Two frag-transfer helpers (__pskb_copy_fclone() and skb_shift()) fail
to propagate the SKBFL_SHARED_FRAG bit in skb_shinfo()->flags when
moving frags from source to destination. __pskb_copy_fclone() defers
the rest of the shinfo metadata to skb_copy_header() after copying
frag descriptors, but that helper only carries over gso_{size,segs,
type} and never touches skb_shinfo()->flags; skb_shift() moves frag
descriptors directly and leaves flags untouched. As a result, the
destination skb keeps a reference to the same externally-owned or
page-cache-backed pages while reporting skb_has_shared_frag() as
false.
The mismatch is harmful in any in-place writer that uses
skb_has_shared_frag() to decide whether shared pages must be detoured
through skb_cow_data(). ESP input is one such writer (esp4.c,
esp6.c), and a single nft 'dup to <local>' rule -- or any other
nf_dup_ipv4() / xt_TEE caller -- is enough to land a pskb_copy()'d
skb in esp_input() with the marker stripped, letting an unprivileged
user write into the page cache of a root-owned read-only file via
authencesn-ESN stray writes.
Set SKBFL_SHARED_FRAG on the destination whenever frag descriptors
were actually moved from the source. skb_copy() and skb_copy_expand()
share skb_copy_header() too but linearize all paged data into freshly
allocated head storage and emerge with nr_frags == 0, so
skb_has_shared_frag() returns false on its own; they need no change.
The same omission exists in skb_gro_receive() and skb_gro_receive_list().
The former moves the incoming skb's frag descriptors into the
accumulator's last sub-skb via two paths (a direct frag-move loop and
the head_frag + memcpy path); the latter chains the incoming skb whole
onto p's frag_list. Downstream skb_segment() reads only
skb_shinfo(p)->flags, and skb_segment_list() reuses each sub-skb's
shinfo as the nskb -- both p and lp must carry the marker.
The same omission also exists in tcp_clone_payload(), which builds an
MTU probe skb by moving frag descriptors from skbs on sk_write_queue
into a freshly allocated nskb. The helper falls into the same family
and warrants the same fix for consistency; no TCP TX-side in-place
writer is currently known to reach a user page through this gap, but
a future consumer depending on the marker would regress silently.
The same omission exists in skb_segment(): the per-iteration flag
merge takes only head_skb's flag, and the inner switch that rebinds
frag_skb to list_skb on head_skb-frags exhaustion does not fold the
new frag_skb's flag into nskb. Fold frag_skb's flag at both sites
so segments drawing frags from frag_list members carry the marker.
Fixes: cef401de7be8 ("net: fix possible wrong checksum generation") Fixes: f4c50a4034e6 ("xfrm: esp: avoid in-place decrypt on shared skb frags") Suggested-by: Sabrina Dubroca <sd@queasysnail.net> Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com> Suggested-by: Ben Hutchings <ben@decadent.org.uk> Suggested-by: Lin Ma <malin89@huawei.com> Suggested-by: Jingguo Tan <tanjingguo@huawei.com> Suggested-by: Aaron Esau <aaron1esau@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Tested-by: Rajat Gupta <rajat.gupta@oss.qualcomm.com> Link: https://patch.msgid.link/ageeJfJHwgzmKXbh@v4bel Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[bwh: Backported to 5.10:
- Set the SKBTX_SHARED_FRAG flag in skb_shared_info::tx_flags,
instead of SKBFL_SHARED_FRAG in skb_shared_info::flags
- skb_gro_receive() and skb_gro_receive_list() are in skbuff.c here
- Drop change to tcp_clone_payload(), which does not exist here
- Adjust context in skb_shift()
] Signed-off-by: Ben Hutchings <benh@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
skb_try_coalesce() can attach paged frags from @from to @to. If @from
has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same
externally-owned or page-cache-backed frags, but the shared-frag marker
is currently lost.
That breaks the invariant relied on by later in-place writers. In
particular, ESP input checks skb_has_shared_frag() before deciding
whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP
receive coalescing has moved shared frags into an unmarked skb, ESP can
see skb_has_shared_frag() as false and decrypt in place over page-cache
backed frags.
Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged
frags. The tailroom copy path does not need the marker because it copies
bytes into @to's linear data rather than transferring frag descriptors.
Fixes: cef401de7be8 ("net: fix possible wrong checksum generation") Fixes: f4c50a4034e6 ("xfrm: esp: avoid in-place decrypt on shared skb frags") Signed-off-by: William Bowling <vakzz@zellic.io> Reviewed-by: Eric Dumazet <edumazet@google.com> Tested-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260513041635.1289541-1-vakzz@zellic.io Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[bwh: Backported to 5.10: Set the SKBTX_SHARED_FRAG flag in
sk_buff::tx_flags, instead of SKBFL_SHARED_FRAG in sk_buff::flags] Signed-off-by: Ben Hutchings <benh@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a synthetic feature flag specifically for first generation Zen
machines. There's need to have a generic flag for all Zen generations so
make X86_FEATURE_ZEN be that flag.
The 'dumpability' of a task is fundamentally about the memory image of
the task - the concept comes from whether it can core dump or not - and
makes no sense when you don't have an associated mm.
And almost all users do in fact use it only for the case where the task
has a mm pointer.
But we have one odd special case: ptrace_may_access() uses 'dumpable' to
check various other things entirely independently of the MM (typically
explicitly using flags like PTRACE_MODE_READ_FSCREDS). Including for
threads that no longer have a VM (and maybe never did, like most kernel
threads).
It's not what this flag was designed for, but it is what it is.
The ptrace code does check that the uid/gid matches, so you do have to
be uid-0 to see kernel thread details, but this means that the
traditional "drop capabilities" model doesn't make any difference for
this all.
Make it all make a *bit* more sense by saying that if you don't have a
MM pointer, we'll use a cached "last dumpability" flag if the thread
ever had a MM (it will be zero for kernel threads since it is never
set), and require a proper CAP_SYS_PTRACE capability to override.
MSG_SPLICE_PAGES can attach pages from a pipe directly to an skb. TCP
marks such skbs with SKBFL_SHARED_FRAG after skb_splice_from_iter(),
so later paths that may modify packet data can first make a private
copy. The IPv4/IPv6 datagram append paths did not set this flag when
splicing pages into UDP skbs.
That leaves an ESP-in-UDP packet made from shared pipe pages looking
like an ordinary uncloned nonlinear skb. ESP input then takes the no-COW
fast path for uncloned skbs without a frag_list and decrypts in place
over data that is not owned privately by the skb.
Mark IPv4/IPv6 datagram splice frags with SKBFL_SHARED_FRAG, matching
TCP. Also make ESP input fall back to skb_cow_data() when the flag is
present, so ESP does not decrypt externally backed frags in place.
Private nonlinear skb frags still use the existing fast path.
This intentionally does not change ESP output. In esp_output_head(),
the path that appends the ESP trailer to existing skb tailroom without
calling skb_cow_data() is not reachable for nonlinear skbs:
skb_tailroom() returns zero when skb->data_len is nonzero, while ESP
tailen is positive. Thus ESP output will either use the separate
destination-frag path or fall back to skb_cow_data().
Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible") Fixes: 7da0dde68486 ("ip, udp: Support MSG_SPLICE_PAGES") Fixes: 6d8192bd69bb ("ip6, udp6: Support MSG_SPLICE_PAGES") Reported-by: Hyunwoo Kim <imv4bel@gmail.com> Reported-by: Kuan-Ting Chen <h3xrabbit@gmail.com> Tested-by: Hyunwoo Kim <imv4bel@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Kuan-Ting Chen <h3xrabbit@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
[bwh: Backported to 5.10: set the SKBTX_SHARED_FRAG flag in
ip_append_page() instead of __ip{,6}_append_data()] Signed-off-by: Ben Hutchings <benh@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
privcmd_vm_ops defines .close (privcmd_close), but neither .may_split
nor .open. When userspace does a partial munmap() on a privcmd mapping,
the kernel splits the VMA via __split_vma(). Since may_split is NULL,
the split is allowed. vm_area_dup() copies vm_private_data (a pages
array allocated in alloc_empty_pages()) into the new VMA without any
fixup, because there is no .open callback.
Both VMAs now point to the same pages array. When the unmapped portion
is closed, privcmd_close() calls:
- xen_unmap_domain_gfn_range()
- xen_free_unpopulated_pages()
- kvfree(pages)
The surviving VMA still holds the dangling pointer. When it is later
destroyed, the same sequence runs again, which leads to a double free.
Fix this issue by adding a .may_split callback denying the VMA split.
The src SG list offset wasn't set properly when decrypting in-place,
fix it.
Reported-by: Wolfgang Walter <linux@stwm.de> Fixes: e02494114ebf ("crypto: authencesn - Do not place hiseq at end of dst for out-of-place decryption") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When decrypting data that is not in-place (src != dst), there is
no need to save the high-order sequence bits in dst as it could
simply be re-copied from the source.
However, the data to be hashed need to be rearranged accordingly.
Reported-by: Taeyang Lee <0wn@theori.io> Fixes: 104880a6b470 ("crypto: authencesn - Convert to new AEAD interface") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
AF_ALG AEAD AIO requests currently use the socket-wide IV buffer during
request processing. For async requests, later socket activity can
update that shared state before the original request has fully
completed, which can lead to inconsistent IV handling.
Snapshot the IV into per-request storage when preparing the AEAD
request, so in-flight operations no longer depend on mutable socket
state.
Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management") Cc: stable@kernel.org 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> Co-developed-by: Luxing Yin <tr0jan@lzu.edu.cn> Signed-off-by: Luxing Yin <tr0jan@lzu.edu.cn> Tested-by: Yucheng Lu <kanolyc@gmail.com> Signed-off-by: Douya Le <ldy3087146292@gmail.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This mostly reverts commit 72548b093ee3 except for the copying of
the associated data.
There is no benefit in operating in-place in algif_aead since the
source and destination come from different mappings. Get rid of
all the complexity added for in-place operation and just copy the
AD directly.
Fixes: 72548b093ee3 ("crypto: algif_aead - copy AAD from src to dst") Reported-by: Taeyang Lee <0wn@theori.io> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function was rewritten twice. The earlier implementations had many
prerequisite commits, while the latest implementation is standalone.
It's much easier to just backport the latest code directly.
[5.10: replaced kmap_local and memcpy_page]
Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix function name in chacha.c kernel-doc comment to remove a warning.
Convert af_alg.c to kernel-doc notation to eliminate many kernel-doc
warnings.
../lib/crypto/chacha.c:77: warning: expecting prototype for chacha_block(). Prototype was for chacha_block_generic() instead
chacha.c:104: warning: Excess function parameter 'out' description in 'hchacha_block_generic'
af_alg.c:498: warning: Function parameter or member 'sk' not described in 'af_alg_alloc_tsgl'
../crypto/af_alg.c:539: warning: expecting prototype for aead_count_tsgl(). Prototype was for af_alg_count_tsgl() instead
../crypto/af_alg.c:596: warning: expecting prototype for aead_pull_tsgl(). Prototype was for af_alg_pull_tsgl() instead
af_alg.c:663: warning: Function parameter or member 'areq' not described in 'af_alg_free_areq_sgls'
af_alg.c:700: warning: Function parameter or member 'sk' not described in 'af_alg_wait_for_wmem'
af_alg.c:700: warning: Function parameter or member 'flags' not described in 'af_alg_wait_for_wmem'
af_alg.c:731: warning: Function parameter or member 'sk' not described in 'af_alg_wmem_wakeup'
af_alg.c:757: warning: Function parameter or member 'sk' not described in 'af_alg_wait_for_data'
af_alg.c:757: warning: Function parameter or member 'flags' not described in 'af_alg_wait_for_data'
af_alg.c:757: warning: Function parameter or member 'min' not described in 'af_alg_wait_for_data'
af_alg.c:796: warning: Function parameter or member 'sk' not described in 'af_alg_data_wakeup'
af_alg.c:832: warning: Function parameter or member 'sock' not described in 'af_alg_sendmsg'
af_alg.c:832: warning: Function parameter or member 'msg' not described in 'af_alg_sendmsg'
af_alg.c:832: warning: Function parameter or member 'size' not described in 'af_alg_sendmsg'
af_alg.c:832: warning: Function parameter or member 'ivsize' not described in 'af_alg_sendmsg'
af_alg.c:985: warning: Function parameter or member 'sock' not described in 'af_alg_sendpage'
af_alg.c:985: warning: Function parameter or member 'page' not described in 'af_alg_sendpage'
af_alg.c:985: warning: Function parameter or member 'offset' not described in 'af_alg_sendpage'
af_alg.c:985: warning: Function parameter or member 'size' not described in 'af_alg_sendpage'
af_alg.c:985: warning: Function parameter or member 'flags' not described in 'af_alg_sendpage'
af_alg.c:1040: warning: Function parameter or member 'areq' not described in 'af_alg_free_resources'
af_alg.c:1059: warning: Function parameter or member '_req' not described in 'af_alg_async_cb'
af_alg.c:1059: warning: Function parameter or member 'err' not described in 'af_alg_async_cb'
af_alg.c:1083: warning: Function parameter or member 'file' not described in 'af_alg_poll'
af_alg.c:1083: warning: Function parameter or member 'sock' not described in 'af_alg_poll'
af_alg.c:1083: warning: Function parameter or member 'wait' not described in 'af_alg_poll'
af_alg.c:1114: warning: Function parameter or member 'sk' not described in 'af_alg_alloc_areq'
af_alg.c:1114: warning: Function parameter or member 'areqlen' not described in 'af_alg_alloc_areq'
af_alg.c:1146: warning: Function parameter or member 'sk' not described in 'af_alg_get_rsgl'
af_alg.c:1146: warning: Function parameter or member 'msg' not described in 'af_alg_get_rsgl'
af_alg.c:1146: warning: Function parameter or member 'flags' not described in 'af_alg_get_rsgl'
af_alg.c:1146: warning: Function parameter or member 'areq' not described in 'af_alg_get_rsgl'
af_alg.c:1146: warning: Function parameter or member 'maxsize' not described in 'af_alg_get_rsgl'
af_alg.c:1146: warning: Function parameter or member 'outlen' not described in 'af_alg_get_rsgl'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-crypto@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20260413155819.042779211@linuxfoundation.org Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Josh Law <joshlaw48@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Zen1's hardware divider can leave, under certain circumstances, partial
results from previous operations. Those results can be leaked by
another, attacker thread.
When the core of io_uring was updated to handle completions
consistently and with fixed return codes, the POLL_REMOVE opcode
with updates got slightly broken. If a POLL_ADD is pending and
then POLL_REMOVE is used to update the events of that request, if that
update causes the POLL_ADD to now trigger, then that completion is lost
and a CQE is never posted.
Additionally, ensure that if an update does cause an existing POLL_ADD
to complete, that the completion value isn't always overwritten with
-ECANCELED. For that case, whatever io_poll_add() set the value to
should just be retained.
The original commit attempted to enable ACS in pci_dma_configure() prior
to IOMMU group assignment in iommu_init_device() to fix the ACS enablement
issue for OF platforms. But that assumption doesn't hold true for kernel
versions prior to v6.15, because on these older kernels,
pci_dma_configure() is called *after* iommu_init_device(). So the IOMMU
groups are already created before the ACS gets enabled. This causes the
devices that should have been split into separate groups by ACS, getting
merged into one group, thereby breaking the IOMMU isolation as reported on
the AMD machines.
So revert the offending commit to restore the IOMMU group assignment on
those affected machines. It should be noted that ACS has never really
worked on kernel versions prior to v6.15, so the revert doesn't make any
difference for OF platforms.
Reported-by: John Hancock <john@kernel.doghat.io> Reported-by: bjorn.forsman@gmail.com Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221234 Fixes: b20b659c2c6a ("PCI: Enable ACS after configuring IOMMU for OF platforms") Cc: Linux kernel regressions list <regressions@lists.linux.dev> Link: https://lore.kernel.org/regressions/2c30f181-ffc6-4d63-a64e-763cf4528f48@leemhuis.info Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 'parent' returned by fwnode_graph_get_port_parent()
with refcount incremented when 'prev' is not NULL, it
needs be put when finish using it.
Because the parent is const, introduce a new variable to
store the returned fwnode, then put it before returning
from fwnode_graph_get_next_endpoint().
Fixes: b5b41ab6b0c1 ("device property: Check fwnode->secondary in fwnode_graph_get_next_endpoint()") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-and-tested-by: Daniel Scally <djrscally@gmail.com> Link: https://lore.kernel.org/r/20221123022542.2999510-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The s390 syscall number is directly controlled by userspace, but does
not have an array_index_nospec() boundary to prevent access past the
syscall function pointer tables.
Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Fixes: 56e62a737028 ("s390: convert to generic entry") Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/2026032404-sterling-swoosh-43e6@gregkh Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
[ gor: 5.10 backport. In 5.10, commit 56e62a737028 ("s390: convert to
generic entry") has not been applied — syscall dispatch is in
assembly (entry.S), not in C (syscall.c). The equivalent to
array_index_nospec() is implemented using the same clgr/slbgr/ngr.
SVC 0 path: the user-controlled syscall number in r1 is clamped via
a single unsigned compare (clgr) followed by slbgr/ngr. The original
cghi/jnl bounds check branch is replaced — the clamp handles both
cases: in-bounds values pass through, out-of-bounds values are zeroed
(producing the same r8=0 dispatch to table[0] as the original branch).
SVC 1-255 path: syscall number from the 8-bit instruction immediate
is always in bounds. ] Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When OGM aggregation state is toggled at runtime, an existing forwarded
packet may have been allocated with only packet_len bytes, while a later
packet can still be selected for aggregation. Appending in this case can
hit skb_put overflow conditions.
Reject aggregation when the target skb tailroom cannot accommodate the new
packet. The caller then falls back to creating a new forward packet
instead of appending.
Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Cc: stable@vger.kernel.org Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Signed-off-by: Yuan Tan <tanyuan98@outlook.com> Signed-off-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Ao Zhou <n05ec@lzu.edu.cn> Signed-off-by: Yang Yang <n05ec@lzu.edu.cn> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
[ Adjust context ] Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When device_get_child_node_count() got split to the fwnode and device
respective APIs, the fwnode didn't inherit the ability to traverse over
the secondary fwnode. Hence any user, that switches from device to fwnode
API misses this feature. In particular, this was revealed by the commit 1490cbb9dbfd ("device property: Split fwnode_get_child_node_count()")
that effectively broke the GPIO enumeration on Intel Galileo boards.
Fix this by moving the secondary lookup from device to fwnode API.
Note, in general no device_*() API should go into the depth of the fwnode
implementation.
Fixes: 114dbb4fa7c4 ("drivers property: When no children in primary, try secondary") Cc: stable@vger.kernel.org Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com> Link: https://patch.msgid.link/20260210135822.47335-1-andriy.shevchenko@linux.intel.com Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some of the fwnode APIs might return an error pointer instead of NULL
or valid fwnode handle. The result of such API call may be considered
optional and hence the test for it is usually done in a form of
fwnode = fwnode_find_reference(...);
if (IS_ERR(fwnode))
...error handling...
Nevertheless the resulting fwnode may have bumped the reference count
and hence caller of the above API is obliged to call fwnode_handle_put().
Since fwnode may be not valid either as NULL or error pointer the check
has to be performed there. This approach uglifies the code and adds
a point of making a mistake, i.e. forgetting about error point case.
To prevent this, allow an error pointer to be passed to the fwnode APIs.
Fixes: 83b34afb6b79 ("device property: Introduce fwnode_find_reference()") Reported-by: Nuno Sá <nuno.sa@analog.com> Tested-by: Nuno Sá <nuno.sa@analog.com> Acked-by: Nuno Sá <nuno.sa@analog.com> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 2692c614f8f0 ("device property: Allow secondary lookup in fwnode_get_next_child_node()") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fwnode_property_get_reference_args() searches for named properties
against a fwnode_handle, but these could instead be against the fwnode's
secondary. If the property isn't found against the primary, check the
secondary to see if it's there instead.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Daniel Scally <djrscally@gmail.com> Link: https://lore.kernel.org/r/20211128232455.39332-1-djrscally@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 2692c614f8f0 ("device property: Allow secondary lookup in fwnode_get_next_child_node()") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sensor drivers often check for an endpoint to make sure that they're
connected to a consuming device like a CIO2 during .probe(). Some of
those endpoints might be in the form of software_nodes assigned as
a secondary to the device's fwnode_handle. Account for this possibility
in fwnode_graph_get_next_endpoint() to avoid having to do it in the
sensor drivers themselves.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Daniel Scally <djrscally@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 2692c614f8f0 ("device property: Allow secondary lookup in fwnode_get_next_child_node()") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Historically we have a few variants how we access dev->fwnode
and dev->of_node. Some of the functions during development
gained different versions of the getters. Unify access to of_node
and as a side change slightly refactor ACPI specific branches.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 2692c614f8f0 ("device property: Allow secondary lookup in fwnode_get_next_child_node()") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some types of fwnode_handle do not implement the device_is_available()
check, such as those created by software_nodes. There isn't really a
meaningful way to check for the availability of a device that doesn't
actually exist, so if the check isn't implemented just assume that the
"device" is present.
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Daniel Scally <djrscally@gmail.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Stable-dep-of: 2692c614f8f0 ("device property: Allow secondary lookup in fwnode_get_next_child_node()") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add fwnode_is_ancestor_of() helper function to check if a fwnode is an
ancestor of another fwnode.
Add fwnode_get_next_parent_dev() helper function that take as input a
fwnode and finds the closest ancestor fwnode that has a corresponding
struct device and returns that struct device.
nvme_fc_delete_assocation() waits for pending I/O to complete before
returning, and an error can cause ->ioerr_work to be queued after
cancel_work_sync() had been called. Move the call to cancel_work_sync() to
be after nvme_fc_delete_association() to ensure ->ioerr_work is not running
when the nvme_fc_ctrl object is freed. Otherwise the following can occur:
The backport of upstream commit 0a2c5495b6d1 was incorrectly applied.
The cancel_work_sync() call for ->ioerr_work was added to
nvme_fc_reset_ctrl_work() instead of nvme_fc_delete_ctrl().
Revert this commit so the correct fix can be applied.
Currently the code attempts to accept requests regardless of the
command identifier which may cause multiple requests to be marked
as pending (FLAG_DEFER_SETUP) which can cause more than
L2CAP_ECRED_MAX_CID(5) to be allocated in l2cap_ecred_rsp_defer
causing an overflow.
The spec is quite clear that the same identifier shall not be used on
subsequent requests:
'Within each signaling channel a different Identifier shall be used
for each successive request or indication.'
https://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d
So this attempts to check if there are any channels pending with the
same identifier and rejects if any are found.
Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Reported-by: Yiming Qian <yimingqian591@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
[ adapted variable names ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ext4_inode_attach_jinode() publishes ei->jinode to concurrent users.
It used to set ei->jinode before jbd2_journal_init_jbd_inode(),
allowing a reader to observe a non-NULL jinode with i_vfs_inode
still unset.
The fast commit flush path can then pass this jinode to
jbd2_wait_inode_data(), which dereferences i_vfs_inode->i_mapping and
may crash.
Fix this by initializing the jbd2_inode first.
Use smp_wmb() and WRITE_ONCE() to publish ei->jinode after
initialization. Readers use READ_ONCE() to fetch the pointer.
Fixes: a361293f5fede ("jbd2: Fix oops in jbd2_journal_file_inode()") Cc: stable@vger.kernel.org Signed-off-by: Li Chen <me@linux.beauty> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20260225082617.147957-1-me@linux.beauty Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
[ adapted READ_ONCE(jinode) wrapping to split ext4_fc_submit_inode_data_all() and ext4_fc_wait_inode_data_all() ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During code review, Joseph found that ext4_fc_replay_inode() calls
ext4_get_fc_inode_loc() to get the inode location, which holds a
reference to iloc.bh that must be released via brelse().
However, several error paths jump to the 'out' label without
releasing iloc.bh:
The unmount sequence in xfs_unmount_flush_inodes() pushed the AIL while
background reclaim and inodegc are still running. This is broken
independently of any use-after-free issues - background reclaim and
inodegc should not be running while the AIL is being pushed during
unmount, as inodegc can dirty and insert inodes into the AIL during the
flush, and background reclaim can race to abort and free dirty inodes.
Reorder xfs_unmount_flush_inodes() to stop inodegc and cancel background
reclaim before pushing the AIL. Stop inodegc before cancelling
m_reclaim_work because the inodegc worker can re-queue m_reclaim_work
via xfs_inodegc_set_reclaimable.
Reported-by: syzbot+652af2b3c5569c4ab63c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=652af2b3c5569c4ab63c Fixes: 90c60e164012 ("xfs: xfs_iflush() is no longer necessary") Cc: stable@vger.kernel.org # v5.9 Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
[ dropped xfs_inodegc_stop() call ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In xfs_inode_item_push() and xfs_qm_dquot_logitem_push(), the AIL lock
is dropped to perform buffer IO. Once the cluster buffer no longer
protects the log item from reclaim, the log item may be freed by
background reclaim or the dquot shrinker. The subsequent spin_lock()
call dereferences lip->li_ailp, which is a use-after-free.
Fix this by saving the ailp pointer in a local variable while the AIL
lock is held and the log item is guaranteed to be valid.
Reported-by: syzbot+652af2b3c5569c4ab63c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=652af2b3c5569c4ab63c Fixes: 90c60e164012 ("xfs: xfs_iflush() is no longer necessary") Cc: stable@vger.kernel.org # v5.9 Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Yuto Ohnuki <ytohnuki@amazon.com> Signed-off-by: Carlos Maiolino <cem@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The above scenarios occur in initialization failures and teardown
paths, there are no parallel operations on the resources released
by kvfree(), this commit therefore remove rcu_read_lock/unlock() and
use rcu_access_pointer() instead of rcu_dereference() operations.
On arm64 server, we found folio that get from migration entry isn't locked
in softleaf_to_folio(). This issue triggers when mTHP splitting and
zap_nonpresent_ptes() races, and the root cause is lack of memory barrier
in softleaf_to_folio(). The race is as follows:
CPU0 CPU1
deferred_split_scan() zap_nonpresent_ptes()
lock folio
split_folio()
unmap_folio()
change ptes to migration entries
__split_folio_to_order() softleaf_to_folio()
set flags(including PG_locked) for tail pages folio = pfn_folio(softleaf_to_pfn(entry))
smp_wmb() VM_WARN_ON_ONCE(!folio_test_locked(folio))
prep_compound_page() for tail pages
In __split_folio_to_order(), smp_wmb() guarantees page flags of tail pages
are visible before the tail page becomes non-compound. smp_wmb() should
be paired with smp_rmb() in softleaf_to_folio(), which is missed. As a
result, if zap_nonpresent_ptes() accesses migration entry that stores tail
pfn, softleaf_to_folio() may see the updated compound_head of tail page
before page->flags.
This issue will trigger VM_WARN_ON_ONCE() in pfn_swap_entry_folio()
because of the race between folio split and zap_nonpresent_ptes()
leading to a folio incorrectly undergoing modification without a folio
lock being held.
This is a BUG_ON() before commit 93976a20345b ("mm: eliminate further
swapops predicates"), which in merged in v6.19-rc1.
To fix it, add missing smp_rmb() if the softleaf entry is migration entry
in softleaf_to_folio() and softleaf_to_page().
[tujinjiang@huawei.com: update function name and comments] Link: https://lkml.kernel.org/r/20260321075214.3305564-1-tujinjiang@huawei.com Link: https://lkml.kernel.org/r/20260319012541.4158561-1-tujinjiang@huawei.com Fixes: e9b61f19858a ("thp: reintroduce split_huge_page()") Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Barry Song <baohua@kernel.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ adapted upstream leafops.h changes to swapops.h ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit b81ac4395bbe ("usb: gadget: uvc: allow for application to cleanly
shutdown") introduced two stages of synchronization waits totaling 1500ms
in uvc_function_unbind() to prevent several types of kernel panics.
However, this timing-based approach is insufficient during power
management (PM) transitions.
When the PM subsystem starts freezing user space processes, the
wait_event_interruptible_timeout() is aborted early, which allows the
unbind thread to proceed and nullify the gadget pointer
(cdev->gadget = NULL):
[ 814.123447][ T947] configfs-gadget.g1 gadget.0: uvc: uvc_function_unbind()
[ 814.178583][ T3173] PM: suspend entry (deep)
[ 814.192487][ T3173] Freezing user space processes
[ 814.197668][ T947] configfs-gadget.g1 gadget.0: uvc: uvc_function_unbind no clean disconnect, wait for release
When the PM subsystem resumes or aborts the suspend and tasks are
restarted, the V4L2 release path is executed and attempts to access the
already nullified gadget pointer, triggering a kernel panic:
Address the race condition and NULL pointer dereference by:
1. State Synchronization (flag + mutex)
Introduce a 'func_unbound' flag in struct uvc_device. This allows
uvc_function_disconnect() to safely skip accessing the nullified
cdev->gadget pointer. As suggested by Alan Stern, this flag is protected
by a new mutex (uvc->lock) to ensure proper memory ordering and prevent
instruction reordering or speculative loads. This mutex is also used to
protect 'func_connected' for consistent state management.
2. Explicit Synchronization (completion)
Use a completion to synchronize uvc_function_unbind() with the
uvc_vdev_release() callback. This prevents Use-After-Free (UAF) by
ensuring struct uvc_device is freed after all video device resources
are released.
Fixes: b81ac4395bbe ("usb: gadget: uvc: allow for application to cleanly shutdown") Cc: stable <stable@kernel.org> Suggested-by: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jimmy Hu <hhhuuu@google.com> Link: https://patch.msgid.link/20260320065427.1374555-1-hhhuuu@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ replaced guard()/scoped_guard() macros ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A race condition between gether_disconnect() and eth_stop() leads to a
NULL pointer dereference. Specifically, if eth_stop() is triggered
concurrently while gether_disconnect() is tearing down the endpoints,
eth_stop() attempts to access the cleared endpoint descriptor, causing
the following NPE:
Because eth_stop() crashes while holding the dev->lock, the thread
running gether_disconnect() fails to acquire the same lock and spins
forever, resulting in a hardlockup:
Core - Debugging Information for Hardlockup core(7)
Call trace:
queued_spin_lock_slowpath+0x94/0x488
_raw_spin_lock+0x64/0x6c
gether_disconnect+0x19c/0x1e8
ncm_set_alt+0x68/0x1a0
composite_setup+0x6a0/0xc50
The root cause is that the clearing of dev->port_usb in
gether_disconnect() is delayed until the end of the function.
Move the clearing of dev->port_usb to the very beginning of
gether_disconnect() while holding dev->lock. This cuts off the link
immediately, ensuring eth_stop() will see dev->port_usb as NULL and
safely bail out.
There was an issue when you did the following:
- setup and bind an hid gadget
- open /dev/hidg0
- use the resulting fd in EPOLL_CTL_ADD
- unbind the UDC
- bind the UDC
- use the fd in EPOLL_CTL_DEL
When CONFIG_DEBUG_LIST was enabled, a list_del corruption was reported
within remove_wait_queue (via ep_remove_wait_queue). After some
debugging I found out that the queues, which f_hid registers via
poll_wait were the problem. These were initialized using
init_waitqueue_head inside hidg_bind. So effectively, the bind function
re-initialized the queues while there were still items in them.
The solution is to move the initialization from hidg_bind to hidg_alloc
to extend their lifetimes to the lifetime of the function instance.
Additionally, I found many other possibly problematic init calls in the
bind function, which I moved as well.
Userspace can create an unlimited number of rfkill events if the system
is so configured, while not consuming them from the rfkill file
descriptor, causing a potential out of memory situation. Prevent this
from bounding the number of pending rfkill events at a "large" number
(i.e. 1000) to prevent abuses like this.
Cc: Johannes Berg <johannes@sipsolutions.net> 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> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/2026033013-disfigure-scroll-e25e@gregkh Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[ replaced `rfkill_event_ext` with `rfkill_event`, `scoped_guard` with explicit mutex calls, and removed outer `data->mtx` lock in `rfkill_fop_open` to avoid deadlock with new internal locking ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The seg6 lwtunnel uses a single dst_cache per encap route, shared
between seg6_input_core() and seg6_output_core(). These two paths
can perform the post-encap SID lookup in different routing contexts
(e.g., ip rules matching on the ingress interface, or VRF table
separation). Whichever path runs first populates the cache, and the
other reuses it blindly, bypassing its own lookup.
Fix this by splitting the cache into cache_input and cache_output,
so each path maintains its own cached dst independently.
Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels") Cc: stable@vger.kernel.org Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Justin Iurman <justin.iurman@gmail.com> Link: https://patch.msgid.link/20260404004405.4057-2-andrea.mayer@uniroma2.it Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ adapted cache field references ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When kobject_init_and_add() fails, cpufreq_dbs_governor_init() calls
kobject_put(&dbs_data->attr_set.kobj).
The kobject release callback cpufreq_dbs_data_release() calls
gov->exit(dbs_data) and kfree(dbs_data), but the current error path
then calls gov->exit(dbs_data) and kfree(dbs_data) again, causing a
double free.
Keep the direct kfree(dbs_data) for the gov->init() failure path, but
after kobject_init_and_add() has been called, let kobject_put() handle
the cleanup through cpufreq_dbs_data_release().
Fixes: 4ebe36c94aed ("cpufreq: Fix kobject memleak") Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com> Reviewed-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: All applicable <stable@vger.kernel.org> Link: https://patch.msgid.link/20260401024535.1395801-1-lgs201920130244@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Due to the kobject embedded in the dbs_data doest not has a release()
method yet, it needs to use kfree() to free dbs_data directly when
governor fails to allocate the tunner field of dbs_data.
Commit 3ed2b549b39f ("ALSA: pcm: fix wait_time calculations") corrected
the PCM wait_time calculations and in doing so reduced the calculated
wait_time. This exposed an issue with the Tegra Master Volume Control
(MVC) device where the reduced wait_time caused the MVC to fail. For now
fix this by setting the default wait_time for Tegra to be 500ms.
Fixes: 3ed2b549b39f ("ALSA: pcm: fix wait_time calculations") Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Link: https://lore.kernel.org/r/20230613093453.13927-1-jonathanh@nvidia.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 453b8fb68f36 ("xen/privcmd: restrict usage in
unprivileged domU") added a xenstore notifier to defer setting the
restriction target until Xenstore is ready.
XEN_PRIVCMD can be built as a module, but privcmd_exit() leaves that
notifier behind. Balance the notifier lifecycle by unregistering it on
module exit.
This is harmless even if xenstore was already ready at registration
time and the notifier was never queued on the chain.
An AF_RXRPC socket can be both client and server at the same time. When
sending new calls (ie. it's acting as a client), it uses rx->key to set the
security, and when accepting incoming calls (ie. it's acting as a server),
it uses rx->securities.
setsockopt(RXRPC_SECURITY_KEY) sets rx->key to point to an rxrpc-type key
and setsockopt(RXRPC_SECURITY_KEYRING) sets rx->securities to point to a
keyring of rxrpc_s-type keys.
Now, it should be possible to use both rx->key and rx->securities on the
same socket - but for userspace AF_RXRPC sockets rxrpc_setsockopt()
prevents that.
Fix this by:
(1) Remove the incorrect check rxrpc_setsockopt(RXRPC_SECURITY_KEYRING)
makes on rx->key.
(2) Move the check that rxrpc_setsockopt(RXRPC_SECURITY_KEY) makes on
rx->key down into rxrpc_request_key().
(3) Remove rxrpc_request_key()'s check on rx->securities.
This (in combination with a previous patch) pushes the checks down into the
functions that set those pointers and removes the cross-checks that prevent
both key and keyring being set.
Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Closes: https://sashiko.dev/#/patchset/20260401105614.1696001-10-dhowells@redhat.com Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Anderson Nascimento <anderson@allelesecurity.com>
cc: Luxiao Xu <rakukuip@gmail.com>
cc: Yuan Tan <yuantan098@gmail.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org Link: https://patch.msgid.link/20260408121252.2249051-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The jumbo_frm() chain-mode implementation unconditionally computes
len = nopaged_len - bmax;
where nopaged_len = skb_headlen(skb) (linear bytes only) and bmax is
BUF_SIZE_8KiB or BUF_SIZE_2KiB. However, the caller stmmac_xmit()
decides to invoke jumbo_frm() based on skb->len (total length including
page fragments):
When a packet has a small linear portion (nopaged_len <= bmax) but a
large total length due to page fragments (skb->len > bmax), the
subtraction wraps as an unsigned integer, producing a huge len value
(~0xFFFFxxxx). This causes the while (len != 0) loop to execute
hundreds of thousands of iterations, passing skb->data + bmax * i
pointers far beyond the skb buffer to dma_map_single(). On IOMMU-less
SoCs (the typical deployment for stmmac), this maps arbitrary kernel
memory to the DMA engine, constituting a kernel memory disclosure and
potential memory corruption from hardware.
Fix this by introducing a buf_len local variable clamped to
min(nopaged_len, bmax). Computing len = nopaged_len - buf_len is then
always safe: it is zero when the linear portion fits within a single
descriptor, causing the while (len != 0) loop to be skipped naturally,
and the fragment loop in stmmac_xmit() handles page fragments afterward.
qca_tty_receive() consumes each input byte before checking whether a
completed frame needs a fresh receive skb. When the current byte completes
a frame, the driver delivers that frame and then allocates a new skb for
the next one.
If that allocation fails, the current code returns i even though data[i]
has already been consumed and may already have completed the delivered
frame. Since serdev interprets the return value as the number of accepted
bytes, this under-reports progress by one byte and can replay the final
byte of the completed frame into a fresh parser state on the next call.
Return i + 1 in that failure path so the accepted-byte count matches the
actual receive-state progress.
Make sure to deregister the controller before dropping the reference to
the driver data on disconnect to avoid NULL-pointer dereferences or
use-after-free.
When dma_map_single() fails in tse_start_xmit(), the function returns
NETDEV_TX_OK without freeing the skb. Since NETDEV_TX_OK tells the
stack the packet was consumed, the skb is never freed, leaking memory
on every DMA mapping failure.
Add dev_kfree_skb_any() before returning to properly free the skb.
Fixes: bbd2190ce96d ("Altera TSE: Add main and header file for Altera Ethernet Driver") Cc: stable@vger.kernel.org Signed-off-by: David Carlier <devnexen@gmail.com> Link: https://patch.msgid.link/20260401211218.279185-1-devnexen@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
batadv_tt_prepare_tvlv_global_data() builds the allocation length for a
global TT response in 16-bit temporaries. When a remote originator
advertises a large enough global TT, the TT payload length plus the VLAN
header offset can exceed 65535 and wrap before kmalloc().
The full-table response path still uses the original TT payload length when
it fills tt_change, so the wrapped allocation is too small and
batadv_tt_prepare_tvlv_global_data() writes past the end of the heap object
before the later packet-size check runs.
Fix this by rejecting TT responses whose TVLV value length cannot fit in
the 16-bit TVLV payload length field.
Fixes: 7ea7b4a14275 ("batman-adv: make the TT CRC logic VLAN specific") Cc: stable@vger.kernel.org Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Co-developed-by: Yuan Tan <yuantan098@gmail.com> Signed-off-by: Yuan Tan <yuantan098@gmail.com> Suggested-by: Xin Liu <bird@lzu.edu.cn> Tested-by: Ren Wei <enjou1224z@gmail.com> Signed-off-by: Ruide Cao <caoruide123@gmail.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pn532_receive_buf() reports the number of accepted bytes to the serdev
core. The current code consumes bytes into recv_skb and may already hand
a complete frame to pn533_recv_frame() before allocating a fresh receive
buffer.
If that alloc_skb() fails, the callback returns 0 even though it has
already consumed bytes, and it leaves recv_skb as NULL for the next
receive callback. That breaks the receive_buf() accounting contract and
can also lead to a NULL dereference on the next skb_put_u8().
Allocate the receive skb lazily before consuming the next byte instead.
If allocation fails, return the number of bytes already accepted.
Reboot starts failing on Poplar since commit 8424ecdde7df ("arm64: mm:
Set ZONE_DMA size based on devicetree's dma-ranges"), which effectively
changes zone_dma_bits from 30 to 32 for arm64 platforms that do not
properly define dma-ranges in device tree. It's unclear how Poplar reboot
gets broken by this change exactly, but a dma-ranges limiting zone_dma to
the first 1 GB fixes the regression.
The PCIe reset GPIO on Poplar is actually active low. The active high
worked before because kernel driver didn't respect the setting from DT.
This is changed since commit 1d26a55fbeb9 ("PCI: histb: Switch to using
gpiod API"), and thus PCIe on Poplar got brken since then.
The GRP_ACK_MSG handler in tipc_group_proto_rcv() currently decrements
bc_ackers on every inbound group ACK, even when the same member has
already acknowledged the current broadcast round.
Because bc_ackers is a u16, a duplicate ACK received after the last
legitimate ACK wraps the counter to 65535. Once wrapped,
tipc_group_bc_cong() keeps reporting congestion and later group
broadcasts on the affected socket stay blocked until the group is
recreated.
Fix this by ignoring duplicate or stale ACKs before touching bc_acked or
bc_ackers. This makes repeated GRP_ACK_MSG handling idempotent and
prevents the underflow path.
Fixes: 2f487712b893 ("tipc: guarantee that group broadcast doesn't bypass group unicast") Cc: stable@vger.kernel.org Signed-off-by: Oleh Konko <security@1seal.org> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/41a4833f368641218e444fdcff822039.security@1seal.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nft_ct_timeout_obj_destroy() frees the timeout object with kfree()
immediately after nf_ct_untimeout(), without waiting for an RCU grace
period. Concurrent packet processing on other CPUs may still hold
RCU-protected references to the timeout object obtained via
rcu_dereference() in nf_ct_timeout_data().
Add an rcu_head to struct nf_ct_timeout and use kfree_rcu() to defer
freeing until after an RCU grace period, matching the approach already
used in nfnetlink_cttimeout.c.
KASAN report:
BUG: KASAN: slab-use-after-free in nf_conntrack_tcp_packet+0x1381/0x29d0
Read of size 4 at addr ffff8881035fe19c by task exploit/80
Backport for conflicts introdued by
- conversion from sha1 to sha256 introduced in e44a4dc4b36c ("apparmor: switch SECURITY_APPARMOR_HASH from sha1 to sha256
")
- adding of conditioanl that nests the conflicting code inside an if
condition d61c57fde819 ("apparmor: make export of raw binary profile to userspace optional")
AppArmor was putting the reference to i_private data on its end after
removing the original entry from the file system. However the inode
can and does live beyond that point and it is possible that some of
the fs call back functions will be invoked after the reference has
been put, which results in a race between freeing the data and
accessing it through the fs.
While the rawdata/loaddata is the most likely candidate to fail the
race, as it has the fewest references. If properly crafted it might be
possible to trigger a race for the other types stored in i_private.
Fix this by moving the put of i_private referenced data to the correct
place which is during inode eviction.
Backport for conflicts introdued by d61c57fde819 ("apparmor: make export of raw binary profile to userspace optional")
which nests the conflicting code inside an if condition
There is a race condition that leads to a use-after-free situation:
because the rawdata inodes are not refcounted, an attacker can start
open()ing one of the rawdata files, and at the same time remove the
last reference to this rawdata (by removing the corresponding profile,
for example), which frees its struct aa_loaddata; as a result, when
seq_rawdata_open() is reached, i_private is a dangling pointer and
freed memory is accessed.
The rawdata inodes weren't refcounted to avoid a circular refcount and
were supposed to be held by the profile rawdata reference. However
during profile removal there is a window where the vfs and profile
destruction race, resulting in the use after free.
Fix this by moving to a double refcount scheme. Where the profile
refcount on rawdata is used to break the circular dependency. Allowing
for freeing of the rawdata once all inode references to the rawdata
are put.
Differential encoding allows loops to be created if it is abused. To
prevent this the unpack should verify that a diff-encode chain
terminates.
Unfortunately the differential encode verification had two bugs.
1. it conflated states that had gone through check and already been
marked, with states that were currently being checked and marked.
This means that loops in the current chain being verified are treated
as a chain that has already been verified.
2. the order bailout on already checked states compared current chain
check iterators j,k instead of using the outer loop iterator i.
Meaning a step backwards in states in the current chain verification
was being mistaken for moving to an already verified state.
Move to a double mark scheme where already verified states get a
different mark, than the current chain being kept. This enables us
to also drop the backwards verification check that was the cause of
the second error as any already verified state is already marked.
Fixes: 031dcc8f4e84 ("apparmor: dfa add support for state differential encoding") Reported-by: Qualys Security Advisory <qsa@qualys.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com> Reviewed-by: Cengiz Can <cengiz.can@canonical.com> Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Backport for api changes introduced in
- 90c436a64a6e ("apparmor: pass cred through to audit info.")
- 92de220a7f33 ("apparmor: update policy capable checks to use a label")
An unprivileged local user can load, replace, and remove profiles by
opening the apparmorfs interfaces, via a confused deputy attack, by
passing the opened fd to a privileged process, and getting the
privileged process to write to the interface.
This does require a privileged target that can be manipulated to do
the write for the unprivileged process, but once such access is
achieved full policy management is possible and all the possible
implications that implies: removing confinement, DoS of system or
target applications by denying all execution, by-passing the
unprivileged user namespace restriction, to exploiting kernel bugs for
a local privilege escalation.
The policy management interface can not have its permissions simply
changed from 0666 to 0600 because non-root processes need to be able
to load policy to different policy namespaces.
Instead ensure the task writing the interface has privileges that
are a subset of the task that opened the interface. This is already
done via policy for confined processes, but unconfined can delegate
access to the opened fd, by-passing the usual policy check.
The verify_dfa() function only checks DEFAULT_TABLE bounds when the state
is not differentially encoded.
When the verification loop traverses the differential encoding chain,
it reads k = DEFAULT_TABLE[j] and uses k as an array index without
validation. A malformed DFA with DEFAULT_TABLE[j] >= state_count,
therefore, causes both out-of-bounds reads and writes.
[ 57.179855] ==================================================================
[ 57.180549] BUG: KASAN: slab-out-of-bounds in verify_dfa+0x59a/0x660
[ 57.180904] Read of size 4 at addr ffff888100eadec4 by task su/993
The match_char() macro evaluates its character parameter multiple
times when traversing differential encoding chains. When invoked
with *str++, the string pointer advances on each iteration of the
inner do-while loop, causing the DFA to check different characters
at each iteration and therefore skip input characters.
This results in out-of-bounds reads when the pointer advances past
the input buffer boundary.
[ 94.984676] ==================================================================
[ 94.985301] BUG: KASAN: slab-out-of-bounds in aa_dfa_match+0x5ae/0x760
[ 94.985655] Read of size 1 at addr ffff888100342000 by task file/976
Currently the number of policy namespaces is not bounded relying on
the user namespace limit. However policy namespaces aren't strictly
tied to user namespaces and it is possible to create them and nest
them arbitrarily deep which can be used to exhaust system resource.
Hard cap policy namespaces to the same depth as user namespaces.
Fixes: c88d4c7b049e8 ("AppArmor: core policy routines") Reported-by: Qualys Security Advisory <qsa@qualys.com> Reviewed-by: Ryan Lee <ryan.lee@canonical.com> Reviewed-by: Cengiz Can <cengiz.can@canonical.com> Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The profile removal code uses recursion when removing nested profiles,
which can lead to kernel stack exhaustion and system crashes.
Reproducer:
$ pf='a'; for ((i=0; i<1024; i++)); do
echo -e "profile $pf { \n }" | apparmor_parser -K -a;
pf="$pf//x";
done
$ echo -n a > /sys/kernel/security/apparmor/.remove
Replace the recursive __aa_profile_list_release() approach with an
iterative approach in __remove_profile(). The function repeatedly
finds and removes leaf profiles until the entire subtree is removed,
maintaining the same removal semantic without recursion.
The function sets `*ns = NULL` on every call, leaking the namespace
string allocated in previous iterations when multiple profiles are
unpacked. This also breaks namespace consistency checking since *ns
is always NULL when the comparison is made.
Remove the incorrect assignment.
The caller (aa_unpack) initializes *ns to NULL once before the loop,
which is sufficient.
Fixes: dd51c8485763 ("apparmor: provide base for multiple profiles to be replaced at once") Reported-by: Qualys Security Advisory <qsa@qualys.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com> Reviewed-by: Cengiz Can <cengiz.can@canonical.com> Signed-off-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com> Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Backport for conflicts caused by ad596ea74e74 ("apparmor: group dfa policydb unpacking")
- rearrange and consolidated the unpack.
b11e51dd7094 ("apparmor: test: make static symbols visible during kunit testing")
- rename function and make it visible to kunit tests
Start states are read from untrusted data and used as indexes into the
DFA state tables. The aa_dfa_next() function call in unpack_pdb() will
access dfa->tables[YYTD_ID_BASE][start], and if the start state exceeds
the number of states in the DFA, this results in an out-of-bound read.
==================================================================
BUG: KASAN: slab-out-of-bounds in aa_dfa_next+0x2a1/0x360
Read of size 4 at addr ffff88811956fb90 by task su/1097
...
Reject policies with out-of-bounds start states during unpacking
to prevent the issue.
As reported, ever since commit 1013af4f585f ("mm/hugetlb: fix
huge_pmd_unshare() vs GUP-fast race") we can end up in some situations
where we perform so many IPI broadcasts when unsharing hugetlb PMD page
tables that it severely regresses some workloads.
In particular, when we fork()+exit(), or when we munmap() a large
area backed by many shared PMD tables, we perform one IPI broadcast per
unshared PMD table.
There are two optimizations to be had:
(1) When we process (unshare) multiple such PMD tables, such as during
exit(), it is sufficient to send a single IPI broadcast (as long as
we respect locking rules) instead of one per PMD table.
Locking prevents that any of these PMD tables could get reused before
we drop the lock.
(2) When we are not the last sharer (> 2 users including us), there is
no need to send the IPI broadcast. The shared PMD tables cannot
become exclusive (fully unshared) before an IPI will be broadcasted
by the last sharer.
Concurrent GUP-fast could walk into a PMD table just before we
unshared it. It could then succeed in grabbing a page from the
shared page table even after munmap() etc succeeded (and supressed
an IPI). But there is not difference compared to GUP-fast just
sleeping for a while after grabbing the page and re-enabling IRQs.
Most importantly, GUP-fast will never walk into page tables that are
no-longer shared, because the last sharer will issue an IPI
broadcast.
(if ever required, checking whether the PUD changed in GUP-fast
after grabbing the page like we do in the PTE case could handle
this)
So let's rework PMD sharing TLB flushing + IPI sync to use the mmu_gather
infrastructure so we can implement these optimizations and demystify the
code at least a bit. Extend the mmu_gather infrastructure to be able to
deal with our special hugetlb PMD table sharing implementation.
To make initialization of the mmu_gather easier when working on a single
VMA (in particular, when dealing with hugetlb), provide
tlb_gather_mmu_vma().
We'll consolidate the handling for (full) unsharing of PMD tables in
tlb_unshare_pmd_ptdesc() and tlb_flush_unshared_tables(), and track
in "struct mmu_gather" whether we had (full) unsharing of PMD tables.
Because locking is very special (concurrent unsharing+reuse must be
prevented), we disallow deferring flushing to tlb_finish_mmu() and instead
require an explicit earlier call to tlb_flush_unshared_tables().
>From hugetlb code, we call huge_pmd_unshare_flush() where we make sure
that the expected lock protecting us from concurrent unsharing+reuse is
still held.
Check with a VM_WARN_ON_ONCE() in tlb_finish_mmu() that
tlb_flush_unshared_tables() was properly called earlier.
Document it all properly.
Notes about tlb_remove_table_sync_one() interaction with unsharing:
There are two fairly tricky things:
(1) tlb_remove_table_sync_one() is a NOP on architectures without
CONFIG_MMU_GATHER_RCU_TABLE_FREE.
Here, the assumption is that the previous TLB flush would send an
IPI to all relevant CPUs. Careful: some architectures like x86 only
send IPIs to all relevant CPUs when tlb->freed_tables is set.
The relevant architectures should be selecting
MMU_GATHER_RCU_TABLE_FREE, but x86 might not do that in stable
kernels and it might have been problematic before this patch.
Also, the arch flushing behavior (independent of IPIs) is different
when tlb->freed_tables is set. Do we have to enlighten them to also
take care of tlb->unshared_tables? So far we didn't care, so
hopefully we are fine. Of course, we could be setting
tlb->freed_tables as well, but that might then unnecessarily flush
too much, because the semantics of tlb->freed_tables are a bit
fuzzy.
This patch changes nothing in this regard.
(2) tlb_remove_table_sync_one() is not a NOP on architectures with
CONFIG_MMU_GATHER_RCU_TABLE_FREE that actually don't need a sync.
Take x86 as an example: in the common case (!pv, !X86_FEATURE_INVLPGB)
we still issue IPIs during TLB flushes and don't actually need the
second tlb_remove_table_sync_one().
This optimized can be implemented on top of this, by checking e.g., in
tlb_remove_table_sync_one() whether we really need IPIs. But as
described in (1), it really must honor tlb->freed_tables then to
send IPIs to all relevant CPUs.
Notes on TLB flushing changes:
(1) Flushing for non-shared PMD tables
We're converting from flush_hugetlb_tlb_range() to
tlb_remove_huge_tlb_entry(). Given that we properly initialize the
MMU gather in tlb_gather_mmu_vma() to be hugetlb aware, similar to
__unmap_hugepage_range(), that should be fine.
(2) Flushing for shared PMD tables
We're converting from various things (flush_hugetlb_tlb_range(),
tlb_flush_pmd_range(), flush_tlb_range()) to tlb_flush_pmd_range().
tlb_flush_pmd_range() achieves the same that
tlb_remove_huge_tlb_entry() would achieve in these scenarios.
Note that tlb_remove_huge_tlb_entry() also calls
__tlb_remove_tlb_entry(), however that is only implemented on
powerpc, which does not support PMD table sharing.
Similar to (1), tlb_gather_mmu_vma() should make sure that TLB
flushing keeps on working as expected.
Further, note that the ptdesc_pmd_pts_dec() in huge_pmd_share() is not a
concern, as we are holding the i_mmap_lock the whole time, preventing
concurrent unsharing. That ptdesc_pmd_pts_dec() usage will be removed
separately as a cleanup later.
There are plenty more cleanups to be had, but they have to wait until
this is fixed.
[david@kernel.org: fix kerneldoc] Link: https://lkml.kernel.org/r/f223dd74-331c-412d-93fc-69e360a5006c@kernel.org Link: https://lkml.kernel.org/r/20251223214037.580860-5-david@kernel.org Fixes: 1013af4f585f ("mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race") Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org> Reported-by: "Uschakow, Stanislav" <suschako@amazon.de> Closes: https://lore.kernel.org/all/4d3878531c76479d9f8ca9789dc6485d@amazon.de/ Tested-by: Laurence Oberman <loberman@redhat.com> Acked-by: Harry Yoo <harry.yoo@oracle.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Rik van Riel <riel@surriel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 8ce720d5bd91e9dc16db3604aa4b1bf76770a9a1)
[ David: We don't have ptdesc and the wrappers, so work directly on
page->pt_share_count and pass "struct page" instead of "struct ptdesc".
CONFIG_HUGETLB_PMD_PAGE_TABLE_SHARING is still called
CONFIG_ARCH_WANT_HUGE_PMD_SHARE and is set even without
CONFIG_HUGETLB_PAGE. We don't have 550a7d60bd5e ("mm, hugepages: add
mremap() support for hugepage backed vma"), so move_hugetlb_page_tables()
does not exist. We don't have 40549ba8f8e0 ("hugetlb: use new vma_lock
for pmd sharing synchronization") and a98a2f0c8ce1 ("mm/rmap: split
migration into its own so changes in mm/rmap.c looks quite different. We
don't have 4ddb4d91b82f ("hugetlb: do not update address
in huge_pmd_unshare"), so huge_pmd_unshare() still gets a pointer to
an address. tlb_gather_mmu() + tlb_finish_mmu() still consume ranges, so
also teach tlb_gather_mmu_vma() to forward ranges. Some smaller
contextual stuff, in particular, around tlb_gather_mmu_full(). ] Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
PMD page table unsharing no longer touches the refcount of a PMD page
table. Also, it is not about dropping the refcount of a "PMD page" but
the "PMD page table".
Let's just simplify by saying that the PMD page table was unmapped,
consequently also unmapping the folio that was mapped into this page.
This code should be deduplicated in the future.
Link: https://lkml.kernel.org/r/20251223214037.580860-4-david@kernel.org Fixes: 59d9094df3d7 ("mm: hugetlb: independent PMD page table shared count") Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Rik van Riel <riel@surriel.com> Tested-by: Laurence Oberman <loberman@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Uschakow, Stanislav" <suschako@amazon.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit a8682d500f691b6dfaa16ae1502d990aeb86e8be)
[ David: We don't have 40549ba8f8e0 ("hugetlb: use new vma_lock
for pmd sharing synchronization") and a98a2f0c8ce1 ("mm/rmap: split
migration into its own so changes in mm/rmap.c looks quite different. ] Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Ever since we stopped using the page count to detect shared PMD page
tables, these comments are outdated.
The only reason we have to flush the TLB early is because once we drop the
i_mmap_rwsem, the previously shared page table could get freed (to then
get reallocated and used for other purpose). So we really have to flush
the TLB before that could happen.
So let's simplify the comments a bit.
The "If we unshared PMDs, the TLB flush was not recorded in mmu_gather."
part introduced as in commit a4a118f2eead ("hugetlbfs: flush TLBs
correctly after huge_pmd_unshare") was confusing: sure it is recorded in
the mmu_gather, otherwise tlb_flush_mmu_tlbonly() wouldn't do anything.
So let's drop that comment while at it as well.
We'll centralize these comments in a single helper as we rework the code
next.
Link: https://lkml.kernel.org/r/20251223214037.580860-3-david@kernel.org Fixes: 59d9094df3d7 ("mm: hugetlb: independent PMD page table shared count") Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Rik van Riel <riel@surriel.com> Tested-by: Laurence Oberman <loberman@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Uschakow, Stanislav" <suschako@amazon.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 3937027caecb4f8251e82dd857ba1d749bb5a428) Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Patch series "mm/hugetlb: fixes for PMD table sharing (incl. using
mmu_gather)", v3.
One functional fix, one performance regression fix, and two related
comment fixes.
I cleaned up my prototype I recently shared [1] for the performance fix,
deferring most of the cleanups I had in the prototype to a later point.
While doing that I identified the other things.
The goal of this patch set is to be backported to stable trees "fairly"
easily. At least patch #1 and #4.
Patch #1 fixes hugetlb_pmd_shared() not detecting any sharing
Patch #2 + #3 are simple comment fixes that patch #4 interacts with.
Patch #4 is a fix for the reported performance regression due to excessive
IPI broadcasts during fork()+exit().
The last patch is all about TLB flushes, IPIs and mmu_gather.
Read: complicated
There are plenty of cleanups in the future to be had + one reasonable
optimization on x86. But that's all out of scope for this series.
Runtime tested, with a focus on fixing the performance regression using
the original reproducer [2] on x86.
This patch (of 4):
We switched from (wrongly) using the page count to an independent shared
count. Now, shared page tables have a refcount of 1 (excluding
speculative references) and instead use ptdesc->pt_share_count to identify
sharing.
We didn't convert hugetlb_pmd_shared(), so right now, we would never
detect a shared PMD table as such, because sharing/unsharing no longer
touches the refcount of a PMD table.
Page migration, like mbind() or migrate_pages() would allow for migrating
folios mapped into such shared PMD tables, even though the folios are not
exclusive. In smaps we would account them as "private" although they are
"shared", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the
pagemap interface.
Fix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared().
commit 59d9094df3d79 ("mm: hugetlb: independent PMD page table shared
count") introduced ->pt_share_count dedicated to hugetlb PMD share count
tracking, but omitted fixing copy_hugetlb_page_range(), leaving the
function relying on page_count() for tracking that no longer works.
When lazy page table copy for hugetlb is disabled, that is, revert commit bcd51a3c679d ("hugetlb: lazy page table copies in fork()") fork()'ing with
hugetlb PMD sharing quickly lockup -
There are two options to resolve the potential latent issue:
1. warn against PMD sharing in copy_hugetlb_page_range(),
2. fix it.
This patch opts for the second option.
While at it, simplify the comment, the details are not actually relevant
anymore.
Link: https://lkml.kernel.org/r/20250916004520.1604530-1-jane.chu@oracle.com Fixes: 59d9094df3d7 ("mm: hugetlb: independent PMD page table shared count") Signed-off-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Hildenbrand <david@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Liu Shixin <liushixin2@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 14967a9c7d247841b0312c48dcf8cd29e55a4cc8)
[ David: We don't have ptdesc and the wrappers, so work directly on the
page->pt_share_count. CONFIG_HUGETLB_PMD_PAGE_TABLE_SHARING is still
called CONFIG_ARCH_WANT_HUGE_PMD_SHARE. ] Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
If the pagetables are shared, we shouldn't copy or take references. Since
src could have unshared and dst shares with another vma, huge_pte_none()
is thus used to determine whether dst_pte is shared. But this check isn't
reliable. A shared pte could have pte none in pagetable in fact. The
page count of ptep page should be checked here in order to reliably
determine whether pte is shared.
[lukas.bulwahn@gmail.com: remove unused local variable dst_entry in copy_hugetlb_page_range()] Link: https://lkml.kernel.org/r/20220822082525.26071-1-lukas.bulwahn@gmail.com Link: https://lkml.kernel.org/r/20220816130553.31406-7-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 3aa4ed8040e1535d95c03cef8b52cf11bf0d8546)
[ David: We don't have 4eae4efa2c29 ("hugetlb: do early cow when page
pinned on src mm", so there are some contextual conflicts. ] Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
mm/hugetlb: fix skipping of unsharing of pmd page tables
In the 5.10 backport of commit b30c14cd6102 ("hugetlb: unshare some PMDs
when splitting VMAs") we seemed to have missed that huge_pmd_unshare()
still adjusts the address itself.
For this reason, commit 6dfeaff93be1 ("hugetlb/userfaultfd: unshare all
pmds for hugetlbfs when register wp") explicitly handled this case by
passing a temporary variable instead.
Fix it in 5.10 by doing the same thing.
Fixes: f1082f5f3d02 ("hugetlb: unshare some PMDs when splitting VMAs") Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
To avoid racing with FF playback events and corrupting device's event
queue take event_lock spinlock when calling uinput_dev_event() when
submitting a FF upload or erase "event".
A lockdep circular locking dependency warning can be triggered
reproducibly when using a force-feedback gamepad with uinput (for
example, playing ELDEN RING under Wine with a Flydigi Vader 5
controller):
The cycle is caused by four lock acquisition paths:
1. ff upload: input_ff_upload() holds ff->mutex and calls
uinput_dev_upload_effect() -> uinput_request_submit() ->
uinput_request_send(), which acquires udev->mutex.
2. device create: uinput_ioctl_handler() holds udev->mutex and calls
uinput_create_device() -> input_register_device(), which acquires
input_mutex.
3. device register: input_register_device() holds input_mutex and
calls kbd_connect() -> input_register_handle(), which acquires
dev->mutex.
4. evdev release: evdev_release() calls input_flush_device() under
dev->mutex, which calls input_ff_flush() acquiring ff->mutex.
Fix this by introducing a new state_lock spinlock to protect
udev->state and udev->dev access in uinput_request_send() instead of
acquiring udev->mutex. The function only needs to atomically check
device state and queue an input event into the ring buffer via
uinput_dev_event() -- both operations are safe under a spinlock
(ktime_get_ts64() and wake_up_interruptible() do not sleep). This
breaks the ff->mutex -> udev->mutex link since a spinlock is a leaf in
the lock ordering and cannot form cycles with mutexes.
To keep state transitions visible to uinput_request_send(), protect
writes to udev->state in uinput_create_device() and
uinput_destroy_device() with the same state_lock spinlock.
Additionally, move init_completion(&request->done) from
uinput_request_send() to uinput_request_submit() before
uinput_request_reserve_slot(). Once the slot is allocated,
uinput_flush_requests() may call complete() on it at any time from
the destroy path, so the completion must be initialised before the
request becomes visible.
struct xfrm_user_report is a __u8 proto field followed by a struct
xfrm_selector which means there is three "empty" bytes of padding, but
the padding is never zeroed before copying to userspace. Fix that up by
zeroing the structure before setting individual member variables.
Cc: stable <stable@kernel.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Simon Horman <horms@kernel.org> Assisted-by: gregkh_clanker_t1000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB drivers bind to USB interfaces and any device managed resources
should have their lifetime tied to the interface rather than parent USB
device. This avoids issues like memory leaks when drivers are unbound
without their devices being physically disconnected (e.g. on probe
deferral or configuration changes).
Fix the USB anchor lifetime so that it is released on driver unbind.
Fixes: 8b4c0009313f ("rt2x00usb: Use usb anchor to manage URB") Cc: stable@vger.kernel.org # 4.7 Cc: Vishal Thanki <vishalthanki@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Acked-by: Stanislaw Gruszka <stf_xl@wp.pl> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/20260327113219.1313748-1-johan@kernel.org Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the ChaCha permutation is invertible, the local variable
'permuted_state' is sufficient to compute the original 'state', and thus
the key, even after the permutation has been done.
While the kernel is quite inconsistent about zeroizing secrets on the
stack (and some prominent userspace crypto libraries don't bother at all
since it's not guaranteed to work anyway), the kernel does try to do it
as a best practice, especially in cases involving the RNG.
Thus, explicitly zeroize 'permuted_state' before it goes out of scope.
WARNING: CPU: 0 PID: 16 at io_uring/tctx.c:51 __io_uring_free+0xfa/0x140 io_uring/tctx.c:51
which is the
WARN_ON_ONCE(!xa_empty(&tctx->xa));
sanity check in __io_uring_free() when a io_uring_task is going through
its final put. The syzbot test case includes injecting memory allocation
failures, and it very much looks like xa_store() can fail one of its
memory allocations and end up with ->head being non-NULL even though no
entries exist in the xarray.
Until this issue gets sorted out, work around it by attempting to
iterate entries in our xarray, and WARN_ON_ONCE() if one is found.
Reported-by: syzbot+cc36d44ec9f368e443d3@syzkaller.appspotmail.com Link: https://lore.kernel.org/io-uring/673c1643.050a0220.87769.0066.GAE@google.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
[ Modify the function in io_uring.c because it's located here in v5.15. ] Signed-off-by: Robert Garcia <rob_garcia@163.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
geth_alloc() increments the reference count, but geth_free() fails to
decrement it. This prevents the configuration of attributes via configfs
after unlinking the function.
Decrement the reference count in geth_free() to ensure proper cleanup.