In the Linux kernel, the following vulnerability has been resolved:
rtla: Avoid record NULL pointer dereference
Fix the following null/deref_null.cocci errors:
./tools/tracing/rtla/src/osnoise_hist.c:870:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/osnoise_top.c:650:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/timerlat_hist.c:905:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/timerlat_top.c:700:31-36: ERROR: record is NULL but dereferenced.
"record" is NULL before calling osnoise_init_trace_tool.
Add a tag "out_free" to avoid dereferring a NULL pointer.
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: idxd: Fix the error handling path in idxd_cdev_register()
If a call to alloc_chrdev_region() fails, the already allocated resources
are leaking.
Add the needed error handling path to fix the leak.
In the Linux kernel, the following vulnerability has been resolved:
net: annotate races around sk->sk_bound_dev_if
UDP sendmsg() is lockless, and reads sk->sk_bound_dev_if while
this field can be changed by another thread.
Adds minimal annotations to avoid KCSAN splats for UDP.
Following patches will add more annotations to potential lockless readers.
BUG: KCSAN: data-race in __ip6_datagram_connect / udpv6_sendmsg
write to 0xffff888136d47a94 of 4 bytes by task 7681 on cpu 0:
__ip6_datagram_connect+0x6e2/0x930 net/ipv6/datagram.c:221
ip6_datagram_connect+0x2a/0x40 net/ipv6/datagram.c:272
inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576
__sys_connect_file net/socket.c:1900 [inline]
__sys_connect+0x197/0x1b0 net/socket.c:1917
__do_sys_connect net/socket.c:1927 [inline]
__se_sys_connect net/socket.c:1924 [inline]
__x64_sys_connect+0x3d/0x50 net/socket.c:1924
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
read to 0xffff888136d47a94 of 4 bytes by task 7670 on cpu 1:
udpv6_sendmsg+0xc60/0x16e0 net/ipv6/udp.c:1436
inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:652
sock_sendmsg_nosec net/socket.c:705 [inline]
sock_sendmsg net/socket.c:725 [inline]
____sys_sendmsg+0x39a/0x510 net/socket.c:2413
___sys_sendmsg net/socket.c:2467 [inline]
__sys_sendmmsg+0x267/0x4c0 net/socket.c:2553
__do_sys_sendmmsg net/socket.c:2582 [inline]
__se_sys_sendmmsg net/socket.c:2579 [inline]
__x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
value changed: 0x00000000 -> 0xffffff9b
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7670 Comm: syz-executor.3 Tainted: G W 5.18.0-rc1-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
I chose to not add Fixes: tag because race has minor consequences
and stable teams busy enough.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix race condition between ext4_write and ext4_convert_inline_data
Hulk Robot reported a BUG_ON:
==================================================================
EXT4-fs error (device loop3): ext4_mb_generate_buddy:805: group 0,
block bitmap and bg descriptor inconsistent: 25 vs 31513 free clusters
kernel BUG at fs/ext4/ext4_jbd2.c:53!
invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 PID: 25371 Comm: syz-executor.3 Not tainted 5.10.0+ #1
RIP: 0010:ext4_put_nojournal fs/ext4/ext4_jbd2.c:53 [inline]
RIP: 0010:__ext4_journal_stop+0x10e/0x110 fs/ext4/ext4_jbd2.c:116
[...]
Call Trace:
ext4_write_inline_data_end+0x59a/0x730 fs/ext4/inline.c:795
generic_perform_write+0x279/0x3c0 mm/filemap.c:3344
ext4_buffered_write_iter+0x2e3/0x3d0 fs/ext4/file.c:270
ext4_file_write_iter+0x30a/0x11c0 fs/ext4/file.c:520
do_iter_readv_writev+0x339/0x3c0 fs/read_write.c:732
do_iter_write+0x107/0x430 fs/read_write.c:861
vfs_writev fs/read_write.c:934 [inline]
do_pwritev+0x1e5/0x380 fs/read_write.c:1031
[...]
==================================================================
Above issue may happen as follows:
cpu1 cpu2
__________________________|__________________________
do_pwritev
vfs_writev
do_iter_write
ext4_file_write_iter
ext4_buffered_write_iter
generic_perform_write
ext4_da_write_begin
vfs_fallocate
ext4_fallocate
ext4_convert_inline_data
ext4_convert_inline_data_nolock
ext4_destroy_inline_data_nolock
clear EXT4_STATE_MAY_INLINE_DATA
ext4_map_blocks
ext4_ext_map_blocks
ext4_mb_new_blocks
ext4_mb_regular_allocator
ext4_mb_good_group_nolock
ext4_mb_init_group
ext4_mb_init_cache
ext4_mb_generate_buddy --> error
ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)
ext4_restore_inline_data
set EXT4_STATE_MAY_INLINE_DATA
ext4_block_write_begin
ext4_da_write_end
ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)
ext4_write_inline_data_end
handle=NULL
ext4_journal_stop(handle)
__ext4_journal_stop
ext4_put_nojournal(handle)
ref_cnt = (unsigned long)handle
BUG_ON(ref_cnt == 0) ---> BUG_ON
The lock held by ext4_convert_inline_data is xattr_sem, but the lock
held by generic_perform_write is i_rwsem. Therefore, the two locks can
be concurrent.
To solve above issue, we add inode_lock() for ext4_convert_inline_data().
At the same time, move ext4_convert_inline_data() in front of
ext4_punch_hole(), remove similar handling from ext4_punch_hole().
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix memory leak in parse_apply_sb_mount_options()
If processing the on-disk mount options fails after any memory was
allocated in the ext4_fs_context, e.g. s_qf_names, then this memory is
leaked. Fix this by calling ext4_fc_free() instead of kfree() directly.
Reproducer:
mkfs.ext4 -F /dev/vdc
tune2fs /dev/vdc -E mount_opts=usrjquota=file
echo clear > /sys/kernel/debug/kmemleak
mount /dev/vdc /vdc
echo scan > /sys/kernel/debug/kmemleak
sleep 5
echo scan > /sys/kernel/debug/kmemleak
cat /sys/kernel/debug/kmemleak
In the Linux kernel, the following vulnerability has been resolved:
block: Fix potential deadlock in blk_ia_range_sysfs_show()
When being read, a sysfs attribute is already protected against removal
with the kobject node active reference counter. As a result, in
blk_ia_range_sysfs_show(), there is no need to take the queue sysfs
lock when reading the value of a range attribute. Using the queue sysfs
lock in this function creates a potential deadlock situation with the
disk removal, something that a lockdep signals with a splat when the
device is removed:
[ 760.703551] Possible unsafe locking scenario:
[ 760.703551]
[ 760.703554] CPU0 CPU1
[ 760.703556] ---- ----
[ 760.703558] lock(&q->sysfs_lock);
[ 760.703565] lock(kn->active#385);
[ 760.703573] lock(&q->sysfs_lock);
[ 760.703579] lock(kn->active#385);
[ 760.703587]
[ 760.703587] *** DEADLOCK ***
Solve this by removing the mutex_lock()/mutex_unlock() calls from
blk_ia_range_sysfs_show().
In the Linux kernel, the following vulnerability has been resolved:
staging: r8188eu: prevent ->Ssid overflow in rtw_wx_set_scan()
This code has a check to prevent read overflow but it needs another
check to prevent writing beyond the end of the ->Ssid[] array.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/hfi1: Fix potential integer multiplication overflow errors
When multiplying of different types, an overflow is possible even when
storing the result in a larger type. This is because the conversion is
done after the multiplication. So arithmetic overflow and thus in
incorrect value is possible.
Correct an instance of this in the inter packet delay calculation. Fix by
ensuring one of the operands is u64 which will promote the other to u64 as
well ensuring no overflow.
In the Linux kernel, the following vulnerability has been resolved:
lib/string_helpers: fix not adding strarray to device's resource list
Add allocated strarray to device's resource list. This is a must to
automatically release strarray when the device disappears.
Without this fix we have a memory leak in the few drivers which use
devm_kasprintf_strarray().
In the Linux kernel, the following vulnerability has been resolved:
md: Don't set mddev private to NULL in raid0 pers->free
In normal stop process, it does like this:
do_md_stop
|
__md_stop (pers->free(); mddev->private=NULL)
|
md_free (free mddev)
__md_stop sets mddev->private to NULL after pers->free. The raid device
will be stopped and mddev memory is free. But in reshape, it doesn't
free the mddev and mddev will still be used in new raid.
In reshape, it first sets mddev->private to new_pers and then runs
old_pers->free(). Now raid0 sets mddev->private to NULL in raid0_free.
The new raid can't work anymore. It will panic when dereference
mddev->private because of NULL pointer dereference.
It can panic like this:
[63010.814972] kernel BUG at drivers/md/raid10.c:928!
[63010.819778] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[63010.825011] CPU: 3 PID: 44437 Comm: md0_resync Kdump: loaded Not tainted 5.14.0-86.el9.x86_64 #1
[63010.833789] Hardware name: Dell Inc. PowerEdge R6415/07YXFK, BIOS 1.15.0 09/11/2020
[63010.841440] RIP: 0010:raise_barrier+0x161/0x170 [raid10]
[63010.865508] RSP: 0018:ffffc312408bbc10 EFLAGS: 00010246
[63010.870734] RAX: 0000000000000000 RBX: ffffa00bf7d39800 RCX: 0000000000000000
[63010.877866] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffa00bf7d39800
[63010.884999] RBP: 0000000000000000 R08: fffffa4945e74400 R09: 0000000000000000
[63010.892132] R10: ffffa00eed02f798 R11: 0000000000000000 R12: ffffa00bbc435200
[63010.899266] R13: ffffa00bf7d39800 R14: 0000000000000400 R15: 0000000000000003
[63010.906399] FS: 0000000000000000(0000) GS:ffffa00eed000000(0000) knlGS:0000000000000000
[63010.914485] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[63010.920229] CR2: 00007f5cfbe99828 CR3: 0000000105efe000 CR4: 00000000003506e0
[63010.927363] Call Trace:
[63010.929822] ? bio_reset+0xe/0x40
[63010.933144] ? raid10_alloc_init_r10buf+0x60/0xa0 [raid10]
[63010.938629] raid10_sync_request+0x756/0x1610 [raid10]
[63010.943770] md_do_sync.cold+0x3e4/0x94c
[63010.947698] md_thread+0xab/0x160
[63010.951024] ? md_write_inc+0x50/0x50
[63010.954688] kthread+0x149/0x170
[63010.957923] ? set_kthread_struct+0x40/0x40
[63010.962107] ret_from_fork+0x22/0x30
Removing the code that sets mddev->private to NULL in raid0 can fix
problem.
In the Linux kernel, the following vulnerability has been resolved:
tty: goldfish: Use tty_port_destroy() to destroy port
In goldfish_tty_probe(), the port initialized through tty_port_init()
should be destroyed in error paths.In goldfish_tty_remove(), qtty->port
also should be destroyed or else might leak resources.
Fix the above by calling tty_port_destroy().
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: gadget: Replace list_for_each_entry_safe() if using giveback
The list_for_each_entry_safe() macro saves the current item (n) and
the item after (n+1), so that n can be safely removed without
corrupting the list. However, when traversing the list and removing
items using gadget giveback, the DWC3 lock is briefly released,
allowing other routines to execute. There is a situation where, while
items are being removed from the cancelled_list using
dwc3_gadget_ep_cleanup_cancelled_requests(), the pullup disable
routine is running in parallel (due to UDC unbind). As the cleanup
routine removes n, and the pullup disable removes n+1, once the
cleanup retakes the DWC3 lock, it references a request who was already
removed/handled. With list debug enabled, this leads to a panic.
Ensure all instances of the macro are replaced where gadget giveback
is used.
Example call stack:
Thread#1:
__dwc3_gadget_ep_set_halt() - CLEAR HALT
-> dwc3_gadget_ep_cleanup_cancelled_requests()
->list_for_each_entry_safe()
->dwc3_gadget_giveback(n)
->dwc3_gadget_del_and_unmap_request()- n deleted[cancelled_list]
->spin_unlock
->Thread#2 executes
...
->dwc3_gadget_giveback(n+1)
->Already removed!
Thread#2:
dwc3_gadget_pullup()
->waiting for dwc3 spin_lock
...
->Thread#1 released lock
->dwc3_stop_active_transfers()
->dwc3_remove_requests()
->fetches n+1 item from cancelled_list (n removed by Thread#1)
->dwc3_gadget_giveback()
->dwc3_gadget_del_and_unmap_request()- n+1 deleted[cancelled_list]
->spin_unlock
In the Linux kernel, the following vulnerability has been resolved:
blk-iolatency: Fix inflight count imbalances and IO hangs on offline
iolatency needs to track the number of inflight IOs per cgroup. As this
tracking can be expensive, it is disabled when no cgroup has iolatency
configured for the device. To ensure that the inflight counters stay
balanced, iolatency_set_limit() freezes the request_queue while manipulating
the enabled counter, which ensures that no IO is in flight and thus all
counters are zero.
Unfortunately, iolatency_set_limit() isn't the only place where the enabled
counter is manipulated. iolatency_pd_offline() can also dec the counter and
trigger disabling. As this disabling happens without freezing the q, this
can easily happen while some IOs are in flight and thus leak the counts.
This can be easily demonstrated by turning on iolatency on an one empty
cgroup while IOs are in flight in other cgroups and then removing the
cgroup. Note that iolatency shouldn't have been enabled elsewhere in the
system to ensure that removing the cgroup disables iolatency for the whole
device.
The following keeps flipping on and off iolatency on sda:
echo +io > /sys/fs/cgroup/cgroup.subtree_control
while true; do
mkdir -p /sys/fs/cgroup/test
echo '8:0 target=100000' > /sys/fs/cgroup/test/io.latency
sleep 1
rmdir /sys/fs/cgroup/test
sleep 1
done
and there's concurrent fio generating direct rand reads:
fio --name test --filename=/dev/sda --direct=1 --rw=randread \
--runtime=600 --time_based --iodepth=256 --numjobs=4 --bs=4k
while monitoring with the following drgn script:
while True:
for css in css_for_each_descendant_pre(prog['blkcg_root'].css.address_of_()):
for pos in hlist_for_each(container_of(css, 'struct blkcg', 'css').blkg_list):
blkg = container_of(pos, 'struct blkcg_gq', 'blkcg_node')
pd = blkg.pd[prog['blkcg_policy_iolatency'].plid]
if pd.value_() == 0:
continue
iolat = container_of(pd, 'struct iolatency_grp', 'pd')
inflight = iolat.rq_wait.inflight.counter.value_()
if inflight:
print(f'inflight={inflight} {disk_name(blkg.q.disk).decode("utf-8")} '
f'{cgroup_path(css.cgroup).decode("utf-8")}')
time.sleep(1)
The monitoring output looks like the following:
inflight=1 sda /user.slice
inflight=1 sda /user.slice
...
inflight=14 sda /user.slice
inflight=13 sda /user.slice
inflight=17 sda /user.slice
inflight=15 sda /user.slice
inflight=18 sda /user.slice
inflight=17 sda /user.slice
inflight=20 sda /user.slice
inflight=19 sda /user.slice <- fio stopped, inflight stuck at 19
inflight=19 sda /user.slice
inflight=19 sda /user.slice
If a cgroup with stuck inflight ends up getting throttled, the throttled IOs
will never get issued as there's no completion event to wake it up leading
to an indefinite hang.
This patch fixes the bug by unifying enable handling into a work item which
is automatically kicked off from iolatency_set_min_lat_nsec() which is
called from both iolatency_set_limit() and iolatency_pd_offline() paths.
Punting to a work item is necessary as iolatency_pd_offline() is called
under spinlocks while freezing a request_queue requires a sleepable context.
This also simplifies the code reducing LOC sans the comments and avoids the
unnecessary freezes which were happening whenever a cgroup's latency target
is newly set or cleared.
In the Linux kernel, the following vulnerability has been resolved:
serial: 8250_aspeed_vuart: Fix potential NULL dereference in aspeed_vuart_probe
platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved:
usb: usbip: fix a refcount leak in stub_probe()
usb_get_dev() is called in stub_device_alloc(). When stub_probe() fails
after that, usb_put_dev() needs to be called to release the reference.
Fix this by moving usb_put_dev() to sdev_free error path handling.
Find this by code review.
In the Linux kernel, the following vulnerability has been resolved:
watchdog: rzg2l_wdt: Fix 32bit overflow issue
The value of timer_cycle_us can be 0 due to 32bit overflow.
For eg:- If we assign the counter value "0xfff" for computing
maxval.
This patch fixes this issue by appending ULL to 1024, so that
it is promoted to 64bit.
This patch also fixes the warning message, 'watchdog: Invalid min and
max timeout values, resetting to 0!'.
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: ti: am65-cpsw-nuss: Fix some refcount leaks
of_get_child_by_name() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
am65_cpsw_init_cpts() and am65_cpsw_nuss_probe() don't release
the refcount in error case.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
soc: rockchip: Fix refcount leak in rockchip_grf_init
of_find_matching_node_and_match returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid f2fs_bug_on() in dec_valid_node_count()
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215897
I have encountered a bug in F2FS file system in kernel v5.17.
The kernel should enable CONFIG_KASAN=y and CONFIG_KASAN_INLINE=y. You can
reproduce the bug by running the following commands:
The kernel message is shown below:
kernel BUG at fs/f2fs/f2fs.h:2511!
Call Trace:
f2fs_remove_inode_page+0x2a2/0x830
f2fs_evict_inode+0x9b7/0x1510
evict+0x282/0x4e0
do_unlinkat+0x33a/0x540
__x64_sys_unlinkat+0x8e/0xd0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is: .total_valid_block_count or .total_valid_node_count
could fuzzed to zero, then once dec_valid_node_count() was called, it
will cause BUG_ON(), this patch fixes to print warning info and set
SBI_NEED_FSCK into CP instead of panic.
In the Linux kernel, the following vulnerability has been resolved:
sfc: fix considering that all channels have TX queues
Normally, all channels have RX and TX queues, but this is not true if
modparam efx_separate_tx_channels=1 is used. In that cases, some
channels only have RX queues and others only TX queues (or more
preciselly, they have them allocated, but not initialized).
Fix efx_channel_has_tx_queues to return the correct value for this case
too.
Messages shown at probe time before the fix:
sfc 0000:03:00.0 ens6f0np0: MC command 0x82 inlen 544 failed rc=-22 (raw=0) arg=0
------------[ cut here ]------------
netdevice: ens6f0np0: failed to initialise TXQ -1
WARNING: CPU: 1 PID: 626 at drivers/net/ethernet/sfc/ef10.c:2393 efx_ef10_tx_init+0x201/0x300 [sfc]
[...] stripped
RIP: 0010:efx_ef10_tx_init+0x201/0x300 [sfc]
[...] stripped
Call Trace:
efx_init_tx_queue+0xaa/0xf0 [sfc]
efx_start_channels+0x49/0x120 [sfc]
efx_start_all+0x1f8/0x430 [sfc]
efx_net_open+0x5a/0xe0 [sfc]
__dev_open+0xd0/0x190
__dev_change_flags+0x1b3/0x220
dev_change_flags+0x21/0x60
[...] stripped
Messages shown at remove time before the fix:
sfc 0000:03:00.0 ens6f0np0: failed to flush 10 queues
sfc 0000:03:00.0 ens6f0np0: failed to flush queues
In the Linux kernel, the following vulnerability has been resolved:
scsi: sd: Fix potential NULL pointer dereference
If sd_probe() sees an early error before sdkp->device is initialized,
sd_zbc_release_disk() is called. This causes a NULL pointer dereference
when sd_is_zoned() is called inside that function. Avoid this by removing
the call to sd_zbc_release_disk() in sd_probe() error path.
This change is safe and does not result in zone information memory leakage
because the zone information for a zoned disk is allocated only when
sd_revalidate_disk() is called, at which point sdkp->disk_dev is fully set,
resulting in sd_disk_release() being called when needed to cleanup a disk
zone information using sd_zbc_release_disk().
In the Linux kernel, the following vulnerability has been resolved:
rtc: mt6397: check return value after calling platform_get_resource()
It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.
In the Linux kernel, the following vulnerability has been resolved:
tipc: check attribute length for bearer name
syzbot reported uninit-value:
=====================================================
BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:644 [inline]
BUG: KMSAN: uninit-value in string+0x4f9/0x6f0 lib/vsprintf.c:725
string_nocheck lib/vsprintf.c:644 [inline]
string+0x4f9/0x6f0 lib/vsprintf.c:725
vsnprintf+0x2222/0x3650 lib/vsprintf.c:2806
vprintk_store+0x537/0x2150 kernel/printk/printk.c:2158
vprintk_emit+0x28b/0xab0 kernel/printk/printk.c:2256
vprintk_default+0x86/0xa0 kernel/printk/printk.c:2283
vprintk+0x15f/0x180 kernel/printk/printk_safe.c:50
_printk+0x18d/0x1cf kernel/printk/printk.c:2293
tipc_enable_bearer net/tipc/bearer.c:371 [inline]
__tipc_nl_bearer_enable+0x2022/0x22a0 net/tipc/bearer.c:1033
tipc_nl_bearer_enable+0x6c/0xb0 net/tipc/bearer.c:1042
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
- Do sanity check the attribute length for TIPC_NLA_BEARER_NAME.
- Do not use 'illegal name' in printing message.
In the Linux kernel, the following vulnerability has been resolved:
watchdog: ts4800_wdt: Fix refcount leak in ts4800_wdt_probe
of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() in some error paths.
In the Linux kernel, the following vulnerability has been resolved:
tcp: tcp_rtx_synack() can be called from process context
Laurent reported the enclosed report [1]
This bug triggers with following coditions:
0) Kernel built with CONFIG_DEBUG_PREEMPT=y
1) A new passive FastOpen TCP socket is created.
This FO socket waits for an ACK coming from client to be a complete
ESTABLISHED one.
2) A socket operation on this socket goes through lock_sock()
release_sock() dance.
3) While the socket is owned by the user in step 2),
a retransmit of the SYN is received and stored in socket backlog.
4) At release_sock() time, the socket backlog is processed while
in process context.
5) A SYNACK packet is cooked in response of the SYN retransmit.
6) -> tcp_rtx_synack() is called in process context.
Before blamed commit, tcp_rtx_synack() was always called from BH handler,
from a timer handler.
Fix this by using TCP_INC_STATS() & NET_INC_STATS()
which do not assume caller is in non preemptible context.
[1]
BUG: using __this_cpu_add() in preemptible [00000000] code: epollpep/2180
caller is tcp_rtx_synack.part.0+0x36/0xc0
CPU: 10 PID: 2180 Comm: epollpep Tainted: G OE 5.16.0-0.bpo.4-amd64 #1 Debian 5.16.12-1~bpo11+1
Hardware name: Supermicro SYS-5039MC-H8TRF/X11SCD-F, BIOS 1.7 11/23/2021
Call Trace:
<TASK>
dump_stack_lvl+0x48/0x5e
check_preemption_disabled+0xde/0xe0
tcp_rtx_synack.part.0+0x36/0xc0
tcp_rtx_synack+0x8d/0xa0
? kmem_cache_alloc+0x2e0/0x3e0
? apparmor_file_alloc_security+0x3b/0x1f0
inet_rtx_syn_ack+0x16/0x30
tcp_check_req+0x367/0x610
tcp_rcv_state_process+0x91/0xf60
? get_nohz_timer_target+0x18/0x1a0
? lock_timer_base+0x61/0x80
? preempt_count_add+0x68/0xa0
tcp_v4_do_rcv+0xbd/0x270
__release_sock+0x6d/0xb0
release_sock+0x2b/0x90
sock_setsockopt+0x138/0x1140
? __sys_getsockname+0x7e/0xc0
? aa_sk_perm+0x3e/0x1a0
__sys_setsockopt+0x198/0x1e0
__x64_sys_setsockopt+0x21/0x30
do_syscall_64+0x38/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
In the Linux kernel, the following vulnerability has been resolved:
driver core: fix deadlock in __device_attach
In __device_attach function, The lock holding logic is as follows:
...
__device_attach
device_lock(dev) // get lock dev
async_schedule_dev(__device_attach_async_helper, dev); // func
async_schedule_node
async_schedule_node_domain(func)
entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
/* when fail or work limit, sync to execute func, but
__device_attach_async_helper will get lock dev as
well, which will lead to A-A deadlock. */
if (!entry || atomic_read(&entry_count) > MAX_WORK) {
func;
else
queue_work_node(node, system_unbound_wq, &entry->work)
device_unlock(dev)
As shown above, when it is allowed to do async probes, because of
out of memory or work limit, async work is not allowed, to do
sync execute instead. it will lead to A-A deadlock because of
__device_attach_async_helper getting lock dev.
To fix the deadlock, move the async_schedule_dev outside device_lock,
as we can see, in async_schedule_node_domain, the parameter of
queue_work_node is system_unbound_wq, so it can accept concurrent
operations. which will also not change the code logic, and will
not lead to deadlock.
In the Linux kernel, the following vulnerability has been resolved:
firmware: dmi-sysfs: Fix memory leak in dmi_sysfs_register_handle
kobject_init_and_add() takes reference even when it fails.
According to the doc of kobject_init_and_add()
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object.
Fix this issue by calling kobject_put().
In the Linux kernel, the following vulnerability has been resolved:
amt: fix possible memory leak in amt_rcv()
If an amt receives packets and it finds socket.
If it can't find a socket, it should free a received skb.
But it doesn't.
So, a memory leak would possibly occur.
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: mv88e6xxx: Fix refcount leak in mv88e6xxx_mdios_register
of_get_child_by_name() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
mv88e6xxx_mdio_register() pass the device node to of_mdiobus_register().
We don't need the device node after it.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix reference count leak in smb_check_perm_dacl()
The issue happens in a specific path in smb_check_perm_dacl(). When
"id" and "uid" have the same value, the function simply jumps out of
the loop without decrementing the reference count of the object
"posix_acls", which is increased by get_acl() earlier. This may
result in memory leaks.
Fix it by decreasing the reference count of "posix_acls" before
jumping to label "check_access_bits".
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Off by one in dm_dmub_outbox1_low_irq()
The > ARRAY_SIZE() should be >= ARRAY_SIZE() to prevent an out of bounds
access.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to clear dirty inode in f2fs_evict_inode()
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215904
The kernel message is shown below:
kernel BUG at fs/f2fs/inode.c:825!
Call Trace:
evict+0x282/0x4e0
__dentry_kill+0x2b2/0x4d0
shrink_dentry_list+0x17c/0x4f0
shrink_dcache_parent+0x143/0x1e0
do_one_tree+0x9/0x30
shrink_dcache_for_umount+0x51/0x120
generic_shutdown_super+0x5c/0x3a0
kill_block_super+0x90/0xd0
kill_f2fs_super+0x225/0x310
deactivate_locked_super+0x78/0xc0
cleanup_mnt+0x2b7/0x480
task_work_run+0xc8/0x150
exit_to_user_mode_prepare+0x14a/0x150
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x48/0x90
The root cause is: inode node and dnode node share the same nid,
so during f2fs_evict_inode(), dnode node truncation will invalidate
its NAT entry, so when truncating inode node, it fails due to
invalid NAT entry, result in inode is still marked as dirty, fix
this issue by clearing dirty for inode and setting SBI_NEED_FSCK
flag in filesystem.
output from dump.f2fs:
[print_node_info: 354] Node ID [0xf:15] is inode
i_nid[0] [0x f : 15]
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on block address in f2fs_do_zero_range()
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215894
I have encountered a bug in F2FS file system in kernel v5.17.
I have uploaded the system call sequence as case.c, and a fuzzed image can
be found in google net disk
The kernel should enable CONFIG_KASAN=y and CONFIG_KASAN_INLINE=y. You can
reproduce the bug by running the following commands:
kernel BUG at fs/f2fs/segment.c:2291!
Call Trace:
f2fs_invalidate_blocks+0x193/0x2d0
f2fs_fallocate+0x2593/0x4a70
vfs_fallocate+0x2a5/0xac0
ksys_fallocate+0x35/0x70
__x64_sys_fallocate+0x8e/0xf0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is, after image was fuzzed, block mapping info in inode
will be inconsistent with SIT table, so in f2fs_fallocate(), it will cause
panic when updating SIT with invalid blkaddr.
Let's fix the issue by adding sanity check on block address before updating
SIT table with it.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check for inline inode
Yanming reported a kernel bug in Bugzilla kernel [1], which can be
reproduced. The bug message is:
The kernel message is shown below:
kernel BUG at fs/inode.c:611!
Call Trace:
evict+0x282/0x4e0
__dentry_kill+0x2b2/0x4d0
dput+0x2dd/0x720
do_renameat2+0x596/0x970
__x64_sys_rename+0x78/0x90
do_syscall_64+0x3b/0x90
[1] https://bugzilla.kernel.org/show_bug.cgi?id=215895
The bug is due to fuzzed inode has both inline_data and encrypted flags.
During f2fs_evict_inode(), as the inode was deleted by rename(), it
will cause inline data conversion due to conflicting flags. The page
cache will be polluted and the panic will be triggered in clear_inode().
Try fixing the bug by doing more sanity checks for inline data inode in
sanity_check_inode().
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on total_data_blocks
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215916
The kernel message is shown below:
kernel BUG at fs/f2fs/segment.c:2560!
Call Trace:
allocate_segment_by_default+0x228/0x440
f2fs_allocate_data_block+0x13d1/0x31f0
do_write_page+0x18d/0x710
f2fs_outplace_write_data+0x151/0x250
f2fs_do_write_data_page+0xef9/0x1980
move_data_page+0x6af/0xbc0
do_garbage_collect+0x312f/0x46f0
f2fs_gc+0x6b0/0x3bc0
f2fs_balance_fs+0x921/0x2260
f2fs_write_single_data_page+0x16be/0x2370
f2fs_write_cache_pages+0x428/0xd00
f2fs_write_data_pages+0x96e/0xd50
do_writepages+0x168/0x550
__writeback_single_inode+0x9f/0x870
writeback_sb_inodes+0x47d/0xb20
__writeback_inodes_wb+0xb2/0x200
wb_writeback+0x4bd/0x660
wb_workfn+0x5f3/0xab0
process_one_work+0x79f/0x13e0
worker_thread+0x89/0xf60
kthread+0x26a/0x300
ret_from_fork+0x22/0x30
RIP: 0010:new_curseg+0xe8d/0x15f0
The root cause is: ckpt.valid_block_count is inconsistent with SIT table,
stat info indicates filesystem has free blocks, but SIT table indicates
filesystem has no free segment.
So that during garbage colloection, it triggers panic when LFS allocator
fails to find free segment.
This patch tries to fix this issue by checking consistency in between
ckpt.valid_block_count and block accounted from SIT.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: memleak flow rule from commit path
Abort path release flow rule object, however, commit path does not.
Update code to destroy these objects before releasing the transaction.
In the Linux kernel, the following vulnerability has been resolved:
efi: Do not import certificates from UEFI Secure Boot for T2 Macs
On Apple T2 Macs, when Linux attempts to read the db and dbx efi variables
at early boot to load UEFI Secure Boot certificates, a page fault occurs
in Apple firmware code and EFI runtime services are disabled with the
following logs:
[Firmware Bug]: Page fault caused by firmware at PA: 0xffffb1edc0068000
WARNING: CPU: 3 PID: 104 at arch/x86/platform/efi/quirks.c:735 efi_crash_gracefully_on_page_fault+0x50/0xf0
(Removed some logs from here)
Call Trace:
<TASK>
page_fault_oops+0x4f/0x2c0
? search_bpf_extables+0x6b/0x80
? search_module_extables+0x50/0x80
? search_exception_tables+0x5b/0x60
kernelmode_fixup_or_oops+0x9e/0x110
__bad_area_nosemaphore+0x155/0x190
bad_area_nosemaphore+0x16/0x20
do_kern_addr_fault+0x8c/0xa0
exc_page_fault+0xd8/0x180
asm_exc_page_fault+0x1e/0x30
(Removed some logs from here)
? __efi_call+0x28/0x30
? switch_mm+0x20/0x30
? efi_call_rts+0x19a/0x8e0
? process_one_work+0x222/0x3f0
? worker_thread+0x4a/0x3d0
? kthread+0x17a/0x1a0
? process_one_work+0x3f0/0x3f0
? set_kthread_struct+0x40/0x40
? ret_from_fork+0x22/0x30
</TASK>
---[ end trace 1f82023595a5927f ]---
efi: Froze efi_rts_wq and disabled EFI Runtime Services
integrity: Couldn't get size: 0x8000000000000015
integrity: MODSIGN: Couldn't get UEFI db list
efi: EFI Runtime Services are disabled!
integrity: Couldn't get size: 0x8000000000000015
integrity: Couldn't get UEFI dbx list
integrity: Couldn't get size: 0x8000000000000015
integrity: Couldn't get mokx list
integrity: Couldn't get size: 0x80000000
So we avoid reading these UEFI variables and thus prevent the crash.
In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: Trap RDMA segment overflows
Prevent svc_rdma_build_writes() from walking off the end of a Write
chunk's segment array. Caught with KASAN.
The test that this fix replaces is invalid, and might have been left
over from an earlier prototype of the PCL work.
In the Linux kernel, the following vulnerability has been resolved:
ata: pata_octeon_cf: Fix refcount leak in octeon_cf_probe
of_find_device_by_node() takes reference, we should use put_device()
to release it when not need anymore.
Add missing put_device() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
powerpc/papr_scm: don't requests stats with '0' sized stats buffer
Sachin reported [1] that on a POWER-10 lpar he is seeing a kernel panic being
reported with vPMEM when papr_scm probe is being called. The panic is of the
form below and is observed only with following option disabled(profile) for the
said LPAR 'Enable Performance Information Collection' in the HMC:
Kernel attempted to write user page (1c) - exploit attempt? (uid: 0)
BUG: Kernel NULL pointer dereference on write at 0x0000001c
Faulting instruction address: 0xc008000001b90844
Oops: Kernel access of bad area, sig: 11 [#1]
<snip>
NIP [c008000001b90844] drc_pmem_query_stats+0x5c/0x270 [papr_scm]
LR [c008000001b92794] papr_scm_probe+0x2ac/0x6ec [papr_scm]
Call Trace:
0xc00000000941bca0 (unreliable)
papr_scm_probe+0x2ac/0x6ec [papr_scm]
platform_probe+0x98/0x150
really_probe+0xfc/0x510
__driver_probe_device+0x17c/0x230
<snip>
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Fatal exception
On investigation looks like this panic was caused due to a 'stat_buffer' of
size==0 being provided to drc_pmem_query_stats() to fetch all performance
stats-ids of an NVDIMM. However drc_pmem_query_stats() shouldn't have been called
since the vPMEM NVDIMM doesn't support and performance stat-id's. This was caused
due to missing check for 'p->stat_buffer_len' at the beginning of
papr_scm_pmu_check_events() which indicates that the NVDIMM doesn't support
performance-stats.
Fix this by introducing the check for 'p->stat_buffer_len' at the beginning of
papr_scm_pmu_check_events().
[1] https://lore.kernel.org/all/6B3A522A-6A5F-4CC9-B268-0C63AA6E07D3@linux.ibm.com
In the Linux kernel, the following vulnerability has been resolved:
net: altera: Fix refcount leak in altera_tse_mdio_create
Every iteration of for_each_child_of_node() decrements
the reference count of the previous node.
When break from a for_each_child_of_node() loop,
we need to explicitly call of_node_put() on the child node when
not need anymore.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
ext4: filter out EXT4_FC_REPLAY from on-disk superblock field s_state
The EXT4_FC_REPLAY bit in sbi->s_mount_state is used to indicate that
we are in the middle of replay the fast commit journal. This was
actually a mistake, since the sbi->s_mount_info is initialized from
es->s_state. Arguably s_mount_state is misleadingly named, but the
name is historical --- s_mount_state and s_state dates back to ext2.
What should have been used is the ext4_{set,clear,test}_mount_flag()
inline functions, which sets EXT4_MF_* bits in sbi->s_mount_flags.
The problem with using EXT4_FC_REPLAY is that a maliciously corrupted
superblock could result in EXT4_FC_REPLAY getting set in
s_mount_state. This bypasses some sanity checks, and this can trigger
a BUG() in ext4_es_cache_extent(). As a easy-to-backport-fix, filter
out the EXT4_FC_REPLAY bit for now. We should eventually transition
away from EXT4_FC_REPLAY to something like EXT4_MF_REPLAY.
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: lantiq_gswip: Fix refcount leak in gswip_gphy_fw_list
Every iteration of for_each_available_child_of_node() decrements
the reference count of the previous node.
when breaking early from a for_each_available_child_of_node() loop,
we need to explicitly call of_node_put() on the gphy_fw_np.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Fix a data-race in unix_dgram_peer_wake_me().
unix_dgram_poll() calls unix_dgram_peer_wake_me() without `other`'s
lock held and check if its receive queue is full. Here we need to
use unix_recvq_full_lockless() instead of unix_recvq_full(), otherwise
KCSAN will report a data-race.
In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid cycles in directory h-tree
A maliciously corrupted filesystem can contain cycles in the h-tree
stored inside a directory. That can easily lead to the kernel corrupting
tree nodes that were already verified under its hands while doing a node
split and consequently accessing unallocated memory. Fix the problem by
verifying traversed block numbers are unique.