We have NR_syscall syscalls from [0 .. NR_syscall-1].
However the check for invalid syscall number is "> NR_syscall" as
opposed to >=. This off-by-one error erronesously allows "NR_syscall"
to be treated as valid syscall causeing out-of-bounds access into
syscall-call table ensuing a crash (holes within syscall table have a
invalid-entry handler but this is beyond the array implementing the
table).
This problem showed up on v5.6 kernel when testing glibc 2.33 (v5.10
kernel capable, includng faccessat2 syscall 439). The v5.6 kernel has
NR_syscalls=439 (0 to 438). Due to the bug, 439 passed by glibc was
not handled as -ENOSYS but processed leading to a crash.
When vzalloc() returns NULL to sha_regions, no error return code of
kexec_calculate_store_digests() is assigned. To fix this bug, ret is
assigned with -ENOMEM in this case.
Link: https://lkml.kernel.org/r/20210309083904.24321-1-baijiaju1990@gmail.com Fixes: a43cac0d9dc2 ("kexec: split kexec_file syscall code to kexec_file.c") Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reported-by: TOTE Robot <oslab@tsinghua.edu.cn> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When removing rmap_item from stable tree, STABLE_FLAG of rmap_item is
cleared with head reserved. So the following scenario might happen: For
ksm page with rmap_item1:
cmp_and_merge_page
stable_node->head = &migrate_nodes;
remove_rmap_item_from_tree, but head still equal to stable_node;
try_to_merge_with_ksm_page failed;
return;
For the same ksm page with rmap_item2, stable node migration succeed this
time. The stable_node->head does not equal to migrate_nodes now. For ksm
page with rmap_item1 again:
We would miss the rmap_item for stable_node and might result in failed
rmap_walk_ksm(). Fix this by set rmap_item->head to NULL when rmap_item
is removed from stable tree.
Link: https://lkml.kernel.org/r/20210330140228.45635-5-linmiaohe@huawei.com Fixes: 4146d2d673e8 ("ksm: make !merge_across_nodes migration safe") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
An out of bounds write happens when setting the default power state.
KASAN sees this as:
[drm] radeon: 512M of GTT memory ready.
[drm] GART: num cpu pages 131072, num gpu pages 131072
==================================================================
BUG: KASAN: slab-out-of-bounds in
radeon_atombios_parse_power_table_1_3+0x1837/0x1998 [radeon]
Write of size 4 at addr ffff88810178d858 by task systemd-udevd/157
Without KASAN, this will manifest later when the kernel attempts to
allocate memory that was stomped, since it collides with the inline slab
freelist pointer:
Normally SCTP_MIB_CURRESTAB is always incremented once asoc enter into
ESTABLISHED from the state < ESTABLISHED and decremented when the asoc
is being deleted.
However, in sctp_sf_do_dupcook_b(), the asoc's state can be changed to
ESTABLISHED from the state >= ESTABLISHED where it shouldn't increment
SCTP_MIB_CURRESTAB. Otherwise, one asoc may increment MIB_CURRESTAB
multiple times but only decrement once at the end.
I was able to reproduce it by using scapy to do the 4-way shakehands,
after that I replayed the COOKIE-ECHO chunk with 'peer_vtag' field
changed to different values, and SCTP_MIB_CURRESTAB was incremented
multiple times and never went back to 0 even when the asoc was freed.
This patch is to fix it by only incrementing SCTP_MIB_CURRESTAB when
the state < ESTABLISHED in sctp_sf_do_dupcook_b().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently the client ignores the value of the sr_eof of the SEEK
operation. According to the spec, if the server didn't find the
requested extent and reached the end of the file, the server
would return sr_eof=true. In case the request for DATA and no
data was found (ie in the middle of the hole), then the lseek
expects that ENXIO would be returned.
We (adam zabrocki, alexander matrosov, alexander tereshkin, maksym
bazalii) observed the check:
if (fh->size > sizeof(struct nfs_fh))
should not use the size of the nfs_fh struct which includes an extra two
bytes from the size field.
struct nfs_fh {
unsigned short size;
unsigned char data[NFS_MAXFHSIZE];
}
but should determine the size from data[NFS_MAXFHSIZE] so the memcpy
will not write 2 bytes beyond destination. The proposed fix is to
compare against the NFS_MAXFHSIZE directly, as is done elsewhere in fs
code base.
Fixes: d67ae825a59d ("pnfs/flexfiles: Add the FlexFile Layout Driver") Signed-off-by: Nikola Livic <nlivic@gmail.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
We need to use unsigned long subtraction and then convert to signed in
order to deal correcly with C overflow rules.
Fixes: f5062003465c ("NFS: Set an attribute barrier on all updates") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
In pci_scan_device(), if pci_setup_device() fails for any reason, the code
will not release device's of_node by calling pci_release_of_node(). Fix
that by calling the release function.
Fixes: 98d9f30c820d ("pci/of: Match PCI devices to OF nodes dynamically") Link: https://lore.kernel.org/r/20210124232826.1879-1-dmitry.baryshkov@linaro.org Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The IOMMU table is divided into pools for concurrent mappings and each
pool has a separate spinlock. When taking the ownership of an IOMMU group
to pass through a device to a VM, we lock these spinlocks which triggers
a false negative warning in lockdep (below).
This fixes it by annotating the large pool's spinlock as a nest lock
which makes lockdep not complaining when locking nested locks if
the nest lock is locked already.
===
WARNING: possible recursive locking detected
5.11.0-le_syzkaller_a+fstn1 #100 Not tainted
--------------------------------------------
qemu-system-ppc/4129 is trying to acquire lock: c0000000119bddb0 (&(p->lock)/1){....}-{2:2}, at: iommu_take_ownership+0xac/0x1e0
but task is already holding lock: c0000000119bdd30 (&(p->lock)/1){....}-{2:2}, at: iommu_take_ownership+0xac/0x1e0
other info that might help us debug this:
Possible unsafe locking scenario:
Fix the following out-of-bounds warnings by adding a new structure
wl3501_req instead of duplicating the same members in structure
wl3501_join_req and wl3501_scan_confirm:
arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [39, 108] from the object at 'sig' is out of the bounds of referenced subobject 'beacon_period' with type 'short unsigned int' at offset 36 [-Warray-bounds]
arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [25, 95] from the object at 'sig' is out of the bounds of referenced subobject 'beacon_period' with type 'short unsigned int' at offset 22 [-Warray-bounds]
The problem is that the original code is trying to copy data into a
bunch of struct members adjacent to each other in a single call to
memcpy(). Now that a new struct wl3501_req enclosing all those adjacent
members is introduced, memcpy() doesn't overrun the length of
&sig.beacon_period and &this->bss_set[i].beacon_period, because the
address of the new struct object _req_ is used as the destination,
instead.
This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().
Fix the following out-of-bounds warnings by enclosing structure members
daddr and saddr into new struct addr, in structures wl3501_md_req and
wl3501_md_ind:
arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [18, 23] from the object at 'sig' is out of the bounds of referenced subobject 'daddr' with type 'u8[6]' {aka 'unsigned char[6]'} at offset 11 [-Warray-bounds]
arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [18, 23] from the object at 'sig' is out of the bounds of referenced subobject 'daddr' with type 'u8[6]' {aka 'unsigned char[6]'} at offset 11 [-Warray-bounds]
The problem is that the original code is trying to copy data into a
couple of arrays adjacent to each other in a single call to memcpy().
Now that a new struct _addr_ enclosing those two adjacent arrays
is introduced, memcpy() doesn't overrun the length of &sig.daddr[0]
and &sig.daddr, because the address of the new struct object _addr_
is used, instead.
This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().
The ALC3263 codec on the XPS 13 9343 is also found on the Latitude 13 7350
and Venue 11 Pro 7140. They require the same handling for the combo jack to
work with a headset: GPIO pin 6 must be set.
The HDA driver always sets this pin on the ALC3263, which it distinguishes
by the codec vendor/device ID 0x10ec0288 and PCI subsystem vendor ID 0x1028
(Dell). The ASoC driver does not use PCI, so adapt this check to use DMI to
determine if Dell is the system vendor.
net/sctp/sm_make_chunk.c:3150:4: warning: 'memcpy' offset [17, 28] from the object at 'addr' is out of the bounds of referenced subobject 'v4' with type 'struct sockaddr_in' at offset 0 [-Warray-bounds]
This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().
Link: https://github.com/KSPP/linux/issues/109 Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
If the user selects the very first entry in a page and performs a
search-up operation, or selects the very last entry in a page and
performs a search-down operation that will not succeed (e.g., via
[/]asdfzzz[Up Arrow]), nconf will never terminate searching the page.
The reason is that in this case, the starting point will be set to -1
or n, which is then translated into (n - 1) (i.e., the last entry of
the page) or 0 (i.e., the first entry of the page) and finally the
search begins. This continues to work fine until the index reaches 0 or
(n - 1), at which point it will be decremented to -1 or incremented to
n, but not checked against the starting point right away. Instead, it's
wrapped around to the bottom or top again, after which the starting
point check occurs... and naturally fails.
My original implementation added another check for -1 before wrapping
the running index variable around, but Masahiro Yamada pointed out that
the actual issue is that the comparison point (starting point) exceeds
bounds (i.e., the [0,n-1] interval) in the first place and that,
instead, the starting point should be fixed.
This has the welcome side-effect of also fixing the case where the
starting point was n while searching down, which also lead to an
infinite loop.
OTOH, this code is now essentially all his work.
Amazingly, nobody seems to have been hit by this for 11 years - or at
the very least nobody bothered to debug and fix this.
selftests/bpf/Makefile includes lib.mk. With the following command
make -j60 LLVM=1 LLVM_IAS=1 <=== compile kernel
make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 V=1
some files are still compiled with gcc. This patch
fixed lib.mk issue which sets CC to gcc in all cases.
After channel switch, we should consider any beacon with a
CSA IE as a new switch. If the CSA IE is a leftover from
before the switch that the AP forgot to remove, we'll get
a CSA-to-Self.
This caused issues in iwlwifi where the firmware saw a beacon
with a CSA-to-Self with mode = 1 on the new channel after a
switch. The firmware considered this a new switch and closed
its queues. Since the beacon didn't change between before and
after the switch, we wouldn't handle it (the CRC is the same)
and we wouldn't let the firmware open its queues again or
disconnect if the CSA IE stays for too long.
Clear the CRC valid state after we switch to make sure that
we handle the beacon and handle the CSA IE as required.
syzbot is hitting "INFO: trying to register non-static key." message [1],
for "struct l2cap_chan"->tx_q.lock spinlock is not yet initialized when
l2cap_chan_del() is called due to e.g. timeout.
Since "struct l2cap_chan"->lock mutex is initialized at l2cap_chan_create()
immediately after "struct l2cap_chan" is allocated using kzalloc(), let's
as well initialize "struct l2cap_chan"->{tx_q,srej_q}.lock spinlocks there.
Currently l2cap_chan_set_defaults() reset chan->conf_state to zero.
However, there is a flag CONF_NOT_COMPLETE which is set when
creating the l2cap_chan. It is suggested that the flag should be
cleared when l2cap_chan is ready, but when l2cap_chan_set_defaults()
is called, l2cap_chan is not yet ready. Therefore, we must set this
flag as the default.
Commit eaf4fac47807 ("net: stmmac: Do not accept invalid MTU values")
started using the TX FIFO size to verify what counts as a valid MTU
request for the stmmac driver. This is unset for the ipq806x variant.
Looking at older patches for this it seems the RX + TXs buffers can be
up to 8k, so set appropriately.
(I sent this as an RFC patch in June last year, but received no replies.
I've been running with this on my hardware (a MikroTik RB3011) since
then with larger MTUs to support both the internal qca8k switch and
VLANs with no problems. Without the patch it's impossible to set the
larger MTU required to support this.)
Signed-off-by: Jonathan McDowell <noodles@earth.li> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
(struct tipc_link_info)->dest is in network order (__be32), so we must
convert the value to network order before assigning. The problem detected
by sparse:
net/tipc/netlink_compat.c:699:24: warning: incorrect type in assignment (different base types)
net/tipc/netlink_compat.c:699:24: expected restricted __be32 [usertype] dest
net/tipc/netlink_compat.c:699:24: got int
Acked-by: Jon Maloy <jmaloy@redhat.com> Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
This patch fixes the following message which randomly pops up during
glocktop call:
seq_file: buggy .next function table_seq_next did not update position index
The issue is that seq_read_iter() in fs/seq_file.c also needs an
increment of the index in an non next record case as well which this
patch fixes otherwise seq_read_iter() will print out the above message.
Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
If sctp_destroy_sock is called without sock_net(sk)->sctp.addr_wq_lock
held and sp->do_auto_asconf is true, then an element is removed
from the auto_asconf_splist without any proper locking.
This can happen in the following functions:
1. In sctp_accept, if sctp_sock_migrate fails.
2. In inet_create or inet6_create, if there is a bpf program
attached to BPF_CGROUP_INET_SOCK_CREATE which denies
creation of the sctp socket.
This patch is to fix it by moving the auto_asconf init out of
sctp_init_sock(), by which inet_create()/inet6_create() won't
need to operate it in sctp_destroy_sock() when calling
sk_common_release().
It also makes more sense to do auto_asconf init while binding the
first addr, as auto_asconf actually requires an ANY addr bind,
see it in sctp_addr_wq_timeout_handler().
This addresses CVE-2021-23133.
Fixes: 610236587600 ("bpf: Add new cgroup attach type to enable sock modifications") Reported-by: Or Cohen <orcohen@paloaltonetworks.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CPU0 is the thread of sctp_addr_wq_timeout_handler(), and CPU1
is that of sctp_close().
The original issue this commit fixed will be fixed in the next
patch.
Reported-by: syzbot+959223586843e69a2674@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The intent with this code was to return negative error codes but instead
it returns positives.
The problem is how type promotion works with ternary operations. These
functions return long, "ret" is an int and "copied" is a u32. The
negative error code is first cast to u32 so it becomes a high positive and
then cast to long where it's still a positive.
We could fix this by declaring "ret" as a ssize_t but let's just get rid
of the ternaries instead.
Link: https://lkml.kernel.org/r/YIE+/cK1tBzSuQPU@mwanda Fixes: 5bf2b19320ec ("kfifo: add example files to the kernel sample directory") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Stefani Seibold <stefani@seibold.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
In digital_tg_recv_dep_req, it calls nfc_tm_data_received(..,resp).
If nfc_tm_data_received() failed, the callee will free the resp via
kfree_skb() and return error. But in the exit branch, the resp
will be freed again.
My patch sets resp to NULL if nfc_tm_data_received() failed, to
avoid the double free.
Fixes: 1c7a4c24fbfd9 ("NFC Digital: Add target NFC-DEP support") Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
When the error check in ath9k_hw_read_revisions() was added, it checked for
-EIO which is what ath9k_regread() in the ath9k_htc driver uses. However,
for plain ath9k, the register read function uses ioread32(), which just
returns -1 on error. So if such a read fails, it still gets passed through
and ends up as a weird mac revision in the log output.
Fix this by changing ath9k_regread() to return -1 on error like ioread32()
does, and fix the error check to look for that instead of -EIO.
Fixes: 2f90c7e5d094 ("ath9k: Check for errors when reading SREV register") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Reviewed-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/r/20210326180819.142480-1-toke@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>
The bit-masks used for the TXERRCH and RXERRCH (tx and rx error channels)
are incorrect and always lead to a zero result. The mask values are
currently the incorrect post-right shifted values, fix this by setting
them to the currect values.
(I double checked these against the TMS320TCI6482 data sheet, section
5.30, page 127 to ensure I had the correct mask values for the TXERRCH
and RXERRCH fields in the MACSTATUS register).
Addresses-Coverity: ("Operands don't affect result") Fixes: a6286ee630f6 ("net: Add TI DaVinci EMAC driver") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
VMCI feature is not supported in conjunction with the vSphere Fault
Tolerance (FT) feature.
VMware Tools can repeatedly try to create a vsock connection. If FT is
enabled the kernel logs is flooded with the following messages:
qp_alloc_hypercall result = -20
Could not attach to queue pair with -20
"qp_alloc_hypercall result = -20" was hidden by commit e8266c4c3307
("VMCI: Stop log spew when qp allocation isn't possible"), but "Could
not attach to queue pair with -20" is still there flooding the log.
Since the error message can be useful in some cases, print it only once.
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Jorgen Hansen <jhansen@vmware.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
In mwl8k_probe_hw, hw->priv->txq is freed at the first time by
dma_free_coherent() in the call chain:
if(!priv->ap_fw)->mwl8k_init_txqs(hw)->mwl8k_txq_init(hw, i).
Then in err_free_queues of mwl8k_probe_hw, hw->priv->txq is freed
at the second time by mwl8k_txq_deinit(hw, i)->dma_free_coherent().
My patch set txq->txd to NULL after the first free to avoid the
double free.
While adding the invalid IRQ check after calling platform_get_irq(),
I managed to overlook that the driver has a complex error path in its
probe() method, thus a simple *return* couldn't be used. Use a proper
*goto* instead!
The pci_bus->bridge reference may no longer be valid after
pci_bus_remove() resulting in passing a bad value to device_unregister()
for the associated bridge device.
Store the host_bridge reference in a separate variable prior to
pci_bus_remove().
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_irq() (which
takes *unsigned* IRQ #), causing it to fail with -EINVAL, overriding
an original error code. Stop calling devm_request_irq() with invalid
IRQ #s.
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_irq() (which
takes *unsigned* IRQ #), causing it to fail with -EINVAL, overriding
an original error code. Stop calling devm_request_irq() with invalid
IRQ #s.
Fixes: ba92222ed63a ("i2c: jz4780: Add i2c bus controller driver for Ingenic JZ4780") Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_irq() (which
takes *unsigned* IRQ #), causing it to fail with -EINVAL, overriding
an original error code. Stop calling devm_request_irq() with invalid
IRQ #s.
The shifting of the u8 integers rq->caching by 26 bits to
the left will be promoted to a 32 bit signed int and then
sign-extended to a u64. In the event that rq->caching is
greater than 0x1f then all then all the upper 32 bits of
the u64 end up as also being set because of the int
sign-extension. Fix this by casting the u8 values to a
u64 before the 26 bit left shift.
Addresses-Coverity: ("Unintended sign extension") Fixes: 4863dea3fab0 ("net: Adding support for Cavium ThunderX network controller") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently the expression ~nic_conf1 is always true because nic_conf1
is a u16 and according to 6.5.3.3 of the C standard the ~ operator
promotes the u16 to an integer before flipping all the bits. Thus
the top 16 bits of the integer result are all set so the expression
is always true. If the intention was to flip all the bits of nic_conf1
then casting the integer result back to a u16 is a suitabel fix.
Interestingly static analyzers seem to thing a bitwise ! should be
used instead of ~ for this scenario, so I think the original intent
of the expression may need some extra consideration.
Addresses-Coverity: ("Logical vs. bitwise operator") Fixes: c869f77d6abb ("add mt7601u driver") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Jakub Kicinski <kubakici@wp.pl> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/r/20210225183241.1002129-1-colin.king@canonical.com Signed-off-by: Sasha Levin <sashal@kernel.org>
If any of the cipher schemes specified by the driver are invalid, bail
out and fail the registration rather than just warning. Otherwise, we
might later crash when we try to use the invalid cipher scheme, e.g.
if the hdr_len is (significantly) less than the pn_offs + pn_len, we'd
have an out-of-bounds access in RX validation.
When neither CONFIG_PCI nor CONFIG_IBMVIO is set/enabled, iommu.c has a
build error. The fault injection code is not useful in that kernel config,
so make the FAIL_IOMMU option depend on PCI || IBMVIO.
Prevents this build error (warning escalated to error):
../arch/powerpc/kernel/iommu.c:178:30: error: 'fail_iommu_bus_notifier' defined but not used [-Werror=unused-variable]
178 | static struct notifier_block fail_iommu_bus_notifier = {
Fixes: d6b9a81b2a45 ("powerpc: IOMMU fault injection") Reported-by: kernel test robot <lkp@intel.com> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210404192623.10697-1-rdunlap@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org>
There are a few calls of usb_driver_claim_interface() but all of those
miss the proper error checks, as reported by Coverity. This patch
adds those missing checks.
Along with it, replace the magic pointer with -1 with a constant
USB_AUDIO_IFACE_UNUSED for better readability.
Fixes: c3b1e1e8a76f ("NFC: Export NFCID1 from pn533") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
If identical_pvr_fixup() is not inlined, there are two modpost warnings:
WARNING: modpost: vmlinux.o(.text+0x54e8): Section mismatch in reference
from the function identical_pvr_fixup() to the function
.init.text:of_get_flat_dt_prop()
The function identical_pvr_fixup() references
the function __init of_get_flat_dt_prop().
This is often because identical_pvr_fixup lacks a __init
annotation or the annotation of of_get_flat_dt_prop is wrong.
WARNING: modpost: vmlinux.o(.text+0x551c): Section mismatch in reference
from the function identical_pvr_fixup() to the function
.init.text:identify_cpu()
The function identical_pvr_fixup() references
the function __init identify_cpu().
This is often because identical_pvr_fixup lacks a __init
annotation or the annotation of identify_cpu is wrong.
identical_pvr_fixup() calls two functions marked as __init and is only
called by a function marked as __init so it should be marked as __init
as well. At the same time, remove the inline keywork as it is not
necessary to inline this function. The compiler is still free to do so
if it feels it is worthwhile since commit 889b3c1245de ("compiler:
remove CONFIG_OPTIMIZE_INLINING entirely").
There are two "netif_running" checks in this driver. One is in
"lapbeth_xmit" and the other is in "lapbeth_rcv". They serve to make
sure that the LAPB APIs called in these functions are called before
"lapb_unregister" is called by the "ndo_stop" function.
However, these "netif_running" checks are unreliable, because it's
possible that immediately after "netif_running" returns true, "ndo_stop"
is called (which causes "lapb_unregister" to be called).
This patch adds locking to make sure "lapbeth_xmit" and "lapbeth_rcv" can
reliably check and ensure the netif is running while doing their work.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He <xie.he.0141@gmail.com> Acked-by: Martin Schiller <ms@dev.tdt.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Plantronics Blackwire 3220 Series (047f:c056) sends HID reports twice
for each volume key press. This patch adds a quirk to hid-plantronics
for this product ID, which will ignore the second volume key press if
it happens within 5 ms from the last one that was handled.
The patch was tested on the mentioned model only, it shouldn't affect
other models, however, this quirk might be needed for them too.
Auto-repeat (when a key is held pressed) is not affected, because the
rate is about 3 times per second, which is far less frequent than once
in 5 ms.
dev_attr_show() calls _iommu_event_show() via an indirect call but
_iommu_event_show()'s type does not currently match the type of the
show() member in 'struct device_attribute', resulting in a Control Flow
Integrity violation.
If some of the allocations fail between the dev_set_name() and the
device_register() then the name will not be freed. Fix this by
moving dev_set_name() directly in front of the call to device_register().
Fixes: a2aa24734d9d ("HSI: Add common DT binding for HSI client devices") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to request_irq() (which takes
*unsigned* IRQ #s), causing it to fail with -EINVAL (overridden by -ENODEV
further below). Stop calling request_irq() with the invalid IRQ #s.
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to request_irq() (which takes
*unsigned* IRQ #), causing it to fail with -EINVAL, overriding the real
error code. Stop calling request_irq() with the invalid IRQ #s.
Link: https://lore.kernel.org/r/363eb4c8-a3bf-4dc9-2a9e-90f349030a15@omprussia.ru Fixes: 0bb67f181834 ("[SCSI] sun3x_esp: convert to esp_scsi") Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to request_irq() (which takes
*unsigned* IRQ #), causing it to fail with -EINVAL, overriding the real
error code. Stop calling request_irq() with the invalid IRQ #s.
Link: https://lore.kernel.org/r/594aa9ae-2215-49f6-f73c-33bd38989912@omprussia.ru Fixes: 352e921f0dd4 ("[SCSI] jazz_esp: converted to use esp_core") Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
gcc-11 warns about the prototype not exactly matching the function
definition:
drivers/media/usb/dvb-usb/dvb-usb-remote.c:363:20: error: argument 2 of type ‘u8[5]’ {aka ‘unsigned char[5]’} with mismatched bound [-Werror=array-parameter=]
363 | u8 keybuf[5], u32 *event, int *state)
| ~~~^~~~~~~~~
In file included from drivers/media/usb/dvb-usb/dvb-usb-common.h:13,
from drivers/media/usb/dvb-usb/dvb-usb-remote.c:9:
drivers/media/usb/dvb-usb/dvb-usb.h:490:65: note: previously declared as ‘u8[]’ {aka ‘unsigned char[]’}
490 | extern int dvb_usb_nec_rc_key_to_event(struct dvb_usb_device *, u8[], u32 *, int *);
| ^~~~
Iff platform_get_irq() returns 0, ahci_platform_init_host() would return 0
early (as if the call was successful). Override IRQ0 with -EINVAL instead
as the 'libata' regards 0 as "no IRQ" (thus polling) anyway...
The function mv_platform_probe() neglects to check the results of the
calls to platform_get_irq() and irq_of_parse_and_map() and blithely
passes them to ata_host_activate() -- while the latter only checks
for IRQ0 (treating it as a polling mode indicattion) and passes the
negative values to devm_request_irq() causing it to fail as it takes
unsigned values for the IRQ #...
Add to mv_platform_probe() the proper IRQ checks to pass the positive IRQ
#s to ata_host_activate(), propagate upstream the negative error codes,
and override the IRQ0 with -EINVAL (as we don't want the polling mode).
The driver's probe() method is written as if platform_get_irq() returns 0
on error, while actually it returns a negative error code (with all the
other values considered valid IRQs). Rewrite the driver's IRQ checking
code to pass the positive IRQ #s to ata_host_activate(), propagate errors
upstream, and treat IRQ0 as error, returning -EINVAL, as the libata code
treats 0 as an indication that polling should be used anyway...
The driver's probe() method is written as if platform_get_irq() returns 0
on error, while actually it returns a negative error code (with all the
other values considered valid IRQs). Rewrite the driver's IRQ checking code
to pass the positive IRQ #s to ata_host_activate(), propagate upstream
-EPROBE_DEFER, and set up the driver to polling mode on (negative) errors
and IRQ0 (libata treats IRQ #0 as a polling mode anyway)...
There a 3 array for-loops that don't check the upper bounds of the
index into arrays and this may lead to potential out-of-bounds
reads. Fix this by adding array size upper bounds checks to be
full safe.
Addresses-Coverity: ("Out-of-bounds read")
Link: https://lore.kernel.org/linux-media/20201007121628.20676-1-colin.king@canonical.com Fixes: 333829110f1d ("[media] m88rs6000t: add new dvb-s/s2 tuner for integrated chip M88RS6000") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently the chroma_flags and alpha_flags are being zero'd with a bit-wise
mask and the following statement should be bit-wise or'ing in the new flag
bits but instead is making a direct assignment. Fix this by using the |=
operator rather than an assignment.
Addresses-Coverity: ("Unused value")
Fixes: ef834f7836ec ("[media] vivid: add the video capture and output parts") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
int main(int argc, char *argv[])
{
int i;
int fd[10];
for (i = 0; i < 10; i++)
fd[i] = open("/dev/ttyprintk", O_WRONLY);
ioctl(fd[0], TIOCVHANGUP);
for (i = 0; i < 10; i++)
close(fd[i]);
close(open("/dev/ttyprintk", O_WRONLY));
return 0;
}
----------
When TTY hangup happens, port->count needs to be reset via
"struct tty_operations"->hangup callback.
TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
serial devices is only useful for setting the close_delay and
closing_wait parameters.
A non-privileged user has only ever been able to set the since long
deprecated ASYNC_SPD flags and trying to change any other *supported*
feature should result in -EPERM being returned. Setting the current
values for any supported features should return success.
Fix the cdc-acm implementation which instead indicated that the
TIOCSSERIAL ioctl was not even implemented when a non-privileged user
set the current values.
Fixes: ba2d8ce9db0a ("cdc-acm: implement TIOCSSERIAL to avoid blocking close(2)") Acked-by: Oliver Neukum <oneukum@suse.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210408131602.27956-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
In adf_create_ring, if the callee adf_init_ring() failed, the callee will
free the ring->base_addr by dma_free_coherent() and return -EFAULT. Then
adf_create_ring will goto err and the ring->base_addr will be freed again
in adf_cleanup_ring().
My patch sets ring->base_addr to NULL after the first freed to avoid the
double free.
The for-loop iterates with a u8 loop counter i and compares this
with the loop upper limit of riv->ieee80211->LinkDetectInfo.SlotNum
that is a u16 type. There is a potential infinite loop if SlotNum
is larger than the u8 loop counter. Fix this by making the loop
counter the same type as SlotNum.
Addresses-Coverity: ("Infinite loop") Fixes: 8fc8598e61f6 ("Staging: Added Realtek rtl8192u driver to staging") Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20210407150308.496623-1-colin.king@canonical.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The function adf_isr_resource_alloc() is not unwinding correctly in case
of error.
This patch fixes the error paths and propagate the errors to the caller.
Fixes: 7afa232e76ce ("crypto: qat - Intel(R) QAT DH895xcc accelerator") Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> Reviewed-by: Marco Chiappero <marco.chiappero@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
MEMLOCK, MEMUNLOCK and OTPLOCK modify protection bits. Thus require
write permission. Depending on the hardware MEMLOCK might even be
write-once, e.g. for SPI-NOR flashes with their WP# tied to GND. OTPLOCK
is always write-once.
MEMSETBADBLOCK modifies the bad block table.
Fixes: f7e6b19bc764 ("mtd: properly check all write ioctls for permissions") Signed-off-by: Michael Walle <michael@walle.cc> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Rafał Miłecki <rafal@milecki.pl> Acked-by: Richard Weinberger <richard@nod.at> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/linux-mtd/20210303155735.25887-1-michael@walle.cc Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently it leaves unhandled interrupts unmasked, but those are never
acked. In the case of a "device idle" interrupt, this leads to an
effectively frozen system until plugging it in.
When the EP0 IN request was not completed but less than a packet sent,
it would complete the request successfully. That doesn't make sense
and can't really happen as fotg210_start_dma always sends
min(length, maxpkt) bytes.
For a 134 Byte packet, it sends the first two 64 Byte packets just fine,
but then notice that less than a packet is remaining and call fotg210_done
without actually sending the rest.
For a 75 Byte request, it would send the first 64 separately, then detect
that the remaining 11 Byte fit into a single DMA, but due to this bug set
the length to the original 75 Bytes. This leads to a DMA failure (which is
ignored...) and the request completes without the remaining bytes having
been sent.
adf_vf_isr_resource_alloc() is not unwinding correctly when error
happens and it want to release uninitialized resources.
To fix this, only release initialized resources.
DMA mapping might fail, we have to check it with dma_mapping_error().
Otherwise DMA-API is not happy:
DMA-API: pch_udc 0000:02:02.4: device driver failed to check map error[device address=0x00000000027ee678] [size=64 bytes] [mapped as single]
Fixes: abab0c67c061 ("usb: pch_udc: Fixed issue which does not work with g_serial") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20210323153626.54908-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Either way ~0 will be in the correct byte order, hence
replace cpu_to_le32() by lower_32_bits(). Moreover,
it makes sparse happy, otherwise it complains:
.../pch_udc.c:1813:27: warning: incorrect type in assignment (different base types)
.../pch_udc.c:1813:27: expected unsigned int [usertype] dataptr
.../pch_udc.c:1813:27: got restricted __le32 [usertype]
The Maxim PMIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
The Maxim PMIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
Fixes: 47580e8d94c2 ("ARM: dts: Specify MAX77686 pmic interrupt for exynos5250-smdk5250") Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/r/20201210212534.216197-8-krzk@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently the array gpmc_cs is indexed by cs before it cs is range checked
and the pointer read from this out-of-index read is dereferenced. Fix this
by performing the range check on cs before the read and the following
pointer dereference.
Addresses-Coverity: ("Negative array index read") Fixes: 9ed7a776eb50 ("ARM: OMAP2+: Fix support for multiple devices on a GPMC chip select") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20210223193821.17232-1-colin.king@canonical.com Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The commit d3cb25a12138 ("usb: gadget: udc: fix spin_lock in pch_udc")
obviously was not thought through and had made the situation even worse
than it was before. Two changes after almost reverted it. but a few
leftovers have been left as it. With this revert d3cb25a12138 completely.
While at it, narrow down the scope of unlocked section to prevent
potential race when prot_stall is assigned.
The quirk entry for Uniwill ECS M31EI is with the PCI SSID device 0,
which means matching with all. That is, it's essentially equivalent
with SND_PCI_QUIRK_VENDOR(0x1584), which also matches with the
previous entry for Haier W18 applying the very same quirk.
Let's unify them with the single vendor-quirk entry.
Just re-order the alc269_fixup_tbl[] entries for Sony devices for
avoiding the oversight of the duplicated or unapplied item in future.
No functional changes.
Also Cc-to-stable for the further patch applications.
Just re-order the alc882_fixup_tbl[] entries for Sony devices for
avoiding the oversight of the duplicated or unapplied item in future.
No functional changes.
Also Cc-to-stable for the further patch applications.
Just re-order the alc882_fixup_tbl[] entries for Acer devices for
avoiding the oversight of the duplicated or unapplied item in future.
No functional changes.
Also Cc-to-stable for the further patch applications.
Currently the ioctl command RADEON_INFO_SI_BACKEND_ENABLED_MASK can
copy back uninitialised data in value_tmp that pointer *value points
to. This can occur when rdev->family is less than CHIP_BONAIRE and
less than CHIP_TAHITI. Fix this by adding in a missing -EINVAL
so that no invalid value is copied back to userspace.
Addresses-Coverity: ("Uninitialized scalar variable) Cc: stable@vger.kernel.org # 3.13+ Fixes: 439a1cfffe2c ("drm/radeon: expose render backend mask to the userspace") Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we overflow the maximum number of BSS entries and free the
new entry, drop it from any hidden_list that it may have been
added to in the code above or in cfg80211_combine_bsses().
commit d3374825ce57 ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.
This patch changes md_open returning from -ERESTARTSYS to -EBUSY, which
will break the infinitely retry when md_open enter racing area.
This patch is partly fix soft lockup issue, full fix needs mddev_find
is split into two functions: mddev_find & mddev_find_or_alloc. And
md_open should call new mddev_find (it only does searching job).
For more detail, please refer with Christoph's "split mddev_find" patch
in later commits.
*** env ***
kvm-qemu VM 2C1G with 2 iscsi luns
kernel should be non-preempt
I use mdcluster env to trigger soft lockup, but it isn't mdcluster
speical bug. To stop md array in mdcluster env will do more jobs than
non-cluster array, which will leave enough time/gap to allow kernel to
run md_open.
"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
--monitor" by default. When "mdadm -Ss" is running, the stop action will
wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
info from /proc/mdstat. This time mddev in kernel still exist, so
/proc/mdstat still show md device, which makes "mdadm --monitor" to open
/dev/md0.
The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
open action will trigger md_open which is creating action. Racing is
happening.
```
<thread 1>: "mdadm -Ss"
md_release
mddev_put deletes mddev from all_mddevs
queue_work for mddev_delayed_delete
at this time, "/dev/md0" is still available for opening
<thread 2>: "mdadm --monitor ..."
md_open
+ mddev_find can't find mddev of /dev/md0, and create a new mddev and
| return.
+ trigger "if (mddev->gendisk != bdev->bd_disk)" and return
-ERESTARTSYS.
```
In non-preempt kernel, <thread 2> is occupying on current CPU. and
mddev_delayed_delete which was created in <thread 1> also can't be
schedule.
In preempt kernel, it can also trigger above racing. But kernel doesn't
allow one thread running on a CPU all the time. after <thread 2> running
some time, the later "mdadm -A" (refer above script line 13) will call
md_alloc to alloc a new gendisk for mddev. it will break md_open
statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
the soft lockup is broken.
Cc: stable@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Zhao Heming <heming.zhao@suse.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It was reported that a fix to the ring buffer recursion detection would
cause a hung machine when performing suspend / resume testing. The
following backtrace was extracted from debugging that case:
Since the fix to the recursion detection would allow a single recursion to
happen while tracing, this lead to the trace_clock_global() taking a spin
lock and then trying to take it again:
ring_buffer_lock_reserve() {
trace_clock_global() {
arch_spin_lock() {
queued_spin_lock_slowpath() {
/* lock taken */
(something else gets traced by function graph tracer)
ring_buffer_lock_reserve() {
trace_clock_global() {
arch_spin_lock() {
queued_spin_lock_slowpath() {
/* DEAD LOCK! */
Tracing should *never* block, as it can lead to strange lockups like the
above.
Restructure the trace_clock_global() code to instead of simply taking a
lock to update the recorded "prev_time" simply use it, as two events
happening on two different CPUs that calls this at the same time, really
doesn't matter which one goes first. Use a trylock to grab the lock for
updating the prev_time, and if it fails, simply try again the next time.
If it failed to be taken, that means something else is already updating
it.
Link: https://lkml.kernel.org/r/20210430121758.650b6e8a@gandalf.local.home Cc: stable@vger.kernel.org Tested-by: Konstantin Kharlamov <hi-angel@yandex.ru> Tested-by: Todd Brandt <todd.e.brandt@linux.intel.com> Fixes: b02414c8f045 ("ring-buffer: Fix recursion protection transitions between interrupt context") # started showing the problem Fixes: 14131f2f98ac3 ("tracing: implement trace_clock_*() APIs") # where the bug happened
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212761 Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The default max PID is set by PID_MAX_DEFAULT, and the tracing
infrastructure uses this number to map PIDs to the comm names of the
tasks, such output of the trace can show names from the recorded PIDs in
the ring buffer. This mapping is also exported to user space via the
"saved_cmdlines" file in the tracefs directory.
But currently the mapping expects the PIDs to be less than
PID_MAX_DEFAULT, which is the default maximum and not the real maximum.
Recently, systemd will increases the maximum value of a PID on the system,
and when tasks are traced that have a PID higher than PID_MAX_DEFAULT, its
comm is not recorded. This leads to the entire trace to have "<...>" as
the comm name, which is pretty useless.
Instead, keep the array mapping the size of PID_MAX_DEFAULT, but instead
of just mapping the index to the comm, map a mask of the PID
(PID_MAX_DEFAULT - 1) to the comm, and find the full PID from the
map_cmdline_to_pid array (that already exists).
This bug goes back to the beginning of ftrace, but hasn't been an issue
until user space started increasing the maximum value of PIDs.