHAKE_F_NET_DRAINING under
hn_lock and report not-found when drain is in progress. The
drain has already taken ownership; handshake_complete()'s existing
test_and_set on HANDSHAKE_F_REQ_COMPLETED still arbitrates
between drain and cancel for who calls the consumer's hp_done. Use
list_del_init() rather than list_del() in the drain so req->hr_list
does not carry LIST_POISON after drain releases the entry.
The DRAINING guard in remove_pending() makes cancel return false,
but cancel still falls through to test_and_set_bit on
HANDSHAKE_F_REQ_COMPLETED and drops the request's hr_file reference.
Without another pin, if that is the last reference, sk_destruct frees
the request while it is still linked on the drain loop's local list.
Pin each request's hr_file under hn_lock before releasing the list,
and drop that drain pin after the loop finishes with the request.
Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Hannes Reinecke <hare@kernel.org> Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-8-66c616906ead@oracle.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Chuck Lever [Mon, 25 May 2026 16:51:21 +0000 (12:51 -0400)]
net/handshake: Verify file-reference balance in submit paths
The new file-reference contract on struct handshake_req is silently
breakable: a missing get_file() at submit or a missing fput() on an
error path leaves the file leaked but does not crash the test, so
the existing absence-of-crash checks pass either way.
Snapshot file_count(filp) before each handshake_req_submit() in
the submit-success, EAGAIN, EBUSY, and cancel tests, and assert
the expected balance after submit and again after cancel. The
already-completed cancel test also asserts the post-complete
balance, which pins down that handshake_complete() drops the
reference and that the subsequent cancel does not double-fput.
The destroy test gets the same treatment before __fput_sync(),
which double-checks that cancel's fput() ran and the only
remaining reference is the one sock_alloc_file() established.
Chuck Lever [Mon, 25 May 2026 16:51:20 +0000 (12:51 -0400)]
net/handshake: Close the submit-side sock_hold race
handshake_req_submit() publishes the request via
handshake_req_hash_add() and __add_pending_locked(), drops
hn_lock, and calls handshake_genl_notify() (which can sleep)
before taking sock_hold() on req->hr_sk. A fast tlshd ACCEPT
followed by DONE can drive handshake_complete()'s sock_put()
into the window between the spin_unlock and the late
sock_hold(); on a system where the consumer's fd held the
only sk reference, the late sock_hold() then operates on an
sk whose refcount has reached zero.
The preceding two patches install an explicit file reference
on struct handshake_req. That file pins sock->file, which
pins the embedded struct socket, which defers inet_release()'s
sock_put(). As long as hr_file is held, sk cannot reach refcount
zero from the consumer side, and the submit-side sock_hold()
with its matching sock_put() calls in handshake_complete() and
handshake_req_cancel() is now redundant.
Drop all three. The file reference already keeps each request's
socket alive, and the lifetime story is contained in a single
get_file()/fput() pair.
Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Hannes Reinecke <hare@kernel.org> Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-6-66c616906ead@oracle.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Chuck Lever [Mon, 25 May 2026 16:51:19 +0000 (12:51 -0400)]
net/handshake: hand off the pinned file reference to accept_doit
handshake_req_next() removes the request from the per-net
pending list and drops hn_lock before handshake_nl_accept_doit()
reads req->hr_sk->sk_socket and dereferences sock->file (once in
FD_PREPARE() and again in get_file()). In that window a
consumer running tls_handshake_cancel() followed by sockfd_put()
(svc_sock_free) or __fput_sync() (xs_reset_transport) releases
sock->file. sock_release() then runs sock_orphan(), zeroing
sk_socket, and frees the struct socket. The accept-side code
either reads NULL through sk_socket or chases freed memory.
The submit-side sock_hold() does not prevent this. sk_refcnt
protects struct sock, but struct socket and sock->file are
independently refcounted via the file descriptor the consumer
owns. Pinning sk leaves sock and sock->file unprotected.
Retarget the accept-side dereferences at req->hr_file, which was
pinned at submit time, instead of req->hr_sk->sk_socket->file.
Pinning on its own is not sufficient: a consumer that cancels
between handshake_req_next() returning and accept_doit reaching
FD_PREPARE() takes the !remove_pending() branch in
handshake_req_cancel() and drops hr_file before the accept side
takes its own reference. Hand off an additional file reference
inside handshake_req_next(), under hn_lock, so the accept side
operates on a reference that no concurrent handshake_req_cancel()
can revoke. FD_PREPARE() consumes that handed-off reference,
either by transferring it to the new fd in fd_publish() or by
dropping it in the cleanup destructor on error; the explicit
get_file() that previously balanced FD_PREPARE() is therefore
redundant and goes away.
Update handshake_req_cancel_test2 and _test3 to simulate the
FD_PREPARE() consumption with an fput() so the kunit file-count
assertions stay balanced.
Reported-by: Chris Mason <clm@meta.com> Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Hannes Reinecke <hare@kernel.org> Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-5-66c616906ead@oracle.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Chuck Lever [Mon, 25 May 2026 16:51:18 +0000 (12:51 -0400)]
net/handshake: Take a long-lived file reference at submit
handshake_nl_accept_doit() needs the file pointer backing
req->hr_sk->sk_socket to survive the window between
handshake_req_next() and the subsequent FD_PREPARE() and get_file().
The submit-side sock_hold() does not provide that. sk_refcnt keeps
struct sock alive, but struct socket is owned by sock->file: when
the consumer fputs the last file reference, sock_release() tears
the socket down regardless of any sock_hold.
Add an hr_file pointer to struct handshake_req and acquire an
explicit reference on sock->file during handshake_req_submit().
handshake_complete() and handshake_req_cancel() release the
reference on the completion-bit-winning path.
The submit error path must also release the file reference, but
after rhashtable insertion a concurrent handshake_req_cancel() can
discover the request and race the error path. Gate the error-path
cleanup -- sk_destruct restoration, fput, and request destruction
-- with test_and_set_bit(HANDSHAKE_F_REQ_COMPLETED), the same
serialization handshake_complete() and handshake_req_cancel()
already use. When cancel has already claimed ownership, the submit
error path returns without touching the request; socket teardown
handles final destruction.
The accept-side dereferences are not yet retargeted; that change
comes in the next patch.
Chuck Lever [Mon, 25 May 2026 16:51:17 +0000 (12:51 -0400)]
net/handshake: Pass negative errno through handshake_complete()
handshake_complete() declares status as unsigned int and
tls_handshake_done() negates that value (-status) before handing
it to the TLS consumer. Consumers match on negative errno
constants -- xs_tls_handshake_done() has
switch (status) {
case 0:
case -EACCES:
case -ETIMEDOUT:
lower_transport->xprt_err = status;
break;
default:
lower_transport->xprt_err = -EACCES;
}
so the API as designed expects callers to pass positive errno
values that the tlshd shim then negates.
Three internal callers in handshake_nl_accept_doit(), the
net-exit drain, and a kunit test follow kernel convention and
pass negative errnos -- -EIO, -ETIMEDOUT, -ETIMEDOUT. The
implicit conversion to unsigned int turns -ETIMEDOUT into
0xFFFFFF92; the subsequent -status in tls_handshake_done()
wraps back to 110, the consumer's switch falls through, and
the xprt reports -EACCES on what should be -ETIMEDOUT or -EIO.
Fix the API rather than the call sites. The natural kernel
convention is negative errno in, negative errno out. Change
handshake_complete() and hp_done to take int status, drop the
negation in tls_handshake_done(), and negate once in
handshake_nl_done_doit() where status arrives from the wire
as an unsigned netlink attribute. The three internal callers
were already correct under that convention and need no change.
At the same wire boundary, declare MAX_ERRNO as the netlink
policy upper bound for HANDSHAKE_A_DONE_STATUS. Attribute
validation rejects out-of-range values before
handshake_nl_done_doit() runs, and negating a bounded u32 there
stays within int range -- closing the UBSAN-visible signed-
integer overflow that an unconstrained u32 would invoke.
Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Hannes Reinecke <hare@kernel.org> Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-3-66c616906ead@oracle.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Chuck Lever [Mon, 25 May 2026 16:51:16 +0000 (12:51 -0400)]
nvme-tcp: store negative errno in queue->tls_err
nvme_tcp_tls_done() assigns queue->tls_err in three branches. The
ENOKEY lookup failure and the EOPNOTSUPP initializer both store
negative errnos. The third branch, reached when the handshake
layer reports a non-zero status, stores -status.
The handshake layer delivers status to the consumer callback as a
negative errno; the other in-tree consumers --
xs_tls_handshake_done() and the nvmet target callback -- treat
their status argument that way. The extra negation in
nvme_tcp_tls_done() flips the sign, leaving tls_err as a positive
value (for instance, +EIO), which nvme_tcp_start_tls() then
returns to its caller.
Drop the extra negation so queue->tls_err uniformly carries a
negative errno on failure.
Fixes: be8e82caa685 ("nvme-tcp: enable TLS handshake upcall") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Hannes Reinecke <hare@kernel.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-2-66c616906ead@oracle.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Chuck Lever [Mon, 25 May 2026 16:51:15 +0000 (12:51 -0400)]
net/handshake: Use spin_lock_bh for hn_lock
nvmet_tcp_state_change(), a socket callback that runs in BH context,
can reach handshake_req_cancel() via nvmet_tcp_schedule_release_queue()
and tls_handshake_cancel(). handshake_req_cancel() acquires
hn->hn_lock with plain spin_lock(). If a process-context thread on
the same CPU holds hn->hn_lock when a softirq invokes the cancel path,
the lock attempt deadlocks. This is the only caller that invokes
tls_handshake_cancel() from BH context; every other consumer calls it
from process context.
Deferring the cancel to process context in the NVMe target is not
straightforward: nvmet_tcp_schedule_release_queue() must call
tls_handshake_cancel() atomically with its state transition to
DISCONNECTING. If the cancel were deferred, the handshake completion
callback could fire in the window before the cancel runs, observe the
unexpected state, and return without dropping its kref on the queue.
Reworking that interlock is considerably more invasive than hardening
the handshake lock. Convert all hn->hn_lock acquisitions from
spin_lock/spin_unlock to spin_lock_bh/spin_unlock_bh so the lock is
never taken with softirqs enabled.
Minh Nguyen [Tue, 26 May 2026 04:12:39 +0000 (11:12 +0700)]
net: skbuff: fix missing zerocopy reference in pskb_carve helpers
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy
the old skb_shared_info header into a new buffer via memcpy(), which
includes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs.
Neither function calls net_zcopy_get() for the new shinfo, creating an
unaccounted holder: every skb_shared_info with destructor_arg set will
call skb_zcopy_clear() once when freed, but the corresponding
net_zcopy_get() was never called for the new copy. Repeated calls
drive uarg->refcnt to zero prematurely, freeing ubuf_info_msgzc while
TX skbs still hold live destructor_arg pointers.
KASAN reports use-after-free on a freed ubuf_info_msgzc:
BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810
Read of size 8 at addr ffff88801574d3e8 by task poc/220
Allocated by task 219:
msg_zerocopy_realloc+0x157/0x7b0
tcp_sendmsg_locked+0x2892/0x3ba0
Freed by task 219:
ip_recv_error+0x74a/0xb10
tcp_recvmsg+0x475/0x530
The skb consuming the late access still referenced the same uarg via
shinfo->destructor_arg copied by pskb_carve_inside_nonlinear() without
a refcount bump. This has been verified to be reliably exploitable: a
working proof-of-concept achieves full root privilege escalation from
an unprivileged local user on a default kernel configuration.
The fix follows the pattern of pskb_expand_head() which has the same
memcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get()
is placed after skb_orphan_frags() succeeds, so the orphan error path
needs no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is
placed after all failure points and just before skb_release_data(), so
no error path needs cleanup at all -- matching pskb_expand_head() more
closely and avoiding the need for a balancing net_zcopy_put().
Fixes: 6fa01ccd8830 ("skbuff: Add pskb_extract() helper function") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-sonnet-4-6 Signed-off-by: Minh Nguyen <minhnguyen.080505@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260526041240.329462-1-minhnguyen.080505@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This series fixes an RX packet corruption issue observed when SMMU is
disabled on the hibmcge driver. The fixes include disabling PCI Relaxed
Ordering and correcting the order of DMA barrier operations in the RX
data sync path.
====================
Jijie Shao [Mon, 25 May 2026 14:45:25 +0000 (22:45 +0800)]
net: hibmcge: move dma_rmb() after dma_sync_single_for_cpu() in RX path
The dma_rmb() barrier was placed before dma_sync_single_for_cpu(), which
is incorrect. DMA sync must complete first to make the buffer accessible
to the CPU, then the rmb barrier ensures subsequent descriptor reads
observe the latest data written by the hardware.
Reorder the operations so dma_sync_single_for_cpu() is called before
dma_rmb() to guarantee the driver reads consistent data from the DMA
buffer.
Jijie Shao [Mon, 25 May 2026 14:45:24 +0000 (22:45 +0800)]
net: hibmcge: disable Relaxed Ordering to fix RX packet corruption
When SMMU is disabled, the hibmcge driver may receive corrupted packets.
The hardware writes packet data and descriptors to the same page, but
with Relaxed Ordering enabled, PCI write transactions may not be
strictly ordered. This can cause the driver to observe a valid
descriptor before the corresponding packet data is fully written.
Fix this by clearing PCI_EXP_DEVCTL_RELAX_EN in the PCI bridge control
register to ensure strict write ordering between packet data and
descriptors.
====================
net/sched: Fix packet loops in mirred and netem
This patchset adds a 2-bit per-skb tc_depth counter that travels with
the packet. The existing per-CPU mirred nest tracking loses state
when a packet is deferred through the backlog or moves between CPUs
via XPS/RPS. A per-skb field covers both cases.
Patch 1 adds the tc_depth field in a padding hole in sk_buff.
Patches 2-3 revert the check_netem_in_tree() fix and its tests,
which broke legitimate multi-netem configurations.
Patch 4 uses tc_depth to stop netem duplicate recursion.
Patch 5 uses tc_depth to catch mirred ingress redirect loops.
Patch 6 fixes the infinite loop in the mirred egress blockcast case.
Patch 7 fixes drop stats in early return error scenarios in tcf_mirred_act
for redirect (caught by Sashiko [1]).
Patches 8-9 add mirred and netem test cases.
Victor Nogueira [Mon, 25 May 2026 12:25:56 +0000 (08:25 -0400)]
selftests/tc-testing: Add netem test case exercising loops
Add a netem nested duplicate test case to validate that it won't
cause an infinite loop
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260525122556.973584-10-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260525122556.973584-9-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Victor Nogueira [Mon, 25 May 2026 12:25:54 +0000 (08:25 -0400)]
net/sched: act_mirred: Fix return code in early mirred redirect error paths
Since retval is set as TC_ACT_STOLEN in the mirred redirect case, returning
retval in cases where redirect failed will make the callers not register
the skb as being dropped.
Fix this by returning TC_ACT_SHOT instead in such scenarios.
Fixes: 16085e48cb48 ("net/sched: act_mirred: Create function tcf_mirred_to_dev and improve readability") Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://sashiko.dev/#/patchset/20260413082027.2244884-1-hxzene%40gmail.com Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260525122556.973584-8-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net/sched: act_mirred: Fix blockcast recursion bypass leading to stack overflow
tcf_mirred_act() checks sched_mirred_nest against MIRRED_NEST_LIMIT (4)
to prevent deep recursion. However, when the action uses blockcast
(tcfm_blockid != 0), the function returns at the tcf_blockcast() call
BEFORE reaching the counter increment. As a result, the recursion
counter never advances and the limit check is entirely bypassed.
When two devices share a TC egress block with a mirred blockcast rule,
a packet egressing on device A is mirrored to device B via blockcast;
device B's egress TC re-enters tcf_mirred_act() via blockcast and
mirrors back to A, creating an unbounded recursion loop:
This recursion continues until the kernel stack overflows.
The bug is reachable from an unprivileged user via
unshare(CLONE_NEWUSER | CLONE_NEWNET): user namespaces grant
CAP_NET_ADMIN in the new network namespace, which is sufficient to
create dummy devices, attach clsact qdiscs with shared blocks, and
install mirred blockcast filters.
BUG: TASK stack guard page was hit at ffffc90000b7fff8
Oops: stack guard page: 0000 [#1] SMP KASAN NOPTI
CPU: 2 UID: 1000 PID: 169 Comm: poc Not tainted 7.0.0-rc7-next-20260410
RIP: 0010:xas_find+0x17/0x480
Call Trace:
xa_find+0x17b/0x1d0
tcf_mirred_act+0x640/0x1060
tcf_action_exec+0x400/0x530
basic_classify+0x128/0x1d0
tcf_classify+0xd83/0x1150
tc_run+0x328/0x620
__dev_queue_xmit+0x797/0x3100
tcf_mirred_to_dev+0x7b1/0xf70
tcf_mirred_act+0x68a/0x1060
[repeating ~30+ times until stack overflow]
Kernel panic - not syncing: Fatal exception in interrupt
Fix this by incrementing sched_mirred_nest before calling
tcf_blockcast() and decrementing it on return, mirroring the
non-blockcast path. This ensures subsequent recursive entries see the
updated counter and are correctly limited by MIRRED_NEST_LIMIT.
When mirred redirects to ingress (from either ingress or egress) the loop
state from sched_mirred_dev array dev is lost because of 1) the packet
deferral into the backlog and 2) the fact the sched_mirred_dev array is
cleared. In such cases, if there was a loop we won't discover it.
Here's a simple test to reproduce:
ip a add dev port0 10.10.10.11/24
tc qdisc add dev port0 clsact
tc filter add dev port0 egress protocol ip \
prio 10 matchall action mirred ingress redirect dev port1
tc qdisc add dev port1 clsact
tc filter add dev port1 ingress protocol ip \
prio 10 matchall action mirred egress redirect dev port0
ping -c 1 -W0.01 10.10.10.10
Fixes: fe946a751d9b ("net/sched: act_mirred: add loop detection") Tested-by: Victor Nogueira <victor@mojatatu.com> Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260525122556.973584-6-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Jamal Hadi Salim [Mon, 25 May 2026 12:25:51 +0000 (08:25 -0400)]
net/sched: fix packet loop on netem when duplicate is on
When netem duplicates a packet it re-enqueues the copy at the root qdisc.
If another netem sits in the tree the copy can be duplicated
again, recursing until the stack or memory is exhausted.
The original duplication guard temporarily zeroed q->duplicate around
the re-enqueue, but that does not cover all cases because it is
per-qdisc state shared across all concurrent enqueue paths
and is not safe without additional locking.
Use the skb tc_depth field introduced in an earlier patch:
- increment it on the duplicate before re-enqueue
- skip duplication for any skb whose tc_depth is already non-zero.
This marks the packet itself rather than mutating qdisc state,
therefore it is safe regardless of tree topology or concurrency.
Fixes: 0afb51e72855 ("[PKT_SCHED]: netem: reinsert for duplication") Reported-by: William Liu <will@willsroot.io> Reported-by: Savino Dicanosa <savy@syst3mfailure.io> Closes: https://lore.kernel.org/netdev/8DuRWwfqjoRDLDmBMlIfbrsZg9Gx50DHJc1ilxsEBNe2D6NMoigR_eIRIG0LOjMc3r10nUUZtArXx4oZBIdUfZQrwjcQhdinnMis_0G7VEk=@willsroot.io/ Co-developed-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Reviewed-by: William Liu <will@willsroot.io> Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260525122556.973584-5-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The original patch rejects any tree containing two netems when
either has duplication set, even when they sit on unrelated classes
of the same classful parent. That broke configurations that have
worked since netem was introduced.
The re-entrancy problem the original commit was trying to solve is
handled by later patch using tc_depth flag.
Doing this revert will (re)expose the original bug with multiple
netem duplication. When this patch is backported make sure
and get the full series.
Fixes: ec8e0e3d7ade ("net/sched: Restrict conditions for adding duplicating netems to qdisc tree") Reported-by: Ji-Soo Chung <jschung2@proton.me> Reported-by: Gerlinde <lrGerlinde@mailfence.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220774 Reported-by: zyc zyc <zyc199902@zohomail.cn> Closes: https://lore.kernel.org/all/19adda5a1e2.12410b78222774.9191120410578703463@zohomail.cn/ Reported-by: Manas Ghandat <ghandatmanas@gmail.com> Closes: https://lore.kernel.org/netdev/f69b2c8f-8325-4c2e-a011-6dbc089f30e4@gmail.com/ Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260525122556.973584-3-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Jamal Hadi Salim [Mon, 25 May 2026 12:25:48 +0000 (08:25 -0400)]
net: Introduce skb tc depth field to track packet loops
Add a 2-bit per-skb tc depth field to track packet loops across the stack.
The previous per-CPU loop counters like MIRRED_NEST_LIMIT
assume a single call stack and lose state in two cases:
1) When a packet is queued and reprocessed later (e.g., egress->ingress
via backlog), the per-cpu state is gone by the time it is dequeued.
2) With XPS/RPS a packet may arrive on one CPU and be processed on
another.
A per-skb field solves both by travelling with the packet itself.
The field fits in existing padding, using 2 bits that were previously a
hole:
- /* XXX 2 bits hole, try to pack */
/* XXX 1 byte hole, try to pack */
__u16 tc_index; /* 134 2 */
There used to be a ttl field which was removed as part of tc_verd in commit aec745e2c520 ("net-tc: remove unused tc_verd fields"). It was already
unused by that time, due to remove earlier in commit c19ae86a510c ("tc: remove
unused redirect ttl").
The first user of this field is netem, which increments tc_depth on
duplicated packets before re-enqueueing them at the root qdisc. On
re-entry, netem skips duplication for any skb with tc_depth already set,
bounding recursion to a single level regardless of tree topology.
The other user is mirred which increments it on each pass
and limits to depth to MIRRED_DEFER_LIMIT (3).
The new field was called ttl in earlier versions of this patch
but renamed to tc_depth to avoid confusion with IP ttl.
Note (looking at you Sashiko! Dont ignore me and continue bringing this up):
1. Since both mirred and netem utilize the same 2-bit tc_depth field it is
possible when netem and mirred are used together that netem qdisc to skip
the duplication step. This is a known trade-off, as a 2-bit field cannot
independently track both features' recursion depths and it is not considered
sane to have a setup that addresses both features on at the same time.
2. skb_scrub_packet does not clear tc_depth. This means a packet's loop history
is preserved even across namespaces. While this might be restrictive for
some topologies, it is also design intent to provide robustness against loops
across namespaces.
hdrlen is __u8. For n >= 127 the result exceeds 255 and silently
truncates. With n=127 (cmpri=15, cmpre=15, pad=0, hdrlen=16):
(128 * 16) >> 3 = 256, truncated to 0 as __u8
The caller in ipv6_rpl_srh_rcv() then places the compressed header
at buf + ((ohdr->hdrlen + 1) << 3). With hdrlen=0 this is buf + 8,
but the decompressed region occupies buf[0..2055] (8-byte header
plus 128 full addresses). The compressed header overlaps the
decompressed data, and ipv6_rpl_srh_compress() writes into this
overlap, corrupting the routing header of the forwarded packet.
The existing guard at exthdrs.c:546 checks (n + 1) > 255, which
prevents n+1 from overflowing unsigned char (the segments_left
field), but does not prevent the computed hdrlen from overflowing
__u8. n=127 passes because 128 <= 255, yet hdrlen=256 does not
fit.
Tighten the bound to (n + 1) > 127. This caps n at 126, giving
hdrlen = (127 * 16) >> 3 = 254, which fits in __u8. The compressed
header then lands at buf + ((254 + 1) << 3) = buf + 2040, exactly
past the decompressed region (buf[0..2039]). No overlap. 127
segments is well beyond any realistic RPL deployment.
Jakub Kicinski [Thu, 28 May 2026 00:42:18 +0000 (17:42 -0700)]
Merge branch 'ethtool-more-bug-fixes'
Jakub Kicinski says:
====================
ethtool: more bug fixes
Last week I sent two patch sets - one fixing bugs in RSS handling,
and one fixing CMIS / module handling. This set contains the remaining
fixes. There's a concentration of fixes around PHY and timestamp config
handling but not enough to break those out as separate sets.
====================
Jakub Kicinski [Tue, 26 May 2026 15:35:33 +0000 (08:35 -0700)]
ethtool: eeprom: add more safeties to EEPROM Netlink fallback
The Netlink fallback path for reading module EEPROM
(fallback_set_params()) validates that offset < eeprom_len,
but does not check that offset + length stays within eeprom_len.
The ioctl equivalent (ethtool_get_any_eeprom() in ioctl.c) has
always enforced both bounds:
if (eeprom.offset + eeprom.len > total_len)
return -EINVAL;
This could lead to surprises in both drivers and device FW.
Add the missing offset + length validation to fallback_set_params(),
mirroring the ioctl.
Similarly - ethtool core in general, and ethtool_get_any_eeprom()
in particular tries to zero-init all buffers passed to the drivers
to avoid any extra work of zeroing things out. eeprom_fallback()
uses a plain kmalloc(), change it to zalloc.
Fixes: 96d971e307cc ("ethtool: Add fallback to get_module_eeprom from netlink command") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-11-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:32 +0000 (08:35 -0700)]
ethtool: eeprom: add missing ethnl_ops_begin() / _complete() during fallback
All ethtool driver op calls should be sandwiched between
ethnl_ops_begin() / ethnl_ops_complete(). In Netlink eeprom code,
if the paged access failed we fall back to old API, but we
first call _complete() and the fallback never does its own
ethnl_ops_begin(). Move the fallback into the _begin() / _complete()
section.
Fixes: 96d971e307cc ("ethtool: Add fallback to get_module_eeprom from netlink command") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-10-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:31 +0000 (08:35 -0700)]
ethtool: strset: fix header attribute index in ethnl_req_get_phydev()
strset_prepare_data() passes ETHTOOL_A_HEADER_FLAGS (3) as the header
attribute to ethnl_req_get_phydev(). This is incorrect, in the main
attr space 3 is ETHTOOL_A_STRSET_COUNTS_ONLY, not the request
header attr. The correct constant is ETHTOOL_A_STRSET_HEADER (1).
ethnl_req_get_phydev() only uses this value for the extack,
so this is not a "functionally visible"(?) bug.
Fixes: e96c93aa4be9 ("net: ethtool: strset: Allow querying phy stats by index") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-9-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:30 +0000 (08:35 -0700)]
ethtool: tsinfo: don't pass ERR_PTR to genlmsg_cancel on prepare failure
The goto err label leads to:
genlmsg_cancel(skb, ehdr);
return ret;
If ethnl_tsinfo_prepare_dump() failed, it has not started a genlmsg.
There's nothing to cancel, and passing an error pointer to
genlmsg_cancel() would cause a crash.
Fixes: b9e3f7dc9ed9 ("net: ethtool: tsinfo: Enhance tsinfo to support several hwtstamp by net topology") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Kory Maincent <kory.maincent@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-8-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:29 +0000 (08:35 -0700)]
ethtool: tsinfo: fix uninitialized stats on the by-PHC path
tsinfo_prepare_data() has two code paths: a "by-PHC" path for
user-specified hardware timestamping providers, and the old path.
Commit 89e281ebff72 ("ethtool: init tsinfo stats if requested") added
ethtool_stats_init() to mark stat slots as ETHTOOL_STAT_NOT_SET before
the driver callback populates them, but placed the call inside the
old-path block.
When commit b9e3f7dc9ed9 ("net: ethtool: tsinfo: Enhance tsinfo to
support several hwtstamp by net topology") added the by-PHC early
return, it landed above the stats initialization. On that path
the stats array retains the zero-fill from ethnl_init_reply_data()'s
zalloc. This leads to the reply including a stats nest with four
zero-valued attributes that should have been absent.
Reject GET requests for stats with HWTSTAMP_PROVIDER or dump.
Fixes: b9e3f7dc9ed9 ("net: ethtool: tsinfo: Enhance tsinfo to support several hwtstamp by net topology") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-7-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:27 +0000 (08:35 -0700)]
ethtool: pse-pd: fix missing ethnl_ops_complete()
pse_prepare_data() is missing ethnl_ops_complete() if
ethnl_req_get_phydev() returned an error. Move getting
phydev up so that we don't have to worry about this
(similar order to linkstate_prepare_data()).
Note that phydev may still be NULL (this is checked in
pse_get_pse_attributes()), the goal isn't really to avoid
the _begin() / _complete() calls, only to simplify the error
handling.
While at it propagate the original error. Why this code
overrides the error with -ENODEV but !phydev generates
-EOPNOTSUPP is unclear to me...
Fixes: 31748765bed3 ("net: ethtool: pse-pd: Target the command to the requested PHY") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-5-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:26 +0000 (08:35 -0700)]
ethtool: linkstate: fix unbalanced ethnl_ops_complete() on PHY lookup error
linkstate_prepare_data() calls ethnl_req_get_phydev() before
ethnl_ops_begin(), but routes its error path through "goto out"
which calls ethnl_ops_complete().
Fixes: fe55b1d401c6 ("ethtool: linkstate: migrate linkstate functions to support multi-PHY setups") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-4-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:25 +0000 (08:35 -0700)]
ethtool: tsconfig: fix reply error handling
A couple of trivial bugs in error handling in tsconfig_send_reply().
If we failed to allocate rskb we need to set the error.
If we did allocate it but failed to send it - we need to remember
to free it.
Fixes: 6e9e2eed4f39 ("net: ethtool: Add support for tsconfig command to get/set hwtstamp config") Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Reviewed-by: Kory Maincent <kory.maincent@bootlin.com> Link: https://patch.msgid.link/20260526153533.2779187-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Tue, 26 May 2026 15:35:24 +0000 (08:35 -0700)]
ethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES
ethnl_update_profile() walks the ETHTOOL_A_PROFILE_IRQ_MODERATION
nest list with an index 'i' and writes new_profile[i++] without
bounding i. The destination is kmemdup()'d at NET_DIM_PARAMS_NUM_PROFILES
entries (5), but the Netlink nest count is entirely user-controlled.
Netlink policies do not have support for constraining the number
of nested entries (or number of multi-attr entries).
Jakub Kicinski [Thu, 28 May 2026 00:23:07 +0000 (17:23 -0700)]
Merge branch 'bridge-fix-sleep-in-atomic-context'
Ido Schimmel says:
====================
bridge: Fix sleep in atomic context
Under certain circumstances the bridge driver can call
dev_set_promiscuity() while holding the bridge spin lock. This is a
problem as dev_set_promiscuity() might sleep.
Patches #1-#2 fix the problem in the netlink and sysfs configuration
paths by only taking the lock where it is actually needed, thereby
avoiding calling dev_set_promiscuity() from an atomic context.
Patch #3 adds test cases for both configuration paths in rtnetlink.sh
which already includes test cases for similar issues.
Note that dev_set_promiscuity() can sleep either when it takes the net
device mutex or when calling netif_rx_mode_sync(). I encountered the
problem with the latter, but blamed the former since it came earlier.
====================
Add two test cases that always pass, but trigger sleeping in atomic
context BUGs without "bridge: Fix sleep in atomic context in netlink
path" and "bridge: Fix sleep in atomic context in sysfs path".
Ido Schimmel [Tue, 26 May 2026 06:48:17 +0000 (09:48 +0300)]
bridge: Fix sleep in atomic context in sysfs path
Since the start of the git history, brport_store() always acquired the
bridge lock. Back then this decision made sense: The bridge lock
protects the STP state of the bridge and its ports and at that time the
function was only used by two STP related attributes (cost and
priority).
Nowadays, brport_store() processes a lot more attributes and most of
them do not need the bridge lock:
* Bridge flags: Only require RTNL. Read locklessly by the data path.
Annotations can be added in net-next.
* FDB port flushing: Only requires the FDB lock.
* Multicast attributes: Only require the multicast lock.
* Group forward mask: Only requires RTNL. Read locklessly by the data
path. Annotations can be added in net-next.
* Backup port: Only requires RTNL. Read locklessly by the data path.
This is a problem as the bridge calls dev_set_promiscuity() when certain
bridge port flags change and this function can sleep since the commit
cited below, resulting in a splat such as [1].
Fix this by reducing the scope of the bridge lock and only take it when
processing the two STP related attributes that require it. Remove the
now stale comment from br_switchdev_set_port_flag(). The
SWITCHDEV_F_DEFER flag can be removed in net-next.
Ido Schimmel [Tue, 26 May 2026 06:48:16 +0000 (09:48 +0300)]
bridge: Fix sleep in atomic context in netlink path
Since the introduction of the netlink configuration path for bridge
ports in commit 25c71c75ac87 ("bridge: bridge port parameters over
netlink"), br_setport() was always called with the bridge lock held
around it. Back then this decision made sense: The bridge lock protects
the STP state of the bridge and its ports and at that time the function
only processed three STP related netlink attributes (cost, priority and
state).
Nowadays, br_setport() processes a lot more attributes and most of them
do not need the bridge lock:
* Bridge flags: Only require RTNL. Read locklessly by the data path.
Annotations can be added in net-next.
* FDB port flushing: Only requires the FDB lock.
* Multicast attributes: Only require the multicast lock.
* Group forward mask: Only requires RTNL. Read locklessly by the data
path. Annotations can be added in net-next.
* Backup port and NHID: Only require RTNL. Read locklessly by the data
path.
This is a problem as the bridge calls dev_set_promiscuity() when certain
bridge port flags change and this function can sleep since the commit
cited below, resulting in a splat such as [1].
Fix this by reducing the scope of the bridge lock and only take it when
processing the three STP related attributes that require it. This is
consistent with the multicast attributes where each attribute acquires
the multicast lock instead of having one critical section for all
relevant attributes.
Oliver Hartkopp [Tue, 26 May 2026 19:33:19 +0000 (21:33 +0200)]
bonding: refuse to enslave CAN devices
syzbot reported a kernel paging request crash in
can_rx_unregister() inside net/can/af_can.c. The crash occurs
because a virtual CAN device (vxcan) is being enslaved to a
bonding master.
During the enslavement process, the bonding driver mutates
and modifies the network device states to fit an Ethernet-like
aggregation model. However, CAN devices operate on a completely
different Layer 2 architecture, relying on the CAN mid-layer
private data structure (can_ml_priv) instead of standard
Ethernet structures. Since bonding does not initialize or
maintain these CAN structures, subsequent operations on the
half-enslaved interface (such as closing associated sockets
via isotp_release) lead to a null-pointer dereference when
accessing the CAN receiver lists.
Bonding CAN interfaces is architecturally invalid as CAN lacks
MAC addresses, ARP capabilities, and standard Ethernet
link-layer mechanisms. While generic loopback devices are
blocked globally in net/core/dev.c, virtual CAN devices
bypass this check because they do not carry the IFF_LOOPBACK
flag, despite acting as local software-loopbacks.
Fix this by explicitly blocking network devices of type
ARPHRD_CAN from being enslaved at the very beginning of
bond_enslave(). This prevents illegal state mutations,
eliminates the resulting KASAN crashes, and avoids potential
memory leaks from incomplete socket cleanups.
As the CAN support has been added a long time after bonding
the Fixes-tag points to the introduction of ARPHRD_CAN that
would have needed a specific handling in bonding_main.c.
Fixes: cd05acfe65ed ("[CAN]: Allocate protocol numbers for PF_CAN") Reported-by: syzbot+8ed98cbd0161632bce95@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8ed98cbd0161632bce95 Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Acked-by: Jay Vosburgh <jv@jvosburgh.net> Link: https://patch.msgid.link/20260526-bonding-candev-v1-1-ba1df400918a@hartkopp.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Qi Tang [Sat, 23 May 2026 14:32:45 +0000 (22:32 +0800)]
ipv6: validate extension header length before copying to cmsg
ip6_datagram_recv_specific_ctl() builds IPV6_{HOPOPTS,DSTOPTS,RTHDR}
cmsgs (and their IPV6_2292* legacy counterparts) by trusting the
on-wire hdrlen byte (ptr[1]) when computing the put_cmsg() length.
The length was validated only at parse time (ipv6_parse_hopopts(),
etc.). An nftables payload-write expression can rewrite hdrlen after
parsing and before the skb reaches recvmsg; the write itself is
in-bounds but put_cmsg() then reads up to ((hdrlen+1) << 3) = 2040
bytes from an 8-byte header. nftables is reachable from an
unprivileged user namespace, so this is an unprivileged
slab-out-of-bounds read:
BUG: KASAN: slab-out-of-bounds in put_cmsg+0x3ac/0x540
put_cmsg+0x3ac/0x540
udpv6_recvmsg+0xca0/0x1250
sock_recvmsg+0xdf/0x190
____sys_recvmsg+0x1b1/0x620
Add ipv6_get_exthdr_len() which validates that at least two bytes
are accessible before reading the hdrlen field, then checks the
computed length against skb_tail_pointer(skb), returning 0 on
failure. Extension headers are kept in the linear skb area by
pskb_may_pull() during input, so skb_tail_pointer() is the correct
bound.
Use ipv6_get_exthdr_len() at all non-AH call sites: the five
standalone cmsg blocks (HbH, 2292HbH, 2292DSTOPTS x2, 2292RTHDR)
and the three standard cases in the extension-header walk loop
(DSTOPTS, ROUTING, default). AH retains an inline bounds check
because its length formula differs ((ptr[1]+2)<<2).
The walk loop also gets a pre-read bounds check at the top to
validate ptr before any case accesses ptr[0] or ptr[1].
When the walk loop detects a corrupted header, return from the
function instead of continuing to process later socket options.
Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Qi Tang <tpluszz77@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260523143245.2281415-1-tpluszz77@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Wed, 27 May 2026 01:32:34 +0000 (18:32 -0700)]
Merge tag 'nfc-7.1-rc6' of https://codeberg.org/linux-nfc/linux
David Heidelberg says:
====================
nfc pull request for net:
Code improvements
- llcp: Fix use-after-free in llcp_sock_release()
- llcp: Fix use-after-free race in nfc_llcp_recv_cc()
- hci: fix out-of-bounds read in HCP header parsing
Regression fixes:
- nxp-nci: i2c: use rising-edge IRQ on ACPI systems
Signed-off-by: David Heidelberg <david@ixit.cz>
* tag 'nfc-7.1-rc6' of https://codeberg.org/linux-nfc/linux:
nfc: nxp-nci: i2c: use rising-edge IRQ on ACPI systems
nfc: hci: fix out-of-bounds read in HCP header parsing
nfc: llcp: Fix use-after-free race in nfc_llcp_recv_cc()
nfc: llcp: Fix use-after-free in llcp_sock_release()
====================
Eric Dumazet [Mon, 25 May 2026 20:36:42 +0000 (20:36 +0000)]
vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()
skb_tunnel_check_pmtu() can change skb->head.
Reusing old_iph afer skb_tunnel_check_pmtu() can cause an UAF.
Use instead ip_hdr(skb) as done in drivers/net/bareudp.c
and drivers/net/geneve.c.
Found by Sashiko.
Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Link: https://patch.msgid.link/20260525203642.2389723-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Eric Dumazet [Mon, 25 May 2026 20:13:35 +0000 (20:13 +0000)]
tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]()
Sashiko found that iptunnel_pmtud_build_icmp() and
iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr()
before an skb_cow() call which can reallocate skb->head.
Fix this possible UAF by initializing the local variables
after the skb_cow() call.
Remove skb_reset_network_header() calls which were not needed.
Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Link: https://patch.msgid.link/20260525201335.2361845-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Lucien.Jheng [Sun, 24 May 2026 06:39:15 +0000 (14:39 +0800)]
net: phy: air_en8811h: add AN8811HB MCU assert/deassert support
AN8811HB needs a MCU soft-reset cycle before firmware loading begins.
Assert the MCU (hold it in reset) and immediately deassert (release)
via a dedicated PBUS register pair (0x5cf9f8 / 0x5cf9fc), accessed
through a registered mdio_device at PHY-addr+8.
Add __air_pbus_reg_write() as a low-level helper taking a struct
mdio_device *, create and register the PBUS mdio_device in
an8811hb_probe() and store it in priv->pbusdev, then implement
an8811hb_mcu_assert() / _deassert() on top of it. Add
an8811hb_remove() to unregister the PBUS device on teardown. Wire
both calls into an8811hb_load_firmware() and en8811h_restart_mcu()
so every firmware load or MCU restart on AN8811HB correctly sequences
the reset control registers.
l2tp: use refcount_inc_not_zero in l2tp_session_get_by_ifname
A reader in l2tp_session_get_by_ifname() can return a pointer to a
session whose refcount has reached zero. The getter takes its
reference with plain refcount_inc(), but every other session getter
in the same file (l2tp_v2_session_get, l2tp_v3_session_get, and the
corresponding _get_next variants) uses refcount_inc_not_zero()
because the IDR/RCU lookup can race with refcount_dec_and_test() ->
l2tp_session_free() -> kfree_rcu(). The ifname getter is the only
outlier; the inconsistency was raised on-list after 979c017803c4
("l2tp: use list_del_rcu in l2tp_session_unhash").
A reader inside rcu_read_lock_bh() that matches session->ifname can
be preempted between the strcmp() and the refcount_inc(). If the
last reference drops on another CPU in that window, the reader's
refcount_inc() runs on a counter that has reached zero. refcount_t
catches the addition-on-zero, prints "refcount_t: addition on 0;
use-after-free", saturates the counter, and returns the saturated
pointer to the caller. Session memory is held live by the in-flight
RCU read section, but the kfree_rcu() callback queued from
l2tp_session_free() will free it once the grace period closes; a
caller that dereferences the returned session past that point hits
a slab-use-after-free. On PREEMPT_RT local_bh_disable() is a per-CPU
sleeping lock and the preemption window is real; on stock PREEMPT
kernels local_bh_disable() is a preempt_count increment that closes
the cross-CPU race in practice (see below).
Use refcount_inc_not_zero() and continue the list walk on failure,
matching the other session getters in the file. The ifname getter
is the only session getter in net/l2tp/ that still uses the bare
refcount_inc() pattern; this change restores file-internal
consistency. The success path is unchanged.
Fixes: abe7a1a7d0b6 ("l2tp: improve tunnel/session refcount helpers") Cc: stable@vger.kernel.org Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Reviewed-by: James Chapman <jchapman@katalix.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260523023423.2568972-1-michael.bommarito@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
ethtool: module: fix a handful of small bugs
I've been poking at the locking in ethtool and it appears
that the FW flashing is not currently taking the ops lock.
Existing drivers which implement module FW flashing seem
to have their own locking, so this series doesn't actually
add the ops lock (I'll add it in net-next). But a number
of other errors have been surfaced in the process.
====================
Jakub Kicinski [Fri, 22 May 2026 23:13:12 +0000 (16:13 -0700)]
ethtool: cmis: validate fw->size against start_cmd_payload_size
cmis_fw_update_start_download() copies start_cmd_payload_size bytes
from the firmware blob into the CDB LPL vendor_data[] payload without
validating that the FW has enough data.
Since the start_cmd_payload_size can only be ~120B an image too short
is most likely corrupted, so reject it.
Fixes: c4f78134d45c ("ethtool: cmis_fw_update: add a layer for supporting firmware update using CDB") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Link: https://patch.msgid.link/20260522231312.1710836-10-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Fri, 22 May 2026 23:13:11 +0000 (16:13 -0700)]
ethtool: cmis: validate start_cmd_payload_size from module
The CMIS firmware update code reads start_cmd_payload_size from
the module's FW Management Features CDB reply and uses it directly
as the byte count for memcpy. The destination buffer is 112 bytes
(ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH - 8). So a malicious
module (or corrupted response) can cause a OOB write later on in
cmis_fw_update_start_download().
Let's error out. If modules that expect longer LPL writes actually
exist we should revisit.
struct cmis_cdb_start_fw_download_pl's definition has to move,
no change there.
Fixes: c4f78134d45c ("ethtool: cmis_fw_update: add a layer for supporting firmware update using CDB") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Link: https://patch.msgid.link/20260522231312.1710836-9-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Fri, 22 May 2026 23:13:10 +0000 (16:13 -0700)]
ethtool: cmis: fix u16-to-u8 truncation of msleep_pre_rpl
ethtool_cmis_cdb_compose_args() accepts msleep_pre_rpl as u16 but stores
it into the u8 field ethtool_cmis_cdb_cmd_args::msleep_pre_rpl, silently
truncating values >= 256. Seven of the nine call sites pass 1000 ms
(it's the third argument from the end).
Fixes: a39c84d79625 ("ethtool: cmis_cdb: Add a layer for supporting CDB commands") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Link: https://patch.msgid.link/20260522231312.1710836-8-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Fri, 22 May 2026 23:13:09 +0000 (16:13 -0700)]
ethtool: cmis: require exact CDB reply length
Malicious SFP module could respond with rpl_len longer than
what cmis_cdb_process_reply() expected, leading to OOB writes.
Malicious HW is a bit theoretical but some modules may just
be buggy and/or the reads may occasionally get corrupted,
so let's protect the kernel.
The existing check protects from short replies. We need to
protect from long ones, too. All callers that pass a non-zero
rpl_exp_len cast the reply payload to a fixed-layout struct
and read fields at fixed offsets, with no version negotiation
or short-reply handling:
so let's assume that responses longer than expected do not
have to be handled gracefully here. Add a warning message
to make the debug easier in case my understanding is wrong...
Note that page_data->length (argument of kmalloc) comes from
last arg to ethtool_cmis_page_init() which is rpl_exp_len.
Note2 that AIs also like to point out overflows in args->req.payload
itself (which is a fixed-size 120 B buffer, on the stack),
but callers should be reading structs defined by the standard,
so protecting from requests for more data than max seem like
defensive programming.
Jakub Kicinski [Fri, 22 May 2026 23:13:08 +0000 (16:13 -0700)]
ethtool: module: fix cleanup if socket used for flashing multiple devices
When a single Netlink socket issues MODULE_FW_FLASH_ACT against multiple
devices, ethnl_sock_priv_set() overwrites sk_priv->dev on each call,
retaining only the last one. The socket priv is used on socket close,
to walk the global work list and mark the uncompleted flashing work
as "orphaned". Otherwise if another socket reuses the PID it will
unexpectedly receive the flashing notifications.
Don't record the device, record net pointer instead. The purpose of
the dev is to scope the work to a netns, anyway. If we store netns
the overrides are safe/a nop since all flashed devices must be in
the same netns as the socket.
Jakub Kicinski [Fri, 22 May 2026 23:13:07 +0000 (16:13 -0700)]
ethtool: module: check fw_flash_in_progress under rtnl_lock
ethnl_set_module_validate() inspects module_fw_flash_in_progress
but validate is meant for _input_ validation, not state validation.
rtnl_lock is not held, yet. Move the check into ethnl_set_module().
Fixes: 32b4c8b53ee7 ("ethtool: Add ability to flash transceiver modules' firmware") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Link: https://patch.msgid.link/20260522231312.1710836-5-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Fri, 22 May 2026 23:13:06 +0000 (16:13 -0700)]
ethtool: module: avoid racy updates to dev->ethtool bitfield
When reviewing other changes Gemini points out that we currently
update module_fw_flash_in_progress without holding any locks.
Since module_fw_flash_in_progress is part of a bitfield this
is not great, updates to other fields may be lost.
We could use a bool and sprinkle some READ_ONCE/WRITE_ONCE here
but seems like the issue is rather than the work is an unusual
writer. The other writers already hold the right locks. So just
very briefly take these locks when the work completes.
Note that nothing ever cancels the FW update work, so there's
no concern with deadlocks vs cancel.
Fixes: 32b4c8b53ee7 ("ethtool: Add ability to flash transceiver modules' firmware") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Link: https://patch.msgid.link/20260522231312.1710836-4-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Fri, 22 May 2026 23:13:05 +0000 (16:13 -0700)]
ethtool: module: avoid leaking a netdev ref on module flash errors
module_flash_fw_schedule() is missing undo for setting
the "in_progress" flag and taking the netdev reference.
Delay taking these, the device can't disappear while
we are holding rtnl_lock.
Fixes: 32b4c8b53ee7 ("ethtool: Add ability to flash transceiver modules' firmware") Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Danielle Ratson <danieller@nvidia.com> Link: https://patch.msgid.link/20260522231312.1710836-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Fri, 22 May 2026 23:06:47 +0000 (16:06 -0700)]
ethtool: rss: avoid device context leak on reply-build failure
We wait with filling the reply for new RSS context creation
until after the driver ->create_rxfh_context call. The driver
needs to fill some of the defaults in the context. The failure
of rss_fill_reply() is somewhat theoretical, but doesn't take
much effort to handle it properly. Call ->remove_rxfh_context().
If the driver's remove callback fails (some implementations like sfc
can return real command errors from firmware RPCs) - skip the xa_erase
and kfree, leaving the context in the xarray. This matches how
ethnl_rss_delete_doit() behaves.
Jakub Kicinski [Fri, 22 May 2026 23:06:46 +0000 (16:06 -0700)]
ethtool: rss: fix hkey leak when indir_size is 0
rss_get_data_alloc() allocates a single buffer that backs both the
indirection table and the hash key, but only assigned data->indir_table
when indir_size was nonzero. The expectation was that no driver
implements RSS without supporting indirection table but apparently
enic does just that (it's the only such in-tree driver).
enic has get_rxfh_key_size but no get_rxfh_indir_size.
data->indir_table stays as NULL, hkey gets set but rss_get_data_free()
kfree(data->indir_table) is a nop and the allocation leaks.
Always store the allocation base in data->indir_table so the free path
is unambiguous. No caller treats indir_table as a sentinel; everything
keys off indir_size.
Jakub Kicinski [Fri, 22 May 2026 23:06:45 +0000 (16:06 -0700)]
ethtool: rss: fix indir_table and hkey leak on get_rxfh failure
rss_prepare_get() allocates the indirection table and hash key buffer
via rss_get_data_alloc(), then calls ops->get_rxfh() to populate them.
If get_rxfh() fails, the function returns an error without freeing
the allocation.
rss_set_prep_indir() compares the new indirection table against the
current one to determine whether any update is needed. The memcmp
call passes data->indir_size as the length argument, but indir_size
is the number of u32 entries, not the byte count.
Jakub Kicinski [Fri, 22 May 2026 23:06:42 +0000 (16:06 -0700)]
ethtool: rss: avoid modifying the RSS context response
Gemini says that we're modifying the RSS_CREATE response skb.
I think it's right, the comment says that unicast() should
unshare the skb but I'm not entirely sure what I meant there.
netlink_trim() does a copy but only if skb is not well sized
(it's at least 2x larger than necessary for the payload).
Björn Töpel [Fri, 22 May 2026 12:06:40 +0000 (14:06 +0200)]
net: Avoid checksumming unreadable skb tail on trim
pskb_trim_rcsum_slow() keeps CHECKSUM_COMPLETE valid by subtracting
the checksum of the bytes removed from the skb tail. That assumes the
removed bytes can be read.
io_uring zcrx skbs may contain unreadable net_iov frags. With fbnic
header/data split, small TCP/IPv4 packets can carry Ethernet padding
in such a frag. ip_rcv_core() trims the skb to iph->tot_len before TCP
sees it, and the CHECKSUM_COMPLETE adjustment then calls
skb_checksum() on the padding.
This is exposed by IPv4 because small TCP/IPv4 frames can be shorter
than the Ethernet minimum payload. TCP/IPv6 frames are large enough in
the normal zcrx path, so they do not hit the same padding trim.
Keep the existing checksum adjustment for readable skbs. If the
remaining packet is fully linear, drop CHECKSUM_COMPLETE and let the
stack validate the packet after trimming. If unreadable payload would
remain, fail the trim; the checksum cannot be adjusted without reading
the trimmed tail.
Also clear skb->unreadable when trimming removes all frags.
Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags") Signed-off-by: Björn Töpel <bjorn@kernel.org> Reviewed-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/20260522120643.242974-1-bjorn@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
====================
ip6_vti: vti6_changelink and vti6_siocdevprivate netns fixes
1/2 carries forward Eric Dumazet's Reviewed-by. Only the Fixes
tag changes there. 2/2 changes the Fixes tag and adds the
ns_capable hunk.
====================
Maoyi Xie [Thu, 21 May 2026 13:05:55 +0000 (21:05 +0800)]
ip6: vti: Use ip6_tnl.net in vti6_siocdevprivate().
After patch 1/2 in this series, vti6_update() unlinks and relinks
the tunnel through t->net. vti6_siocdevprivate() still uses
dev_net(dev) for the collision lookup. For a tunnel moved through
IFLA_NET_NS_FD, dev_net(dev) is the new netns, not t->net.
SIOCCHGTUNNEL on a migrated tunnel then runs:
net = dev_net(dev) /* migrated netns */
t = vti6_locate(net, &p1, false) /* misses target in t->net */
...
t = netdev_priv(dev)
vti6_update(t, &p1, false) /* mutates t->net's hash */
A caller in the migrated netns picks params that match a tunnel
in the creation netns. The lookup in dev_net(dev) finds nothing.
vti6_update() prepends the migrated tunnel at the head of the
creation netns hash bucket for those params. Later lookups in
the creation netns resolve to the migrated device. xfrm receive
delivers the matched packets through a device the caller controls.
Reachable from an unprivileged user namespace (unshare --user
--map-root-user --net). Cross tenant scope on container hosts.
Switch the SIOCCHGTUNNEL path on a non fallback device to use
t->net for the lookup. The lookup now matches the netns
vti6_update() operates on.
Also add ns_capable(self->net->user_ns, CAP_NET_ADMIN) before
the lookup. The check at the top of the case is against
dev_net(dev)->user_ns, which after migration is the attacker's
netns. A caller there can pick params absent from self->net,
the lookup returns NULL, t becomes self, and vti6_update()
inserts the device into the creation netns hash. The new check
requires CAP_NET_ADMIN in the creation netns user_ns too.
SIOCADDTUNNEL and SIOCCHGTUNNEL on the fallback device keep
dev_net(dev), which equals init_net there.
ip netns add ns1
ip netns add ns2
ip -n ns1 link add vti6_test type vti6 remote ::1 local ::2 key 7
ip -n ns1 link set vti6_test netns ns2
ip -n ns2 link set vti6_test type vti6 remote ::3 local ::4 key 9
ip netns del ns2
ip netns del ns1
[ 132.495484] ------------[ cut here ]------------
[ 132.497609] kernel BUG at net/core/dev.c:12376!
Commit 61220ab34948 ("vti6: Enable namespace changing") dropped
NETIF_F_NETNS_LOCAL from vti6 devices. A vti6 tunnel can then
move through IFLA_NET_NS_FD. After the move dev_net(dev) points
at the new netns while t->net stays at the creation netns.
vti6_changelink() and vti6_update() still use dev_net(dev) and
dev_net(t->dev). They unlink from one per netns hash and relink
into another. The creation netns is left with a stale entry.
cleanup_net() of that netns later walks freed memory.
Reachable from an unprivileged user namespace (unshare --user
--map-root-user --net). Cross tenant scope on container hosts.
Weiming Shi [Thu, 21 May 2026 08:12:01 +0000 (01:12 -0700)]
net: team: fix NULL pointer dereference in team_xmit during mode change
__team_change_mode() clears team->ops with memset() before restoring
safe dummy handlers via team_adjust_ops(). A concurrent team_xmit()
running under RCU on another CPU can read team->ops.transmit during
this window and call a NULL function pointer, crashing the kernel.
The race requires a mode change (CAP_NET_ADMIN) concurrent with
transmit on the team device.
The original code assumed that no ports means no traffic, so mode
changes could freely memset()/memcpy() the ops. AF_PACKET with
forced carrier breaks that assumption.
Prevent the race instead of making it safe: replace memset()/memcpy()
with per-field updates that never touch transmit or receive. Those
two handlers are managed solely by team_adjust_ops(), which already
installs dummies when tx_en_port_count == 0 (always true during mode
change since no ports are present). WRITE_ONCE/READ_ONCE prevent
store/load tearing on the handler pointers.
synchronize_net() before exit_op() drains in-flight readers that may
still reference old mode state from before port removal switched the
handlers to dummies.
Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260521081159.1491563-3-bestswngs@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Luka Gejak [Sat, 23 May 2026 13:03:30 +0000 (15:03 +0200)]
net: hsr: fix potential OOB access in supervision frame handling
Ensure the entire TLV header is linearized before access by adding
sizeof(struct hsr_sup_tlv) to the pskb_may_pull() calls. Without this,
a truncated frame could cause an out-of-bounds access.
Fixes: eafaa88b3eb7 ("net: hsr: Add support for redbox supervision frames") Signed-off-by: Luka Gejak <luka.gejak@linux.dev> Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de> Link: https://patch.msgid.link/20260523130330.61880-1-luka.gejak@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify
rvu_mbox_handler_rep_event_notify() in drivers/net/ethernet/marvell/
octeontx2/af/rvu_rep.c queues a sender-controlled REP_EVENT_NOTIFY
request body verbatim, and rvu_rep_up_notify() then forwards
event->pcifunc (the nested body field, distinct from the
AF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and
the AF->PF mailbox device index without any bounds check.
A VF attached to a PF that has been put into switchdev
representor mode reaches this path: the VF mailbox handler
otx2_pfvf_mbox_handler() forwards every message id including
MBOX_MSG_REP_EVENT_NOTIFY to AF without an allowlist, and the AF
dispatcher rewrites only msg->pcifunc, leaving struct
rep_event::pcifunc attacker-controlled. The sibling
rvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc
is not rvu->rep_pcifunc; this handler has no equivalent gate.
An out-of-range body pcifunc selects an &rvu->pf[]/&rvu->hwvf[]
element past the allocated array and, for RVU_EVENT_MAC_ADDR_CHANGE,
turns into a six-byte attacker-chosen OOB ether_addr_copy() target
inside the queued worker; KASAN reports a slab-out-of-bounds write
in rvu_rep_wq_handler.
Reject malformed requests at the handler entry by gating on
is_pf_func_valid(), which is already the canonical PF/VF range check
in this driver; expose it via rvu.h so callers in rvu_rep.c can use
it instead of open-coding the same range arithmetic.
Fixes: b8fea84a0468 ("octeontx2-pf: Add support to sync link state between representor and VFs") Cc: stable@vger.kernel.org Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Link: https://patch.msgid.link/20260520154157.1439319-1-michael.bommarito@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Junrui Luo [Wed, 20 May 2026 03:47:55 +0000 (11:47 +0800)]
macsec: fix replay protection at XPN lower-PN wrap
In macsec_post_decrypt(), when pn is U32_MAX, pn + 1 overflows u32 to 0
and the first branch never fires. If next_pn_halves.lower is also in the
upper half, pn_same_half(pn, lower) is true and the XPN else-if does not
fire either, leaving next_pn_halves unchanged. An attacker that captures
the legitimate frame carrying pn == 0xFFFFFFFF on an XPN association
can then replay it indefinitely, since lowest_pn never rises above
the captured pn and macsec_decrypt() reconstructs the same IV.
Extend the XPN else-if to also fire when pn + 1 wraps to 0, so receipt
of pn == U32_MAX advances next_pn_halves to (upper + 1, 0).
Zhengchuan Liang [Fri, 22 May 2026 09:42:26 +0000 (17:42 +0800)]
ipv6: exthdrs: refresh nh after handling HAO option
ip6_parse_tlv() caches skb_network_header(skb) in nh while walking
IPv6 TLVs.
ipv6_dest_hao() may call pskb_expand_head() for a cloned skb, which can
move the skb head and invalidate the cached network header pointer.
Refresh nh after ipv6_dest_hao() returns so any trailing padding or TLVs
are parsed from the current skb head.
This matches the existing pattern used in ip6_parse_tlv() after helpers
that can modify skb header storage.
Jakub Kicinski [Mon, 25 May 2026 17:37:27 +0000 (10:37 -0700)]
Merge tag 'nf-26-05-22' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Florian Westphal says:
====================
netfilter: updates for net
Patches 7+8 fix a regression from 7.1-rc1. Everything else
is from 2.6.x to 5.3 releases. There are additional known
issues with these patches (drive-by-findings in related code).
There are many old bugs all over netfilter and our ability to review
feature patches has come to a complete halt due to lack of time.
There are further security bugs that we cannot address
due to lack of time, maintainers and reviewers.
Other remarks: The xtables 32bit compat interface is already
off in many vendor kernels, the plan is to remove it soon.
1) Prevent RST packets with invalid sequence numbers from forcing TCP
connections into the CLOSE state without a direction check.
From Hamza Mahfooz.
2) Re-derive the TCP header pointer after skb_ensure_writable in
synproxy_tstamp_adjust. Prevent use-after-free and invalid checksum
updates caused by stale pointers during buffer expansion.
From Chris Mason.
3) Fix a race condition causing keymap list corruption in conntracks gre/pptp
helper.
4) Use raw_smp_processor_id() in xt_cpu to prevent splats under
PREEMPT_RCU.
5) Disable netfilter payload mangling in user namespaces (nft_payload.c
and nf_queue).
TCP option mangling via nft_exthdr.c remains enabled.
There will be followups here to restrict resp. revalidate
headers.
6) Fix an out-of-bounds read in ebtables's compat_mtw_from_user function.
7) Use list_for_each_entry_rcu() to traverse fib6_siblings in
nft_fib6_info_nh_uses_dev(). Ensure safe list walking under RCU.
8) Fix an out-of-bounds read in nft_fib_ipv6 caused by incorrect list
traversal.
9) Add nft_fib_nexthop selftest to netfilter. Cover nexthop enumeration for
single, group, and multipath route shapes.
All three nft_fib6 fixes from Jiayuan Chen.
10) Fix destination corruption in shift operations when source and destination
registers overlap. Reject partial register overlap for all operations
from control plane. From Fernando Fernandez Mancera.
* tag 'nf-26-05-22' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nf_tables: fix dst corruption in same register operation
selftests: netfilter: add nft_fib_nexthop test
netfilter: nft_fib_ipv6: handle routes via external nexthop
netfilter: nft_fib_ipv6: walk fib6_siblings under RCU
netfilter: ebtables: fix OOB read in compat_mtw_from_user
netfilter: disable payload mangling in userns
netfilter: xt_cpu: prefer raw_smp_processor_id
netfilter: nf_conntrack_gre: fix gre keymap list corruption
netfilter: synproxy: refresh tcphdr after skb_ensure_writable
netfilter: conntrack: tcp: do not force CLOSE on invalid-seq RST without direction check
====================
mlx5_cmd_hws_packet_reformat_alloc() handles
MLX5_REFORMAT_TYPE_REMOVE_HDR by looking up a matching HWS remove-header
action.
If mlx5_fs_get_action_remove_header_vlan() returns NULL, the code only
logs an error and continues. The function then returns success with a NULL
HWS action stored in the packet-reformat object.
Return an error when no matching remove-header action is available.
vsock/virtio: fix skb overhead overflow on 32-bit builds
On 32-bit architectures, both skb_queue_len() and SKB_TRUESIZE(0) evaluate
to 32-bit values. The multiplication can overflow before being assigned to
the u64 skb_overhead variable, making the skb overhead check ineffective.
Cast skb_queue_len() to u64 so the multiplication is always performed in
64-bit arithmetic.
This issue was reported by Sashiko while reviewing another patch.
Fixes: 059b7dbd20a6 ("vsock/virtio: fix potential unbounded skb queue") Closes: https://sashiko.dev/#/patchset/20260518090656.134588-1-sgarzare%40redhat.com Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://patch.msgid.link/20260521124732.125771-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Breno Leitao [Thu, 21 May 2026 14:11:45 +0000 (07:11 -0700)]
net/iucv: fix locking in .getsockopt
Mirror iucv_sock_setsockopt() and wrap the whole switch in
lock_sock()/release_sock(). The pre-existing SO_MSGLIMIT-only lock
becomes redundant and is removed.
Any AF_IUCV HIPER user can potentially crash the kernel by racing
recvmsg() with getsockopt(SO_MSGSIZE): the SO_MSGSIZE arm dereferences
iucv->hs_dev->mtu after iucv_sock_close() (called from the racing
recvmsg()) has set hs_dev to NULL, producing a NULL pointer dereference
oops.
Suggested-by: Stanislav Fomichev <sdf.kernel@gmail.com> Fixes: 51363b8751a6 ("af_iucv: allow retrieval of maximum message size") Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Tested-by: Alexandra Winter <wintera@linux.ibm.com> Link: https://patch.msgid.link/20260521-af_iucv_fix2-v1-1-f16b1c510aa9@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alexandra Winter [Thu, 21 May 2026 14:56:39 +0000 (16:56 +0200)]
net/smc: Do not re-initialize smc hashtables
INIT_HLIST_HEAD(&smc_v*_hashinfo.ht) are called after smc_nl_init(),
proto_register() and sock_register(). This can lead to smc_v*_hashinfo.ht
being reset even though hash entries already exist and are being used,
possibly resulting in a corrupted list.
Remove unnecessary and dangerous re-initialisation of smc_v*_hashinfo.ht in
smc_init(); it is implicitly initialised to zero anyhow. Add
HLIST_HEAD_INIT to the definitions for clarity.
Fixes: f16a7dd5cf27 ("smc: netlink interface for SMC sockets") Suggested-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexandra Winter <wintera@linux.ibm.com> Acked-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com> Link: https://patch.msgid.link/20260521145639.10317-1-wintera@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
netlink: fixes for cross-namespace nsid reporting
While working on some new features for OVS and OVN we discovered that
self-referential NSIDs get unintentionally allocated in the system as
well as unexpectedly reported for local events on all-nsid listeners.
More details in the patches. They change user-visible behavior, but
the current behavior is arguably a bug, as it makes it hard to use
all-nsid sockets without a decent amount of extra unrelated work of
tracking when new NSIDs are allocated for your local namespace.
Tests are added to check the expected behavior and YNL is extended
to support all-nsid sockets in the tests.
====================
Ilya Maximets [Wed, 20 May 2026 17:22:38 +0000 (19:22 +0200)]
selftests: net: add a test case for nsid in all nsid notifications
The test subscribes to link events from all namespaces and makes
sure that local events do not carry NSID in their ancillary data
(even if there is a self-referential NSID allocated for the local
namespace), and remote events do.
Ilya Maximets [Wed, 20 May 2026 17:22:36 +0000 (19:22 +0200)]
net: netlink: don't set nsid on local notifications
In most cases, notifications on sockets with NETLINK_LISTEN_ALL_NSID
do not contain NSID in their ancillary data in case the event is local
to the listener.
However, when a self-referential NSID is allocated for a namespace,
every local notification starts sending this ID to the user space.
This is problematic, because the listener cannot tell if those
notifications are local or not anymore without making extra requests
to figure out if the provided NSID is local or not. The listener
can also not figure out the local NSID beforehand as it can be
allocated at any point in time by other processes, changing the
structure of the future notifications for everyone.
The value is practically not useful, since it's the namespace's own
ID that the application has to obtain from other sources in order to
figure out if it's the same or not. So, for the application it's
just an extra busy work with no benefits. Moreover, applications
that do not know about this quirk may be mishandling notifications
with NSID set as notifications from remote namespaces. This is the
case for ovs-vswitchd and the iproute2's 'ip monitor' that stops
printing 'current' and starts printing the nsid number mid-session.
Lack of clear documentation for this behavior is also not helping.
A search though open-source projects doesn't reveal any projects
that use NETNSA_NSID_NOT_ASSIGNED and rely on metadata to contain
self-referential NSIDs (expected, since the value is not useful).
Quite the opposite, as already mentioned, there are few applications
that rely on NSID to not be present in local events.
Since the value is not useful and actively harmful in some cases,
let's not report it for local events, making the notifications more
consistent.
Also adding some blank lines for readability.
Fixes: 59324cf35aba ("netlink: allow to listen "all" netns") Reported-by: Matteo Perin <matteo.perin@canonical.com> Signed-off-by: Ilya Maximets <i.maximets@ovn.org> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://patch.msgid.link/20260520172317.175168-3-i.maximets@ovn.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Ilya Maximets [Wed, 20 May 2026 17:22:35 +0000 (19:22 +0200)]
net: netlink: fix sending unassigned nsid after assigned one
If the current skb is not shared, it is re-used directly for all the
sockets subscribed to the notification. If we have remote all-nsid
socket receiving a message first, then the 'nsid_is_set' will be
set to 'true'. If the nsid is NOT_ASSIGNED for the next socket in
the list, the 'nsid_is_set' will remain 'true' and the negative value
is be delivered to the user space. All subsequent nsid values will be
delivered as well, since there is no code path that sets the flag
back to 'false'.
Fix that by always dropping the flag to 'false' first.
Ziyu Zhang [Tue, 19 May 2026 16:56:36 +0000 (00:56 +0800)]
vsock: keep poll shutdown state consistent
vsock_poll() reads vsk->peer_shutdown before taking the socket lock
to set EPOLLHUP and EPOLLRDHUP, then reads it again after taking
the lock to report EOF readability. A shutdown packet can update
peer_shutdown while poll is waiting for the lock, so one poll invocation
can report EOF readability without the corresponding HUP/RDHUP bits.
For connectible sockets, take one peer_shutdown snapshot after
lock_sock() and use it for all peer-shutdown-derived poll bits. For
datagram sockets, which do not take lock_sock() in poll(), take one
lockless READ_ONCE() snapshot and pair it with WRITE_ONCE() on the
writer side.
This keeps the peer-shutdown-derived bits internally consistent for each
poll pass.
Weiming Shi [Thu, 21 May 2026 16:33:13 +0000 (09:33 -0700)]
tun: free page on build_skb failure in tun_xdp_one()
When build_skb() fails in tun_xdp_one(), the function sets ret to
-ENOMEM and jumps to the out label, which returns without freeing the
page that vhost_net_build_xdp() allocated for the frame. As with the
short-frame rejection path, tun_sendmsg() discards the per-buffer error
and still returns total_len, so vhost_tx_batch() takes the success path
and never frees the page. Each build_skb() failure in a batch leaks one
page-frag chunk.
Free the page before taking the error path, matching the put_page() the
other error exits of tun_xdp_one() already perform.
Fixes: 043d222f93ab ("tuntap: accept an array of XDP buffs through sendmsg()") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260521163312.1479805-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Weiming Shi [Thu, 21 May 2026 16:32:31 +0000 (09:32 -0700)]
tap: free page on error paths in tap_get_user_xdp()
tap_get_user_xdp() rejects a frame shorter than ETH_HLEN with -EINVAL,
and returns -ENOMEM when build_skb() fails. Both paths jump to the err
label without freeing the page that vhost_net_build_xdp() allocated for
the frame. tap_sendmsg() discards the per-buffer return value and always
returns 0, so vhost_tx_batch() takes the success path and never frees
the page; each rejected frame in a batch leaks one page-frag chunk.
Free the page on both error paths, before the skb is built. This is the
tap counterpart of the same leak in tun_xdp_one().
Fixes: 0efac27791ee ("tap: accept an array of XDP buffs through sendmsg()") Fixes: ed7f2afdd0e0 ("tap: add missing verification for short frame") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260521163230.1478627-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Weiming Shi [Wed, 20 May 2026 16:00:21 +0000 (09:00 -0700)]
tun: free page on short-frame rejection in tun_xdp_one()
tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without
freeing the page that vhost_net_build_xdp() allocated for it.
tun_sendmsg() discards that -EINVAL and still returns total_len, so
vhost_tx_batch() takes the success path and never frees the page; each
short frame in a batch leaks one page-frag chunk.
A local process that can open /dev/net/tun and /dev/vhost-net can hit
this path: it attaches a tun/tap device as the vhost-net backend and
feeds TX descriptors whose length minus the virtio-net header is below
ETH_HLEN. Each kick leaks the page-frag chunks for that batch, and a
tight submission loop exhausts host memory and triggers an OOM panic.
Free the page before returning -EINVAL, matching the XDP-program error
path in the same function.
Fixes: 049584807f1d ("tun: add missing verification for short frame") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260520160020.375349-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netfilter: nf_tables: fix dst corruption in same register operation
For lshift and rshift, the shift operations are performed in a loop over
32-bit words. The loop calculates the shifted value and write it to dst,
and then immediately reads from src to calculate the carry for the next
iteration. Because src and dst could point to the same memory location,
the carry is incorrectly calculated using the newly modified dst value
instead of the original src value.
Adding a temporary local variable to cache the original value before
writing to dst and using it for the carry calculation solves the
problem. In addition, partial overlap is rejected from control plane for
all kind of operations including byteorder. This was tested with the
following bytecode:
Jiayuan Chen [Wed, 20 May 2026 02:34:11 +0000 (10:34 +0800)]
selftests: netfilter: add nft_fib_nexthop test
Functional coverage of nft_fib6_eval()'s nexthop enumeration over
three route shapes:
1) single external nexthop (nhid)
2) external nexthop group (nhid -> group)
3) old-style multipath (nexthop ... nexthop ...)
Each scenario places one nexthop on the input device (veth0). For
(2) and (3) the matching nexthop is the second member, so the walk
has to traverse beyond the primary nh. Two nft counters on prerouting
verify the data path: one increments only when fib reports veth0 as
the oif, the other counts "missing" results and must stay at zero.
./nft_fib_nexthop.sh
PASS: single external nexthop (nhid -> veth0)
PASS: nexthop group (dummy0 + veth0)
PASS: old-style multipath (sibling on veth0)
nft_fib6_info_nh_uses_dev() blindly walks &rt->fib6_siblings, causing
an OOB read past the struct nexthop slab when rt->nh is set:
==================================================================
BUG: KASAN: slab-out-of-bounds in nft_fib6_eval+0x1362/0x16c0
Read of size 8 at addr ffff888103a099d0 by task ping/386
Branch by route shape: when rt->nh is set, walk via
nexthop_for_each_fib6_nh() (also covers nh groups, which the original
code missed); otherwise walk fib6_siblings, guarded by READ_ONCE() of
rt->fib6_nsiblings as required by commit 31d7d67ba127 ("ipv6: annotate
data-races around rt->fib6_nsiblings").
Jiayuan Chen [Wed, 20 May 2026 02:34:09 +0000 (10:34 +0800)]
netfilter: nft_fib_ipv6: walk fib6_siblings under RCU
nft_fib6_info_nh_uses_dev() runs from nft_fib6_eval() in softirq under
rcu_read_lock(). fib6_siblings is modified by writers that hold
tb6_lock but do not wait for RCU readers, so the sibling walk should
use list_for_each_entry_rcu(): it adds READ_ONCE() on the ->next
pointer and lets CONFIG_PROVE_RCU_LIST validate the locking.
Florian Westphal [Tue, 19 May 2026 20:52:07 +0000 (22:52 +0200)]
netfilter: ebtables: fix OOB read in compat_mtw_from_user
Luxiao Xu says:
The function compat_mtw_from_user() converts ebtables extensions from
32-bit user structures to kernel native structures. However, it lacks
proper validation of the user-supplied match_size/target_size.
When certain extensions are processed, the kernel-side translation
logic may perform memory accesses based on the extension's expected
size. If the user provides a size smaller than what the extension
requires, it results in an out-of-bounds read as reported by KASAN.
This fix introduces a check to ensure match_size is at least as large
as the extension's required compatsize. This covers matches, watchers,
and targets, while maintaining compatibility with standard targets.
AFAIU this is relevant for matches that need to go though
match->compat_from_user() call. Those that use plain memcpy with the
user-provided size are ok because the caller checks that size vs the
start of the next rule entry offset (which itself is checked vs. total
size copied from userspace).
The ->compat_from_user() callbacks assume they can read compatsize bytes,
so they need this extra check.
Based on an earlier patch from Luxiao Xu.
Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support") Reported-by: Yuan Tan <yuantan098@gmail.com> Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Reported-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Luxiao Xu <rakukuip@gmail.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de> Signed-off-by: Florian Westphal <fw@strlen.de>
Florian Westphal [Sat, 16 May 2026 15:23:21 +0000 (23:23 +0800)]
netfilter: disable payload mangling in userns
Several parts of network stack rely on iph->ihl validation
done by network stack before PRE_ROUTING.
Disable this feature for user namespaces for now.
tcp option handling is likely safe even for LOCAL_IN, so this
this leaves tcp option mangling via nft_exthdr.c as-is.
I don't think these are the only means to alter packets, but these
appear to be relatively prominent.
This could be relaxed later. Example:
- allow userns for ingress hook.
- allow userns if base is transport header.
Also, we should revalidate or restrict generally:
- Don't allow linklayer writes to spill into network header
- restrict ipv4 and ipv6 to 'known safe' writes, e.g.
saddr/daddr/check/tos
Florian Westphal [Thu, 14 May 2026 12:21:57 +0000 (14:21 +0200)]
netfilter: nf_conntrack_gre: fix gre keymap list corruption
Quoting reporter:
A race between GRE keymap insertion and destruction can corrupt the
kernel list or use a freed object. `nf_ct_gre_keymap_add()` publishes a
new keymap pointer before the embedded `list_head` is linked, while
`nf_ct_gre_keymap_destroy()` can concurrently delete and free that
same object. An unprivileged user can reach this through the PPTP
conntrack helper by racing PPTP control messages or helper teardown,
leading to KASAN-detectable list corruption/UAF in kernel context.
## Root Cause Analysis
`exp_gre()` installs GRE expectations for a PPTP control flow and then
adds two GRE keymap entries [..]
The add path publishes `ct_pptp_info->keymap[dir]` before linking the
embedded list node [..]
Concurrent teardown deletes that partially initialized object.
Make add/destroy symmetric: install both, destroy both while under lock.
Furthermore, we should refuse to publish a new mapping in case ct is going
away, else we may leak the allocation.
The "retrans" detection is strange: existing mapping is checked for key
equality with the new mapping, then for "is on the list" via list walk.
But I can't see how an existing keymap entry can be NOT on list.
Change this to only check if we're asked to map same tuple again -- if so,
skip re-install, else signal failure.
Last, add a bug trap for the keymap list; it has to be empty when namespace
is going away.
Reported-by: Leo Lin <leo@depthfirst.com> Signed-off-by: Florian Westphal <fw@strlen.de>
Chris Mason [Tue, 19 May 2026 19:36:14 +0000 (12:36 -0700)]
netfilter: synproxy: refresh tcphdr after skb_ensure_writable
synproxy_tstamp_adjust() rewrites the TCP timestamp option in place
and then patches the TCP checksum via inet_proto_csum_replace4() on
the caller-supplied tcphdr pointer. Both ipv4_synproxy_hook() and
ipv6_synproxy_hook() obtain that pointer with skb_header_pointer()
before calling in, so it may either alias skb->head directly or
point at the caller's on-stack _tcph buffer.
Between obtaining the pointer and using it, the function calls
skb_ensure_writable(skb, optend), which on a cloned or non-linear
skb invokes pskb_expand_head() and frees the old skb->head. After
that point the cached th is stale:
caller (ipv[46]_synproxy_hook)
th = skb_header_pointer(skb, ..., &_tcph)
synproxy_tstamp_adjust(skb, protoff, th, ...)
skb_ensure_writable(skb, optend)
pskb_expand_head() /* kfree(old skb->head) */
...
inet_proto_csum_replace4(&th->check, ...)
/* writes into freed head, or
into the caller's stack copy
leaving the on-wire checksum
stale */
The option bytes are written through skb->data and are fine; only
the checksum update goes through th and so lands in the wrong
place. The result is either a write into freed slab memory or a
packet leaving with a checksum that does not match its payload.
Fix by re-deriving th from skb->data + protoff immediately after
skb_ensure_writable() succeeds, so the subsequent checksum update
targets the linear, writable header.
Hamza Mahfooz [Mon, 11 May 2026 14:43:14 +0000 (10:43 -0400)]
netfilter: conntrack: tcp: do not force CLOSE on invalid-seq RST without direction check
An unintended behavior in the TCP conntrack state machine allows a
connection to be forced into the CLOSE state using an RST packet with an
invalid sequence number.
Specifically, after a SYN packet is observed, an RST with an invalid SEQ
can transition the conntrack entry to TCP_CONNTRACK_CLOSE, regardless of
whether the RST corresponds to the expected reply direction. The relevant
code path assumes the RST is a response to an outgoing SYN, but does not
validate packet direction or ensure that a matching SYN was actually sent
in the opposite direction.
As a result, a crafted packet sequence consisting of a SYN followed by an
invalid-sequence RST can prematurely terminate an active NAT entry. This
makes connection teardown easier than intended.
So, tighten the state transition logic to ensure that RST-triggered
CLOSE transitions only occur when the RST is a valid response to a
previously observed SYN in the correct direction.
Linus Torvalds [Thu, 21 May 2026 21:39:12 +0000 (14:39 -0700)]
Merge tag 'net-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from Bluetooth, wireless and netfilter.
Craziness continues with no end in sight. Even discounting the driver
revert this is a pretty huge PR for standards of the previous era. I'd
speculate - we haven't seen the worst of it, yet. Good news, I guess,
is that so far we haven't seen many (any?) cases of "AI reported a
bug, we fixed it and a real user regressed".
Current release - fix to a fix:
- Bluetooth: btmtk: accept too short WMT FUNC_CTRL events
- vsock/virtio: relax the recently added memory limit a little
Current release - regressions:
- IB/IPoIB: make sure IB drivers always use async set_rx_mode since
some (mlx5) are now required to use it due to locking changes
Previous releases - regressions:
- udp: fix UDP length on last GSO_PARTIAL segment
- af_unix: fix UAF read of tail->len in unix_stream_data_wait()
- tcp: fix stale per-CPU tcp_tw_isn leak enabling ISN prediction
- mlx5e: fix unlocked writing to ICOSQ, breaking AF_XDP
Previous releases - always broken:
- tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
- ipv4: raw: reject IP_HDRINCL packets with ihl < 5
- Bluetooth: a lot of locking and concurrency fixes (as always)
- batman-adv (mesh wireless networking): a lot of random fixes for
issues reported by security researchers and Sashiko
- netfilter: same thing, a lot of small security-ish fixes all over
the place, nothing really stands out
Misc:
- bring back the old 3c509 driver, Maciej wants to maintain it"
* tag 'net-7.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (187 commits)
net: enetc: avoid VF->PF mailbox timeout during SR-IOV teardown
net: enetc: fix init and teardown order to prevent use of unsafe resources
net: enetc: fix unbounded loop and interrupt handling in VF-to-PF messaging
net: enetc: fix DMA write to freed memory in enetc_msg_free_mbx()
net: enetc: fix race condition in VF MAC address configuration
net: enetc: fix TOCTOU race and validate VF MAC address
net: enetc: add ratelimiting to VF mailbox error messages
net: enetc: fix missing error code when pf->vf_state allocation fails
net: enetc: fix incorrect mailbox message status returned to VFs
net: bridge: prevent too big nested attributes in br_fill_linkxstats()
l2tp: use list_del_rcu in l2tp_session_unhash
net: bcmgenet: keep RBUF EEE/PM disabled
ethernet: 3c509: Fix most coding style issues
ethernet: 3c509: Update documentation to match MAINTAINERS
ethernet: 3c509: Add GPL 2.0 SPDX license identifier
ethernet: 3c509: Fix AUI transceiver type selection
Revert "drivers: net: 3com: 3c509: Remove this driver"
tools: ynl: support listening on all nsids
net: gro: don't merge zcopy skbs
pds_core: ensure null-termination for firmware version strings
...
Linus Torvalds [Thu, 21 May 2026 21:17:28 +0000 (14:17 -0700)]
Merge tag 'ceph-for-7.1-rc5' of https://github.com/ceph/ceph-client
Pull ceph fix from Ilya Dryomov:
"A fix for an 'rbd unmap' race condition which popped up on a
production setup where many RBD devices are frequently mapped and
unmapped, marked for stable"
* tag 'ceph-for-7.1-rc5' of https://github.com/ceph/ceph-client:
rbd: eliminate a race in lock_dwork draining on unmap
Linus Torvalds [Thu, 21 May 2026 21:05:09 +0000 (14:05 -0700)]
Merge tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer fixes from Steven Rostedt:
- Fix reporting MISSED EVENTS in trace iterator
When the "trace" file is read with tracing enabled, if the writer
were to pass the iterator reader, it resets, sets a "missed_events"
flag and continues. The tracing output checks for missed events and
if there are some, it prints out "[LOST EVENTS]" to let the user know
events were dropped.
But the clearing of the missed_events happened when the tracing
system queried the ring buffer iterator about missed events. This was
premature as the ring buffer is per CPU, and the tracing code reads
all the CPU buffers and checks for missed events when it is read. If
the CPU iterator that had missed events isn't printed next, the
output for the LOST EVENTS is lost.
Clear the missed_events flag when the iterator moves to the next
event and not when the missed_events flag is queried. Also clear it
on reset.
- Flush and stop the persistent ring buffer on panic
On panic the persistent ring buffer is used to debug what caused the
panic. But on some architectures, it requires flushing the memory
from cache, otherwise, the ring buffer persistent memory may not have
the last events and this could also cause the ring buffer to be
corrupted on the next boot.
- Fix nr_subbufs initialization in simple_ring_buffer_init_mm
The remote simple ring buffer meta data nr_subbufs is initialized too
early and gets cleared later on, making it zero and not reflect the
actual number of sub-buffers.
- Fix unload_page for simple_ring_buffer init rollback
On error, the pages loaded need to be unloaded. To unload a page it
is expected that: page = load_page(va); -> unload_page(page). But the
code was doing: unload_page(va) and not unload_page(page).
- Create output file from cmd_check_undefined
The check for undefined symbols checks if the file *.o.checked exists
and if so it skips doing the work. But the *.o.checked file never was
created making every build do the work even when it was already done
previously.
* tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Create output file from cmd_check_undefined
tracing: Fix unload_page for simple_ring_buffer init rollback
tracing: Fix nr_subbufs initialization in simple_ring_buffer_init_mm()
ring-buffer: Flush and stop persistent ring buffer on panic
ring-buffer: Fix reporting of missed events in iterator
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