High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: avoid possible UaF when selecting endp
select_local_address() and select_signal_address() both select an
endpoint entry from the list inside an RCU protected section, but return
a reference to it, to be read later on. If the entry is dereferenced
after the RCU unlock, reading info could cause a Use-after-Free.
A simple solution is to copy the required info while inside the RCU
protected section to avoid any risk of UaF later. The address ID might
need to be modified later to handle the ID0 case later, so a copy seems
OK to deal with.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 8.1
In the Linux kernel, the following vulnerability has been resolved:
mm, slub: do not call do_slab_free for kfence object
In 782f8906f805 the freeing of kfence objects was moved from deep
inside do_slab_free to the wrapper functions outside. This is a nice
change, but unfortunately it missed one spot in __kmem_cache_free_bulk.
This results in a crash like this:
BUG skbuff_head_cache (Tainted: G S B E ): Padding overwritten. 0xffff88907fea0f00-0xffff88907fea0fff @offset=3840
slab_err (mm/slub.c:1129)
free_to_partial_list (mm/slub.c:? mm/slub.c:4036)
slab_pad_check (mm/slub.c:864 mm/slub.c:1290)
check_slab (mm/slub.c:?)
free_to_partial_list (mm/slub.c:3171 mm/slub.c:4036)
kmem_cache_alloc_bulk (mm/slub.c:? mm/slub.c:4495 mm/slub.c:4586 mm/slub.c:4635)
napi_build_skb (net/core/skbuff.c:348 net/core/skbuff.c:527 net/core/skbuff.c:549)
All the other callers to do_slab_free appear to be ok.
Add a kfence_free check in __kmem_cache_free_bulk to avoid the crash.
Published Sep 4, 2024 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: SHAMPO, Fix invalid WQ linked list unlink
When all the strides in a WQE have been consumed, the WQE is unlinked
from the WQ linked list (mlx5_wq_ll_pop()). For SHAMPO, it is possible
to receive CQEs with 0 consumed strides for the same WQE even after the
WQE is fully consumed and unlinked. This triggers an additional unlink
for the same wqe which corrupts the linked list.
Fix this scenario by accepting 0 sized consumed strides without
unlinking the WQE again.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
drm/mgag200: Bind I2C lifetime to DRM device
Managed cleanup with devm_add_action_or_reset() will release the I2C
adapter when the underlying Linux device goes away. But the connector
still refers to it, so this cleanup leaves behind a stale pointer
in struct drm_connector.ddc.
Bind the lifetime of the I2C adapter to the connector's lifetime by
using DRM's managed release. When the DRM device goes away (after
the Linux device) DRM will first clean up the connector and then
clean up the I2C adapter.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
binfmt_flat: Fix corruption when not offsetting data start
Commit 04d82a6d0881 ("binfmt_flat: allow not offsetting data start")
introduced a RISC-V specific variant of the FLAT format which does
not allocate any space for the (obsolete) array of shared library
pointers. However, it did not disable the code which initializes the
array, resulting in the corruption of sizeof(long) bytes before the DATA
segment, generally the end of the TEXT segment.
Introduce MAX_SHARED_LIBS_UPDATE which depends on the state of
CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET to guard the initialization of
the shared library pointer region so that it will only be initialized
if space is reserved for it.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
tracefs: Use generic inode RCU for synchronizing freeing
With structure layout randomization enabled for 'struct inode' we need to
avoid overlapping any of the RCU-used / initialized-only-once members,
e.g. i_lru or i_sb_list to not corrupt related list traversals when making
use of the rcu_head.
For an unlucky structure layout of 'struct inode' we may end up with the
following splat when running the ftrace selftests:
[<...>] list_del corruption, ffff888103ee2cb0->next (tracefs_inode_cache+0x0/0x4e0 [slab object]) is NULL (prev is tracefs_inode_cache+0x78/0x4e0 [slab object])
[<...>] ------------[ cut here ]------------
[<...>] kernel BUG at lib/list_debug.c:54!
[<...>] invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[<...>] CPU: 3 PID: 2550 Comm: mount Tainted: G N 6.8.12-grsec+ #122 ed2f536ca62f28b087b90e3cc906a8d25b3ddc65
[<...>] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[<...>] RIP: 0010:[<ffffffff84656018>] __list_del_entry_valid_or_report+0x138/0x3e0
[<...>] Code: 48 b8 99 fb 65 f2 ff ff ff ff e9 03 5c d9 fc cc 48 b8 99 fb 65 f2 ff ff ff ff e9 33 5a d9 fc cc 48 b8 99 fb 65 f2 ff ff ff ff <0f> 0b 4c 89 e9 48 89 ea 48 89 ee 48 c7 c7 60 8f dd 89 31 c0 e8 2f
[<...>] RSP: 0018:fffffe80416afaf0 EFLAGS: 00010283
[<...>] RAX: 0000000000000098 RBX: ffff888103ee2cb0 RCX: 0000000000000000
[<...>] RDX: ffffffff84655fe8 RSI: ffffffff89dd8b60 RDI: 0000000000000001
[<...>] RBP: ffff888103ee2cb0 R08: 0000000000000001 R09: fffffbd0082d5f25
[<...>] R10: fffffe80416af92f R11: 0000000000000001 R12: fdf99c16731d9b6d
[<...>] R13: 0000000000000000 R14: ffff88819ad4b8b8 R15: 0000000000000000
[<...>] RBX: tracefs_inode_cache+0x0/0x4e0 [slab object]
[<...>] RDX: __list_del_entry_valid_or_report+0x108/0x3e0
[<...>] RSI: __func__.47+0x4340/0x4400
[<...>] RBP: tracefs_inode_cache+0x0/0x4e0 [slab object]
[<...>] RSP: process kstack fffffe80416afaf0+0x7af0/0x8000 [mount 2550 2550]
[<...>] R09: kasan shadow of process kstack fffffe80416af928+0x7928/0x8000 [mount 2550 2550]
[<...>] R10: process kstack fffffe80416af92f+0x792f/0x8000 [mount 2550 2550]
[<...>] R14: tracefs_inode_cache+0x78/0x4e0 [slab object]
[<...>] FS: 00006dcb380c1840(0000) GS:ffff8881e0600000(0000) knlGS:0000000000000000
[<...>] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[<...>] CR2: 000076ab72b30e84 CR3: 000000000b088004 CR4: 0000000000360ef0 shadow CR4: 0000000000360ef0
[<...>] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[<...>] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[<...>] ASID: 0003
[<...>] Stack:
[<...>] ffffffff818a2315 00000000f5c856ee ffffffff896f1840 ffff888103ee2cb0
[<...>] ffff88812b6b9750 0000000079d714b6 fffffbfff1e9280b ffffffff8f49405f
[<...>] 0000000000000001 0000000000000000 ffff888104457280 ffffffff8248b392
[<...>] Call Trace:
[<...>] <TASK>
[<...>] [<ffffffff818a2315>] ? lock_release+0x175/0x380 fffffe80416afaf0
[<...>] [<ffffffff8248b392>] list_lru_del+0x152/0x740 fffffe80416afb48
[<...>] [<ffffffff8248ba93>] list_lru_del_obj+0x113/0x280 fffffe80416afb88
[<...>] [<ffffffff8940fd19>] ? _atomic_dec_and_lock+0x119/0x200 fffffe80416afb90
[<...>] [<ffffffff8295b244>] iput_final+0x1c4/0x9a0 fffffe80416afbb8
[<...>] [<ffffffff8293a52b>] dentry_unlink_inode+0x44b/0xaa0 fffffe80416afbf8
[<...>] [<ffffffff8293fefc>] __dentry_kill+0x23c/0xf00 fffffe80416afc40
[<...>] [<ffffffff8953a85f>] ? __this_cpu_preempt_check+0x1f/0xa0 fffffe80416afc48
[<...>] [<ffffffff82949ce5>] ? shrink_dentry_list+0x1c5/0x760 fffffe80416afc70
[<...>] [<ffffffff82949b71>] ? shrink_dentry_list+0x51/0x760 fffffe80416afc78
[<...>] [<ffffffff82949da8>] shrink_dentry_list+0x288/0x760 fffffe80416afc80
[<...>] [<ffffffff8294ae75>] shrink_dcache_sb+0x155/0x420 fffffe80416afcc8
[<...>] [<ffffffff8953a7c3>] ? debug_smp_processor_id+0x23/0xa0 fffffe80416afce0
[<...>] [<ffffffff8294ad20>] ? do_one_tre
---truncated---
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
ALSA: line6: Fix racy access to midibuf
There can be concurrent accesses to line6 midibuf from both the URB
completion callback and the rawmidi API access. This could be a cause
of KMSAN warning triggered by syzkaller below (so put as reported-by
here).
This patch protects the midibuf call of the former code path with a
spinlock for avoiding the possible races.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
serial: sc16is7xx: fix TX fifo corruption
Sometimes, when a packet is received on channel A at almost the same time
as a packet is about to be transmitted on channel B, we observe with a
logic analyzer that the received packet on channel A is transmitted on
channel B. In other words, the Tx buffer data on channel B is corrupted
with data from channel A.
The problem appeared since commit 4409df5866b7 ("serial: sc16is7xx: change
EFR lock to operate on each channels"), which changed the EFR locking to
operate on each channel instead of chip-wise.
This commit has introduced a regression, because the EFR lock is used not
only to protect the EFR registers access, but also, in a very obscure and
undocumented way, to protect access to the data buffer, which is shared by
the Tx and Rx handlers, but also by each channel of the IC.
Fix this regression first by switching to kfifo_out_linear_ptr() in
sc16is7xx_handle_tx() to eliminate the need for a shared Rx/Tx buffer.
Secondly, replace the chip-wise Rx buffer with a separate Rx buffer for
each channel.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.1
In the Linux kernel, the following vulnerability has been resolved:
serial: sc16is7xx: fix invalid FIFO access with special register set
When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.
Call graph example:
sc16is7xx_startup(): entry
sc16is7xx_ms_proc(): entry
sc16is7xx_set_termios(): entry
sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
sc16is7xx_port_irq() entry --> IIR is 0x0C
sc16is7xx_handle_rx() entry
sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
mapped to DLL (LCR=LCR_CONF_MODE_A)
sc16is7xx_set_baud(): exit --> Restore access to general register set
Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
parisc: fix a possible DMA corruption
ARCH_DMA_MINALIGN was defined as 16 - this is too small - it may be
possible that two unrelated 16-byte allocations share a cache line. If
one of these allocations is written using DMA and the other is written
using cached write, the value that was written with DMA may be
corrupted.
This commit changes ARCH_DMA_MINALIGN to be 128 on PA20 and 32 on PA1.1 -
that's the largest possible cache line size.
As different parisc microarchitectures have different cache line size, we
define arch_slab_minalign(), cache_line_size() and
dma_get_cache_alignment() so that the kernel may tune slab cache
parameters dynamically, based on the detected cache line size.
Published Sep 4, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
kcm: Serialise kcm_sendmsg() for the same socket.
syzkaller reported UAF in kcm_release(). [0]
The scenario is
1. Thread A builds a skb with MSG_MORE and sets kcm->seq_skb.
2. Thread A resumes building skb from kcm->seq_skb but is blocked
by sk_stream_wait_memory()
3. Thread B calls sendmsg() concurrently, finishes building kcm->seq_skb
and puts the skb to the write queue
4. Thread A faces an error and finally frees skb that is already in the
write queue
5. kcm_release() does double-free the skb in the write queue
When a thread is building a MSG_MORE skb, another thread must not touch it.
Let's add a per-sk mutex and serialise kcm_sendmsg().
[0]:
BUG: KASAN: slab-use-after-free in __skb_unlink include/linux/skbuff.h:2366 [inline]
BUG: KASAN: slab-use-after-free in __skb_dequeue include/linux/skbuff.h:2385 [inline]
BUG: KASAN: slab-use-after-free in __skb_queue_purge_reason include/linux/skbuff.h:3175 [inline]
BUG: KASAN: slab-use-after-free in __skb_queue_purge include/linux/skbuff.h:3181 [inline]
BUG: KASAN: slab-use-after-free in kcm_release+0x170/0x4c8 net/kcm/kcmsock.c:1691
Read of size 8 at addr ffff0000ced0fc80 by task syz-executor329/6167
CPU: 1 PID: 6167 Comm: syz-executor329 Tainted: G B 6.8.0-rc5-syzkaller-g9abbc24128bc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call trace:
dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x178/0x518 mm/kasan/report.c:488
kasan_report+0xd8/0x138 mm/kasan/report.c:601
__asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381
__skb_unlink include/linux/skbuff.h:2366 [inline]
__skb_dequeue include/linux/skbuff.h:2385 [inline]
__skb_queue_purge_reason include/linux/skbuff.h:3175 [inline]
__skb_queue_purge include/linux/skbuff.h:3181 [inline]
kcm_release+0x170/0x4c8 net/kcm/kcmsock.c:1691
__sock_release net/socket.c:659 [inline]
sock_close+0xa4/0x1e8 net/socket.c:1421
__fput+0x30c/0x738 fs/file_table.c:376
____fput+0x20/0x30 fs/file_table.c:404
task_work_run+0x230/0x2e0 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0x618/0x1f64 kernel/exit.c:871
do_group_exit+0x194/0x22c kernel/exit.c:1020
get_signal+0x1500/0x15ec kernel/signal.c:2893
do_signal+0x23c/0x3b44 arch/arm64/kernel/signal.c:1249
do_notify_resume+0x74/0x1f4 arch/arm64/kernel/entry-common.c:148
exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:713
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
Allocated by task 6166:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x40/0x78 mm/kasan/common.c:68
kasan_save_alloc_info+0x70/0x84 mm/kasan/generic.c:626
unpoison_slab_object mm/kasan/common.c:314 [inline]
__kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:340
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook mm/slub.c:3813 [inline]
slab_alloc_node mm/slub.c:3860 [inline]
kmem_cache_alloc_node+0x204/0x4c0 mm/slub.c:3903
__alloc_skb+0x19c/0x3d8 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1296 [inline]
kcm_sendmsg+0x1d3c/0x2124 net/kcm/kcmsock.c:783
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
sock_sendmsg+0x220/0x2c0 net/socket.c:768
splice_to_socket+0x7cc/0xd58 fs/splice.c:889
do_splice_from fs/splice.c:941 [inline]
direct_splice_actor+0xec/0x1d8 fs/splice.c:1164
splice_direct_to_actor+0x438/0xa0c fs/splice.c:1108
do_splice_direct_actor
---truncated---
Published Aug 31, 2024 · Updated Aug 5, 2026
High · CVSS 7.1
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nfnetlink: Initialise extack before use in ACKs
Add missing extack initialisation when ACKing BATCH_BEGIN and BATCH_END.
Published Aug 31, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on F2FS_INLINE_DATA flag in inode during GC
syzbot reports a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/inline.c:258!
CPU: 1 PID: 34 Comm: kworker/u8:2 Not tainted 6.9.0-rc6-syzkaller-00012-g9e4bc4bcae01 #0
RIP: 0010:f2fs_write_inline_data+0x781/0x790 fs/f2fs/inline.c:258
Call Trace:
f2fs_write_single_data_page+0xb65/0x1d60 fs/f2fs/data.c:2834
f2fs_write_cache_pages fs/f2fs/data.c:3133 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3288 [inline]
f2fs_write_data_pages+0x1efe/0x3a90 fs/f2fs/data.c:3315
do_writepages+0x35b/0x870 mm/page-writeback.c:2612
__writeback_single_inode+0x165/0x10b0 fs/fs-writeback.c:1650
writeback_sb_inodes+0x905/0x1260 fs/fs-writeback.c:1941
wb_writeback+0x457/0xce0 fs/fs-writeback.c:2117
wb_do_writeback fs/fs-writeback.c:2264 [inline]
wb_workfn+0x410/0x1090 fs/fs-writeback.c:2304
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3335
worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
kthread+0x2f2/0x390 kernel/kthread.c:388
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
The root cause is: inline_data inode can be fuzzed, so that there may
be valid blkaddr in its direct node, once f2fs triggers background GC
to migrate the block, it will hit f2fs_bug_on() during dirty page
writeback.
Let's add sanity check on F2FS_INLINE_DATA flag in inode during GC,
so that, it can forbid migrating inline_data inode's data block for
fixing.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to cover read extent cache access with lock
syzbot reports a f2fs bug as below:
BUG: KASAN: slab-use-after-free in sanity_check_extent_cache+0x370/0x410 fs/f2fs/extent_cache.c:46
Read of size 4 at addr ffff8880739ab220 by task syz-executor200/5097
CPU: 0 PID: 5097 Comm: syz-executor200 Not tainted 6.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
sanity_check_extent_cache+0x370/0x410 fs/f2fs/extent_cache.c:46
do_read_inode fs/f2fs/inode.c:509 [inline]
f2fs_iget+0x33e1/0x46e0 fs/f2fs/inode.c:560
f2fs_nfs_get_inode+0x74/0x100 fs/f2fs/super.c:3237
generic_fh_to_dentry+0x9f/0xf0 fs/libfs.c:1413
exportfs_decode_fh_raw+0x152/0x5f0 fs/exportfs/expfs.c:444
exportfs_decode_fh+0x3c/0x80 fs/exportfs/expfs.c:584
do_handle_to_path fs/fhandle.c:155 [inline]
handle_to_path fs/fhandle.c:210 [inline]
do_handle_open+0x495/0x650 fs/fhandle.c:226
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
We missed to cover sanity_check_extent_cache() w/ extent cache lock,
so, below race case may happen, result in use after free issue.
- f2fs_iget
- do_read_inode
- f2fs_init_read_extent_tree
: add largest extent entry in to cache
- shrink
- f2fs_shrink_read_extent_tree
- __shrink_extent_tree
- __detach_extent_node
: drop largest extent entry
- sanity_check_extent_cache
: access et->largest w/o lock
let's refactor sanity_check_extent_cache() to avoid extent cache access
and call it before f2fs_init_read_extent_tree() to fix this issue.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
fou: remove warn in gue_gro_receive on unsupported protocol
Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is
not known or does not have a GRO handler.
Such a packet is easily constructed. Syzbot generates them and sets
off this warning.
Remove the warning as it is expected and not actionable.
The warning was previously reduced from WARN_ON to WARN_ON_ONCE in
commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad
proto callbacks").
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix null ptr deref in dtInsertEntry
[syzbot reported]
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 5061 Comm: syz-executor404 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:dtInsertEntry+0xd0c/0x1780 fs/jfs/jfs_dtree.c:3713
...
[Analyze]
In dtInsertEntry(), when the pointer h has the same value as p, after writing
name in UniStrncpy_to_le(), p->header.flag will be cleared. This will cause the
previously true judgment "p->header.flag & BT-LEAF" to change to no after writing
the name operation, this leads to entering an incorrect branch and accessing the
uninitialized object ih when judging this condition for the second time.
[Fix]
After got the page, check freelist first, if freelist == 0 then exit dtInsert()
and return -EINVAL.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: mcast: wait for previous gc cycles when removing port
syzbot hit a use-after-free[1] which is caused because the bridge doesn't
make sure that all previous garbage has been collected when removing a
port. What happens is:
CPU 1 CPU 2
start gc cycle remove port
acquire gc lock first
wait for lock
call br_multicasg_gc() directly
acquire lock now but free port
the port can be freed
while grp timers still
running
Make sure all previous gc cycles have finished by using flush_work before
freeing the port.
[1]
BUG: KASAN: slab-use-after-free in br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861
Read of size 8 at addr ffff888071d6d000 by task syz.5.1232/9699
CPU: 1 PID: 9699 Comm: syz.5.1232 Not tainted 6.10.0-rc5-syzkaller-00021-g24ca36a562d6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861
call_timer_fn+0x1a3/0x610 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers+0x74b/0xaf0 kernel/time/timer.c:2417
__run_timer_base kernel/time/timer.c:2428 [inline]
__run_timer_base kernel/time/timer.c:2421 [inline]
run_timer_base+0x111/0x190 kernel/time/timer.c:2437
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.3
In the Linux kernel, the following vulnerability has been resolved:
bnxt_en : Fix memory out-of-bounds in bnxt_fill_hw_rss_tbl()
A recent commit has modified the code in __bnxt_reserve_rings() to
set the default RSS indirection table to default only when the number
of RX rings is changing. While this works for newer firmware that
requires RX ring reservations, it causes the regression on older
firmware not requiring RX ring resrvations (BNXT_NEW_RM() returns
false).
With older firmware, RX ring reservations are not required and so
hw_resc->resv_rx_rings is not always set to the proper value. The
comparison:
if (old_rx_rings != bp->hw_resc.resv_rx_rings)
in __bnxt_reserve_rings() may be false even when the RX rings are
changing. This will cause __bnxt_reserve_rings() to skip setting
the default RSS indirection table to default to match the current
number of RX rings. This may later cause bnxt_fill_hw_rss_tbl() to
use an out-of-range index.
We already have bnxt_check_rss_tbl_no_rmgr() to handle exactly this
scenario. We just need to move it up in bnxt_need_reserve_rings()
to be called unconditionally when using older firmware. Without the
fix, if the TX rings are changing, we'll skip the
bnxt_check_rss_tbl_no_rmgr() call and __bnxt_reserve_rings() may also
skip the bnxt_set_dflt_rss_indir_tbl() call for the reason explained
in the last paragraph. Without setting the default RSS indirection
table to default, it causes the regression:
BUG: KASAN: slab-out-of-bounds in __bnxt_hwrm_vnic_set_rss+0xb79/0xe40
Read of size 2 at addr ffff8881c5809618 by task ethtool/31525
Call Trace:
__bnxt_hwrm_vnic_set_rss+0xb79/0xe40
bnxt_hwrm_vnic_rss_cfg_p5+0xf7/0x460
__bnxt_setup_vnic_p5+0x12e/0x270
__bnxt_open_nic+0x2262/0x2f30
bnxt_open_nic+0x5d/0xf0
ethnl_set_channels+0x5d4/0xb30
ethnl_default_set_doit+0x2f1/0x620
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7
In the Linux kernel, the following vulnerability has been resolved:
nvme: apple: fix device reference counting
Drivers must call nvme_uninit_ctrl after a successful nvme_init_ctrl.
Split the allocation side out to make the error handling boundary easier
to navigate. The apple driver had been doing this wrong, leaking the
controller device memory on a tagset failure.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
bpf: add missing check_func_arg_reg_off() to prevent out-of-bounds memory accesses
Currently, it's possible to pass in a modified CONST_PTR_TO_DYNPTR to
a global function as an argument. The adverse effects of this is that
BPF helpers can continue to make use of this modified
CONST_PTR_TO_DYNPTR from within the context of the global function,
which can unintentionally result in out-of-bounds memory accesses and
therefore compromise overall system stability i.e.
[ 244.157771] BUG: KASAN: slab-out-of-bounds in bpf_dynptr_data+0x137/0x140
[ 244.161345] Read of size 8 at addr ffff88810914be68 by task test_progs/302
[ 244.167151] CPU: 0 PID: 302 Comm: test_progs Tainted: G O E 6.10.0-rc3-00131-g66b586715063 #533
[ 244.174318] Call Trace:
[ 244.175787] <TASK>
[ 244.177356] dump_stack_lvl+0x66/0xa0
[ 244.179531] print_report+0xce/0x670
[ 244.182314] ? __virt_addr_valid+0x200/0x3e0
[ 244.184908] kasan_report+0xd7/0x110
[ 244.187408] ? bpf_dynptr_data+0x137/0x140
[ 244.189714] ? bpf_dynptr_data+0x137/0x140
[ 244.192020] bpf_dynptr_data+0x137/0x140
[ 244.194264] bpf_prog_b02a02fdd2bdc5fa_global_call_bpf_dynptr_data+0x22/0x26
[ 244.198044] bpf_prog_b0fe7b9d7dc3abde_callback_adjust_bpf_dynptr_reg_off+0x1f/0x23
[ 244.202136] bpf_user_ringbuf_drain+0x2c7/0x570
[ 244.204744] ? 0xffffffffc0009e58
[ 244.206593] ? __pfx_bpf_user_ringbuf_drain+0x10/0x10
[ 244.209795] bpf_prog_33ab33f6a804ba2d_user_ringbuf_callback_const_ptr_to_dynptr_reg_off+0x47/0x4b
[ 244.215922] bpf_trampoline_6442502480+0x43/0xe3
[ 244.218691] __x64_sys_prlimit64+0x9/0xf0
[ 244.220912] do_syscall_64+0xc1/0x1d0
[ 244.223043] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 244.226458] RIP: 0033:0x7ffa3eb8f059
[ 244.228582] Code: 08 89 e8 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8f 1d 0d 00 f7 d8 64 89 01 48
[ 244.241307] RSP: 002b:00007ffa3e9c6eb8 EFLAGS: 00000206 ORIG_RAX: 000000000000012e
[ 244.246474] RAX: ffffffffffffffda RBX: 00007ffa3e9c7cdc RCX: 00007ffa3eb8f059
[ 244.250478] RDX: 00007ffa3eb162b4 RSI: 0000000000000000 RDI: 00007ffa3e9c7fb0
[ 244.255396] RBP: 00007ffa3e9c6ed0 R08: 00007ffa3e9c76c0 R09: 0000000000000000
[ 244.260195] R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffff80
[ 244.264201] R13: 000000000000001c R14: 00007ffc5d6b4260 R15: 00007ffa3e1c7000
[ 244.268303] </TASK>
Add a check_func_arg_reg_off() to the path in which the BPF verifier
verifies the arguments of global function arguments, specifically
those which take an argument of type ARG_PTR_TO_DYNPTR |
MEM_RDONLY. Also, process_dynptr_func() doesn't appear to perform any
explicit and strict type matching on the supplied register type, so
let's also enforce that a register either type PTR_TO_STACK or
CONST_PTR_TO_DYNPTR is by the caller.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
net: drop bad gso csum_start and offset in virtio_net_hdr
Tighten csum_start and csum_offset checks in virtio_net_hdr_to_skb
for GSO packets.
The function already checks that a checksum requested with
VIRTIO_NET_HDR_F_NEEDS_CSUM is in skb linear. But for GSO packets
this might not hold for segs after segmentation.
Syzkaller demonstrated to reach this warning in skb_checksum_help
offset = skb_checksum_start_offset(skb);
ret = -EINVAL;
if (WARN_ON_ONCE(offset >= skb_headlen(skb)))
By injecting a TSO packet:
WARNING: CPU: 1 PID: 3539 at net/core/dev.c:3284 skb_checksum_help+0x3d0/0x5b0
ip_do_fragment+0x209/0x1b20 net/ipv4/ip_output.c:774
ip_finish_output_gso net/ipv4/ip_output.c:279 [inline]
__ip_finish_output+0x2bd/0x4b0 net/ipv4/ip_output.c:301
iptunnel_xmit+0x50c/0x930 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x2296/0x2c70 net/ipv4/ip_tunnel.c:813
__gre_xmit net/ipv4/ip_gre.c:469 [inline]
ipgre_xmit+0x759/0xa60 net/ipv4/ip_gre.c:661
__netdev_start_xmit include/linux/netdevice.h:4850 [inline]
netdev_start_xmit include/linux/netdevice.h:4864 [inline]
xmit_one net/core/dev.c:3595 [inline]
dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3611
__dev_queue_xmit+0x1b97/0x3c90 net/core/dev.c:4261
packet_snd net/packet/af_packet.c:3073 [inline]
The geometry of the bad input packet at tcp_gso_segment:
[ 52.003050][ T8403] skb len=12202 headroom=244 headlen=12093 tailroom=0
[ 52.003050][ T8403] mac=(168,24) mac_len=24 net=(192,52) trans=244
[ 52.003050][ T8403] shinfo(txflags=0 nr_frags=1 gso(size=1552 type=3 segs=0))
[ 52.003050][ T8403] csum(0x60000c7 start=199 offset=1536
ip_summed=3 complete_sw=0 valid=0 level=0)
Mitigate with stricter input validation.
csum_offset: for GSO packets, deduce the correct value from gso_type.
This is already done for USO. Extend it to TSO. Let UFO be:
udp[46]_ufo_fragment ignores these fields and always computes the
checksum in software.
csum_start: finding the real offset requires parsing to the transport
header. Do not add a parser, use existing segmentation parsing. Thanks
to SKB_GSO_DODGY, that also catches bad packets that are hw offloaded.
Again test both TSO and USO. Do not test UFO for the above reason, and
do not test UDP tunnel offload.
GSO packet are almost always CHECKSUM_PARTIAL. USO packets may be
CHECKSUM_NONE since commit 10154dbded6d6 ("udp: Allow GSO transmit
from devices with no checksum offload"), but then still these fields
are initialized correctly in udp4_hwcsum/udp6_hwcsum_outgoing. So no
need to test for ip_summed == CHECKSUM_PARTIAL first.
This revises an existing fix mentioned in the Fixes tag, which broke
small packets with GSO offload, as detected by kselftests.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
memcg: protect concurrent access to mem_cgroup_idr
Commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after
many small jobs") decoupled the memcg IDs from the CSS ID space to fix the
cgroup creation failures. It introduced IDR to maintain the memcg ID
space. The IDR depends on external synchronization mechanisms for
modifications. For the mem_cgroup_idr, the idr_alloc() and idr_replace()
happen within css callback and thus are protected through cgroup_mutex
from concurrent modifications. However idr_remove() for mem_cgroup_idr
was not protected against concurrency and can be run concurrently for
different memcgs when they hit their refcnt to zero. Fix that.
We have been seeing list_lru based kernel crashes at a low frequency in
our fleet for a long time. These crashes were in different part of
list_lru code including list_lru_add(), list_lru_del() and reparenting
code. Upon further inspection, it looked like for a given object (dentry
and inode), the super_block's list_lru didn't have list_lru_one for the
memcg of that object. The initial suspicions were either the object is
not allocated through kmem_cache_alloc_lru() or somehow
memcg_list_lru_alloc() failed to allocate list_lru_one() for a memcg but
returned success. No evidence were found for these cases.
Looking more deeply, we started seeing situations where valid memcg's id
is not present in mem_cgroup_idr and in some cases multiple valid memcgs
have same id and mem_cgroup_idr is pointing to one of them. So, the most
reasonable explanation is that these situations can happen due to race
between multiple idr_remove() calls or race between
idr_alloc()/idr_replace() and idr_remove(). These races are causing
multiple memcgs to acquire the same ID and then offlining of one of them
would cleanup list_lrus on the system for all of them. Later access from
other memcgs to the list_lru cause crashes due to missing list_lru_one.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
tracing: Have format file honor EVENT_FILE_FL_FREED
When eventfs was introduced, special care had to be done to coordinate the
freeing of the file meta data with the files that are exposed to user
space. The file meta data would have a ref count that is set when the file
is created and would be decremented and freed after the last user that
opened the file closed it. When the file meta data was to be freed, it
would set a flag (EVENT_FILE_FL_FREED) to denote that the file is freed,
and any new references made (like new opens or reads) would fail as it is
marked freed. This allowed other meta data to be freed after this flag was
set (under the event_mutex).
All the files that were dynamically created in the events directory had a
pointer to the file meta data and would call event_release() when the last
reference to the user space file was closed. This would be the time that it
is safe to free the file meta data.
A shortcut was made for the "format" file. It's i_private would point to
the "call" entry directly and not point to the file's meta data. This is
because all format files are the same for the same "call", so it was
thought there was no reason to differentiate them. The other files
maintain state (like the "enable", "trigger", etc). But this meant if the
file were to disappear, the "format" file would be unaware of it.
This caused a race that could be trigger via the user_events test (that
would create dynamic events and free them), and running a loop that would
read the user_events format files:
In one console run:
# cd tools/testing/selftests/user_events
# while true; do ./ftrace_test; done
And in another console run:
# cd /sys/kernel/tracing/
# while true; do cat events/user_events/__test_event/format; done 2>/dev/null
With KASAN memory checking, it would trigger a use-after-free bug report
(which was a real bug). This was because the format file was not checking
the file's meta data flag "EVENT_FILE_FL_FREED", so it would access the
event that the file meta data pointed to after the event was freed.
After inspection, there are other locations that were found to not check
the EVENT_FILE_FL_FREED flag when accessing the trace_event_file. Add a
new helper function: event_file_file() that will make sure that the
event_mutex is held, and will return NULL if the trace_event_file has the
EVENT_FILE_FL_FREED flag set. Have the first reference of the struct file
pointer use event_file_file() and check for NULL. Later uses can still use
the event_file_data() helper function if the event_mutex is still held and
was not released since the event_file_file() call.
Published Aug 26, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
mm: list_lru: fix UAF for memory cgroup
The mem_cgroup_from_slab_obj() is supposed to be called under rcu lock or
cgroup_mutex or others which could prevent returned memcg from being
freed. Fix it by adding missing rcu read lock.
Found by code inspection.
[songmuchun@bytedance.com: only grab rcu lock when necessary, per Vlastimil]
Published Aug 26, 2024 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
usb: vhci-hcd: Do not drop references before new references are gained
At a few places the driver carries stale pointers
to references that can still be used. Make sure that does not happen.
This strictly speaking closes ZDI-CAN-22273, though there may be
similar races in the driver.
Published Aug 23, 2024 · Updated Aug 5, 2026
High · CVSS 8.4
In the Linux kernel, the following vulnerability has been resolved:
exec: Fix ToCToU between perm check and set-uid/gid usage
When opening a file for exec via do_filp_open(), permission checking is
done against the file's metadata at that moment, and on success, a file
pointer is passed back. Much later in the execve() code path, the file
metadata (specifically mode, uid, and gid) is used to determine if/how
to set the uid and gid. However, those values may have changed since the
permissions check, meaning the execution may gain unintended privileges.
For example, if a file could change permissions from executable and not
set-id:
---------x 1 root root 16048 Aug 7 13:16 target
to set-id and non-executable:
---S------ 1 root root 16048 Aug 7 13:16 target
it is possible to gain root privileges when execution should have been
disallowed.
While this race condition is rare in real-world scenarios, it has been
observed (and proven exploitable) when package managers are updating
the setuid bits of installed programs. Such files start with being
world-executable but then are adjusted to be group-exec with a set-uid
bit. For example, "chmod o-x,u+s target" makes "target" executable only
by uid "root" and gid "cdrom", while also becoming setuid-root:
-rwxr-xr-x 1 root cdrom 16048 Aug 7 13:16 target
becomes:
-rwsr-xr-- 1 root cdrom 16048 Aug 7 13:16 target
But racing the chmod means users without group "cdrom" membership can
get the permission to execute "target" just before the chmod, and when
the chmod finishes, the exec reaches brpm_fill_uid(), and performs the
setuid to root, violating the expressed authorization of "only cdrom
group members can setuid to root".
Re-check that we still have execute permissions in case the metadata
has changed. It would be better to keep a copy from the perm-check time,
but until we can do that refactoring, the least-bad option is to do a
full inode_permission() call (under inode lock). It is understood that
this is safe against dead-locks, but hardly optimal.
Published Aug 21, 2024 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: change DMA direction while mapping reinjected packets
For fragmented packets, ath12k reassembles each fragment as a normal
packet and then reinjects it into HW ring. In this case, the DMA
direction should be DMA_TO_DEVICE, not DMA_FROM_DEVICE. Otherwise,
an invalid payload may be reinjected into the HW and
subsequently delivered to the host.
Given that arbitrary memory can be allocated to the skb buffer,
knowledge about the data contained in the reinjected buffer is lacking.
Consequently, there’s a risk of private information being leaked.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.1.1-00209-QCAHKSWPL_SILICONZ-1
Published Aug 21, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_acl_erp: Fix object nesting warning
ACLs in Spectrum-2 and newer ASICs can reside in the algorithmic TCAM
(A-TCAM) or in the ordinary circuit TCAM (C-TCAM). The former can
contain more ACLs (i.e., tc filters), but the number of masks in each
region (i.e., tc chain) is limited.
In order to mitigate the effects of the above limitation, the device
allows filters to share a single mask if their masks only differ in up
to 8 consecutive bits. For example, dst_ip/25 can be represented using
dst_ip/24 with a delta of 1 bit. The C-TCAM does not have a limit on the
number of masks being used (and therefore does not support mask
aggregation), but can contain a limited number of filters.
The driver uses the "objagg" library to perform the mask aggregation by
passing it objects that consist of the filter's mask and whether the
filter is to be inserted into the A-TCAM or the C-TCAM since filters in
different TCAMs cannot share a mask.
The set of created objects is dependent on the insertion order of the
filters and is not necessarily optimal. Therefore, the driver will
periodically ask the library to compute a more optimal set ("hints") by
looking at all the existing objects.
When the library asks the driver whether two objects can be aggregated
the driver only compares the provided masks and ignores the A-TCAM /
C-TCAM indication. This is the right thing to do since the goal is to
move as many filters as possible to the A-TCAM. The driver also forbids
two identical masks from being aggregated since this can only happen if
one was intentionally put in the C-TCAM to avoid a conflict in the
A-TCAM.
The above can result in the following set of hints:
H1: {mask X, A-TCAM} -> H2: {mask Y, A-TCAM} // X is Y + delta
H3: {mask Y, C-TCAM} -> H4: {mask Z, A-TCAM} // Y is Z + delta
After getting the hints from the library the driver will start migrating
filters from one region to another while consulting the computed hints
and instructing the device to perform a lookup in both regions during
the transition.
Assuming a filter with mask X is being migrated into the A-TCAM in the
new region, the hints lookup will return H1. Since H2 is the parent of
H1, the library will try to find the object associated with it and
create it if necessary in which case another hints lookup (recursive)
will be performed. This hints lookup for {mask Y, A-TCAM} will either
return H2 or H3 since the driver passes the library an object comparison
function that ignores the A-TCAM / C-TCAM indication.
This can eventually lead to nested objects which are not supported by
the library [1].
Fix by removing the object comparison function from both the driver and
the library as the driver was the only user. That way the lookup will
only return exact matches.
I do not have a reliable reproducer that can reproduce the issue in a
timely manner, but before the fix the issue would reproduce in several
minutes and with the fix it does not reproduce in over an hour.
Note that the current usefulness of the hints is limited because they
include the C-TCAM indication and represent aggregation that cannot
actually happen. This will be addressed in net-next.
[1]
WARNING: CPU: 0 PID: 153 at lib/objagg.c:170 objagg_obj_parent_assign+0xb5/0xd0
Modules linked in:
CPU: 0 PID: 153 Comm: kworker/0:18 Not tainted 6.9.0-rc6-custom-g70fbc2c1c38b #42
Hardware name: Mellanox Technologies Ltd. MSN3700C/VMOD0008, BIOS 5.11 10/10/2018
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:objagg_obj_parent_assign+0xb5/0xd0
[...]
Call Trace:
<TASK>
__objagg_obj_get+0x2bb/0x580
objagg_obj_get+0xe/0x80
mlxsw_sp_acl_erp_mask_get+0xb5/0xf0
mlxsw_sp_acl_atcam_entry_add+0xe8/0x3c0
mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0
mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270
mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510
process_one_work+0x151/0x370
Published Aug 21, 2024 · Updated Aug 5, 2026
High · CVSS 8.1
In the Linux kernel, the following vulnerability has been resolved:
xfrm: Fix input error path memory access
When there is a misconfiguration of input state slow path
KASAN report error. Fix this error.
west login:
[ 52.987278] eth1: renamed from veth11
[ 53.078814] eth1: renamed from veth21
[ 53.181355] eth1: renamed from veth31
[ 54.921702] ==================================================================
[ 54.922602] BUG: KASAN: wild-memory-access in xfrmi_rcv_cb+0x2d/0x295
[ 54.923393] Read of size 8 at addr 6b6b6b6b00000000 by task ping/512
[ 54.924169]
[ 54.924386] CPU: 0 PID: 512 Comm: ping Not tainted 6.9.0-08574-gcd29a4313a1b #25
[ 54.925290] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 54.926401] Call Trace:
[ 54.926731] <IRQ>
[ 54.927009] dump_stack_lvl+0x2a/0x3b
[ 54.927478] kasan_report+0x84/0xa6
[ 54.927930] ? xfrmi_rcv_cb+0x2d/0x295
[ 54.928410] xfrmi_rcv_cb+0x2d/0x295
[ 54.928872] ? xfrm4_rcv_cb+0x3d/0x5e
[ 54.929354] xfrm4_rcv_cb+0x46/0x5e
[ 54.929804] xfrm_rcv_cb+0x7e/0xa1
[ 54.930240] xfrm_input+0x1b3a/0x1b96
[ 54.930715] ? xfrm_offload+0x41/0x41
[ 54.931182] ? raw_rcv+0x292/0x292
[ 54.931617] ? nf_conntrack_confirm+0xa2/0xa2
[ 54.932158] ? skb_sec_path+0xd/0x3f
[ 54.932610] ? xfrmi_input+0x90/0xce
[ 54.933066] xfrm4_esp_rcv+0x33/0x54
[ 54.933521] ip_protocol_deliver_rcu+0xd7/0x1b2
[ 54.934089] ip_local_deliver_finish+0x110/0x120
[ 54.934659] ? ip_protocol_deliver_rcu+0x1b2/0x1b2
[ 54.935248] NF_HOOK.constprop.0+0xf8/0x138
[ 54.935767] ? ip_sublist_rcv_finish+0x68/0x68
[ 54.936317] ? secure_tcpv6_ts_off+0x23/0x168
[ 54.936859] ? ip_protocol_deliver_rcu+0x1b2/0x1b2
[ 54.937454] ? __xfrm_policy_check2.constprop.0+0x18d/0x18d
[ 54.938135] NF_HOOK.constprop.0+0xf8/0x138
[ 54.938663] ? ip_sublist_rcv_finish+0x68/0x68
[ 54.939220] ? __xfrm_policy_check2.constprop.0+0x18d/0x18d
[ 54.939904] ? ip_local_deliver_finish+0x120/0x120
[ 54.940497] __netif_receive_skb_one_core+0xc9/0x107
[ 54.941121] ? __netif_receive_skb_list_core+0x1c2/0x1c2
[ 54.941771] ? blk_mq_start_stopped_hw_queues+0xc7/0xf9
[ 54.942413] ? blk_mq_start_stopped_hw_queue+0x38/0x38
[ 54.943044] ? virtqueue_get_buf_ctx+0x295/0x46b
[ 54.943618] process_backlog+0xb3/0x187
[ 54.944102] __napi_poll.constprop.0+0x57/0x1a7
[ 54.944669] net_rx_action+0x1cb/0x380
[ 54.945150] ? __napi_poll.constprop.0+0x1a7/0x1a7
[ 54.945744] ? vring_new_virtqueue+0x17a/0x17a
[ 54.946300] ? note_interrupt+0x2cd/0x367
[ 54.946805] handle_softirqs+0x13c/0x2c9
[ 54.947300] do_softirq+0x5f/0x7d
[ 54.947727] </IRQ>
[ 54.948014] <TASK>
[ 54.948300] __local_bh_enable_ip+0x48/0x62
[ 54.948832] __neigh_event_send+0x3fd/0x4ca
[ 54.949361] neigh_resolve_output+0x1e/0x210
[ 54.949896] ip_finish_output2+0x4bf/0x4f0
[ 54.950410] ? __ip_finish_output+0x171/0x1b8
[ 54.950956] ip_send_skb+0x25/0x57
[ 54.951390] raw_sendmsg+0xf95/0x10c0
[ 54.951850] ? check_new_pages+0x45/0x71
[ 54.952343] ? raw_hash_sk+0x21b/0x21b
[ 54.952815] ? kernel_init_pages+0x42/0x51
[ 54.953337] ? prep_new_page+0x44/0x51
[ 54.953811] ? get_page_from_freelist+0x72b/0x915
[ 54.954390] ? signal_pending_state+0x77/0x77
[ 54.954936] ? preempt_count_sub+0x14/0xb3
[ 54.955450] ? __might_resched+0x8a/0x240
[ 54.955951] ? __might_sleep+0x25/0xa0
[ 54.956424] ? first_zones_zonelist+0x2c/0x43
[ 54.956977] ? __rcu_read_lock+0x2d/0x3a
[ 54.957476] ? __pte_offset_map+0x32/0xa4
[ 54.957980] ? __might_resched+0x8a/0x240
[ 54.958483] ? __might_sleep+0x25/0xa0
[ 54.958963] ? inet_send_prepare+0x54/0x54
[ 54.959478] ? sock_sendmsg_nosec+0x42/0x6c
[ 54.960000] sock_sendmsg_nosec+0x42/0x6c
[ 54.960502] __sys_sendto+0x15d/0x1cc
[ 54.960966] ? __x64_sys_getpeername+0x44/0x44
[ 54.961522] ? __handle_mm_fault+0x679/0xae4
[ 54.962068] ? find_vma+0x6b/0x
---truncated---
Published Aug 21, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
media: pci: ivtv: Add check for DMA map result
In case DMA fails, 'dma->SG_length' is 0. This value is later used to
access 'dma->SGarray[dma->SG_length - 1]', which will cause out of
bounds access.
Add check to return early on invalid value. Adjust warnings accordingly.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Published Aug 21, 2024 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
RDMA/hns: Fix soft lockup under heavy CEQE load
CEQEs are handled in interrupt handler currently. This may cause the
CPU core staying in interrupt context too long and lead to soft lockup
under heavy load.
Handle CEQEs in BH workqueue and set an upper limit for the number of
CEQE handled by a single call of work handler.
Published Aug 21, 2024 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix CT entry update leaks of modify header context
The cited commit allocates a new modify header to replace the old
one when updating CT entry. But if failed to allocate a new one, eg.
exceed the max number firmware can support, modify header will be
an error pointer that will trigger a panic when deallocating it. And
the old modify header point is copied to old attr. When the old
attr is freed, the old modify header is lost.
Fix it by restoring the old attr to attr when failed to allocate a
new modify header context. So when the CT entry is freed, the right
modify header context will be freed. And the panic of accessing
error pointer is also fixed.
Published Aug 20, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
jfs: Fix array-index-out-of-bounds in diFree
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
dma: fix call order in dmam_free_coherent
dmam_free_coherent() frees a DMA allocation, which makes the
freed vaddr available for reuse, then calls devres_destroy()
to remove and free the data structure used to track the DMA
allocation. Between the two calls, it is possible for a
concurrent task to make an allocation with the same vaddr
and add it to the devres list.
If this happens, there will be two entries in the devres list
with the same vaddr and devres_destroy() can free the wrong
entry, triggering the WARN_ON() in dmam_match.
Fix by destroying the devres entry before freeing the DMA
allocation.
kokonut //net/encryption
http://sponge2/b9145fe6-0f72-4325-ac2f-a84d81075b03
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7
In the Linux kernel, the following vulnerability has been resolved:
cgroup/cpuset: Prevent UAF in proc_cpuset_show()
An UAF can happen when /proc/cpuset is read as reported in [1].
This can be reproduced by the following methods:
1.add an mdelay(1000) before acquiring the cgroup_lock In the
cgroup_path_ns function.
2.$cat /proc/<pid>/cpuset repeatly.
3.$mount -t cgroup -o cpuset cpuset /sys/fs/cgroup/cpuset/
$umount /sys/fs/cgroup/cpuset/ repeatly.
The race that cause this bug can be shown as below:
(umount) | (cat /proc/<pid>/cpuset)
css_release | proc_cpuset_show
css_release_work_fn | css = task_get_css(tsk, cpuset_cgrp_id);
css_free_rwork_fn | cgroup_path_ns(css->cgroup, ...);
cgroup_destroy_root | mutex_lock(&cgroup_mutex);
rebind_subsystems |
cgroup_free_root |
| // cgrp was freed, UAF
| cgroup_path_ns_locked(cgrp,..);
When the cpuset is initialized, the root node top_cpuset.css.cgrp
will point to &cgrp_dfl_root.cgrp. In cgroup v1, the mount operation will
allocate cgroup_root, and top_cpuset.css.cgrp will point to the allocated
&cgroup_root.cgrp. When the umount operation is executed,
top_cpuset.css.cgrp will be rebound to &cgrp_dfl_root.cgrp.
The problem is that when rebinding to cgrp_dfl_root, there are cases
where the cgroup_root allocated by setting up the root for cgroup v1
is cached. This could lead to a Use-After-Free (UAF) if it is
subsequently freed. The descendant cgroups of cgroup v1 can only be
freed after the css is released. However, the css of the root will never
be released, yet the cgroup_root should be freed when it is unmounted.
This means that obtaining a reference to the css of the root does
not guarantee that css.cgrp->root will not be freed.
Fix this problem by using rcu_read_lock in proc_cpuset_show().
As cgroup_root is kfree_rcu after commit d23b5c577715
("cgroup: Make operations on the cgroup root_list RCU safe"),
css->cgroup won't be freed during the critical section.
To call cgroup_path_ns_locked, css_set_lock is needed, so it is safe to
replace task_get_css with task_css.
[1] https://syzkaller.appspot.com/bug?extid=9b1ff7be974a403aa4cd
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: fix TTLM teardown work
The worker calculates the wrong sdata pointer, so if it ever
runs, it'll crash. Fix that.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix invalid memory access while processing fragmented packets
The monitor ring and the reo reinject ring share the same ring mask index.
When the driver receives an interrupt for the reo reinject ring, the
monitor ring is also processed, leading to invalid memory access. Since
monitor support is not yet enabled in ath12k, the ring mask for the monitor
ring should be removed.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.1.1-00209-QCAHKSWPL_SILICONZ-1
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
lib: objagg: Fix general protection fault
The library supports aggregation of objects into other objects only if
the parent object does not have a parent itself. That is, nesting is not
supported.
Aggregation happens in two cases: Without and with hints, where hints
are a pre-computed recommendation on how to aggregate the provided
objects.
Nesting is not possible in the first case due to a check that prevents
it, but in the second case there is no check because the assumption is
that nesting cannot happen when creating objects based on hints. The
violation of this assumption leads to various warnings and eventually to
a general protection fault [1].
Before fixing the root cause, error out when nesting happens and warn.
[1]
general protection fault, probably for non-canonical address 0xdead000000000d90: 0000 [#1] PREEMPT SMP PTI
CPU: 1 PID: 1083 Comm: kworker/1:9 Tainted: G W 6.9.0-rc6-custom-gd9b4f1cca7fb #7
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:mlxsw_sp_acl_erp_bf_insert+0x25/0x80
[...]
Call Trace:
<TASK>
mlxsw_sp_acl_atcam_entry_add+0x256/0x3c0
mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0
mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270
mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510
process_one_work+0x151/0x370
worker_thread+0x2cb/0x3e0
kthread+0xd0/0x100
ret_from_fork+0x34/0x50
ret_from_fork_asm+0x1a/0x30
</TASK>
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
udf: Fix bogus checksum computation in udf_rename()
Syzbot reports uninitialized memory access in udf_rename() when updating
checksum of '..' directory entry of a moved directory. This is indeed
true as we pass on-stack diriter.fi to the udf_update_tag() and because
that has only struct fileIdentDesc included in it and not the impUse or
name fields, the checksumming function is going to checksum random stack
contents beyond the end of the structure. This is actually harmless
because the following udf_fiiter_write_fi() will recompute the checksum
from on-disk buffers where everything is properly included. So all that
is needed is just removing the bogus calculation.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG
When BPF_TRAMP_F_CALL_ORIG is set, the trampoline calls
__bpf_tramp_enter() and __bpf_tramp_exit() functions, passing them
the struct bpf_tramp_image *im pointer as an argument in R0.
The trampoline generation code uses emit_addr_mov_i64() to emit
instructions for moving the bpf_tramp_image address into R0, but
emit_addr_mov_i64() assumes the address to be in the vmalloc() space
and uses only 48 bits. Because bpf_tramp_image is allocated using
kzalloc(), its address can use more than 48-bits, in this case the
trampoline will pass an invalid address to __bpf_tramp_enter/exit()
causing a kernel crash.
Fix this by using emit_a64_mov_i64() in place of emit_addr_mov_i64()
as it can work with addresses that are greater than 48-bits.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
s390/uv: Don't call folio_wait_writeback() without a folio reference
folio_wait_writeback() requires that no spinlocks are held and that
a folio reference is held, as documented. After we dropped the PTL, the
folio could get freed concurrently. So grab a temporary reference.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
leds: trigger: Unregister sysfs attributes before calling deactivate()
Triggers which have trigger specific sysfs attributes typically store
related data in trigger-data allocated by the activate() callback and
freed by the deactivate() callback.
Calling device_remove_groups() after calling deactivate() leaves a window
where the sysfs attributes show/store functions could be called after
deactivation and then operate on the just freed trigger-data.
Move the device_remove_groups() call to before deactivate() to close
this race window.
This also makes the deactivation path properly do things in reverse order
of the activation path which calls the activate() callback before calling
device_add_groups().
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
iio: Fix the sorting functionality in iio_gts_build_avail_time_table
The sorting in iio_gts_build_avail_time_table is not working as intended.
It could result in an out-of-bounds access when the time is zero.
Here are more details:
1. When the gts->itime_table[i].time_us is zero, e.g., the time
sequence is `3, 0, 1`, the inner for-loop will not terminate and do
out-of-bound writes. This is because once `times[j] > new`, the value
`new` will be added in the current position and the `times[j]` will be
moved to `j+1` position, which makes the if-condition always hold.
Meanwhile, idx will be added one, making the loop keep running without
termination and out-of-bound write.
2. If none of the gts->itime_table[i].time_us is zero, the elements
will just be copied without being sorted as described in the comment
"Sort times from all tables to one and remove duplicates".
For more details, please refer to
https://lore.kernel.org/all/6dd0d822-046c-4dd2-9532-79d7ab96ec05@gmail.com.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Revise lpfc_prep_embed_io routine with proper endian macro usages
On big endian architectures, it is possible to run into a memory out of
bounds pointer dereference when FCP targets are zoned.
In lpfc_prep_embed_io, the memcpy(ptr, fcp_cmnd, sgl->sge_len) is
referencing a little endian formatted sgl->sge_len value. So, the memcpy
can cause big endian systems to crash.
Redefine the *sgl ptr as a struct sli4_sge_le to make it clear that we are
referring to a little endian formatted data structure. And, update the
routine with proper le32_to_cpu macro usages.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
landlock: Don't lose track of restrictions on cred_transfer
When a process' cred struct is replaced, this _almost_ always invokes
the cred_prepare LSM hook; but in one special case (when
KEYCTL_SESSION_TO_PARENT updates the parent's credentials), the
cred_transfer LSM hook is used instead. Landlock only implements the
cred_prepare hook, not cred_transfer, so KEYCTL_SESSION_TO_PARENT causes
all information on Landlock restrictions to be lost.
This basically means that a process with the ability to use the fork()
and keyctl() syscalls can get rid of all Landlock restrictions on
itself.
Fix it by adding a cred_transfer hook that does the same thing as the
existing cred_prepare hook. (Implemented by having hook_cred_prepare()
call hook_cred_transfer() so that the two functions are less likely to
accidentally diverge in the future.)
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix extent map use-after-free when adding pages to compressed bio
At add_ra_bio_pages() we are accessing the extent map to calculate
'add_size' after we dropped our reference on the extent map, resulting
in a use-after-free. Fix this by computing 'add_size' before dropping our
extent map reference.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
media: venus: fix use after free in vdec_close
There appears to be a possible use after free with vdec_close().
The firmware will add buffer release work to the work queue through
HFI callbacks as a normal part of decoding. Randomly closing the
decoder device from userspace during normal decoding can incur
a read after free for inst.
Fix it by cancelling the work in vdec_close.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
hfs: fix to initialize fields of hfs_inode_info after hfs_alloc_inode()
Syzbot reports uninitialized value access issue as below:
loop0: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in hfs_revalidate_dentry+0x307/0x3f0 fs/hfs/sysdep.c:30
hfs_revalidate_dentry+0x307/0x3f0 fs/hfs/sysdep.c:30
d_revalidate fs/namei.c:862 [inline]
lookup_fast+0x89e/0x8e0 fs/namei.c:1649
walk_component fs/namei.c:2001 [inline]
link_path_walk+0x817/0x1480 fs/namei.c:2332
path_lookupat+0xd9/0x6f0 fs/namei.c:2485
filename_lookup+0x22e/0x740 fs/namei.c:2515
user_path_at_empty+0x8b/0x390 fs/namei.c:2924
user_path_at include/linux/namei.h:57 [inline]
do_mount fs/namespace.c:3689 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x66b/0x810 fs/namespace.c:3875
__x64_sys_mount+0xe4/0x140 fs/namespace.c:3875
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
BUG: KMSAN: uninit-value in hfs_ext_read_extent fs/hfs/extent.c:196 [inline]
BUG: KMSAN: uninit-value in hfs_get_block+0x92d/0x1620 fs/hfs/extent.c:366
hfs_ext_read_extent fs/hfs/extent.c:196 [inline]
hfs_get_block+0x92d/0x1620 fs/hfs/extent.c:366
block_read_full_folio+0x4ff/0x11b0 fs/buffer.c:2271
hfs_read_folio+0x55/0x60 fs/hfs/inode.c:39
filemap_read_folio+0x148/0x4f0 mm/filemap.c:2426
do_read_cache_folio+0x7c8/0xd90 mm/filemap.c:3553
do_read_cache_page mm/filemap.c:3595 [inline]
read_cache_page+0xfb/0x2f0 mm/filemap.c:3604
read_mapping_page include/linux/pagemap.h:755 [inline]
hfs_btree_open+0x928/0x1ae0 fs/hfs/btree.c:78
hfs_mdb_get+0x260c/0x3000 fs/hfs/mdb.c:204
hfs_fill_super+0x1fb1/0x2790 fs/hfs/super.c:406
mount_bdev+0x628/0x920 fs/super.c:1359
hfs_mount+0xcd/0xe0 fs/hfs/super.c:456
legacy_get_tree+0x167/0x2e0 fs/fs_context.c:610
vfs_get_tree+0xdc/0x5d0 fs/super.c:1489
do_new_mount+0x7a9/0x16f0 fs/namespace.c:3145
path_mount+0xf98/0x26a0 fs/namespace.c:3475
do_mount fs/namespace.c:3488 [inline]
__do_sys_mount fs/namespace.c:3697 [inline]
__se_sys_mount+0x919/0x9e0 fs/namespace.c:3674
__ia32_sys_mount+0x15b/0x1b0 fs/namespace.c:3674
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
entry_SYSENTER_compat_after_hwframe+0x70/0x82
Uninit was created at:
__alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4590
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2190 [inline]
allocate_slab mm/slub.c:2354 [inline]
new_slab+0x2d7/0x1400 mm/slub.c:2407
___slab_alloc+0x16b5/0x3970 mm/slub.c:3540
__slab_alloc mm/slub.c:3625 [inline]
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
kmem_cache_alloc_lru+0x64d/0xb30 mm/slub.c:3879
alloc_inode_sb include/linux/fs.h:3018 [inline]
hfs_alloc_inode+0x5a/0xc0 fs/hfs/super.c:165
alloc_inode+0x83/0x440 fs/inode.c:260
new_inode_pseudo fs/inode.c:1005 [inline]
new_inode+0x38/0x4f0 fs/inode.c:1031
hfs_new_inode+0x61/0x1010 fs/hfs/inode.c:186
hfs_mkdir+0x54/0x250 fs/hfs/dir.c:228
vfs_mkdir+0x49a/0x700 fs/namei.c:4126
do_mkdirat+0x529/0x810 fs/namei.c:4149
__do_sys_mkdirat fs/namei.c:4164 [inline]
__se_sys_mkdirat fs/namei.c:4162 [inline]
__x64_sys_mkdirat+0xc8/0x120 fs/namei.c:4162
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
It missed to initialize .tz_secondswest, .cached_start and .cached_blocks
fields in struct hfs_inode_info after hfs_alloc_inode(), fix it.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
udf: Avoid using corrupted block bitmap buffer
When the filesystem block bitmap is corrupted, we detect the corruption
while loading the bitmap and fail the allocation with error. However the
next allocation from the same bitmap will notice the bitmap buffer is
already loaded and tries to allocate from the bitmap with mixed results
(depending on the exact nature of the bitmap corruption). Fix the
problem by using BH_verified bit to indicate whether the bitmap is valid
or not.
Published Aug 17, 2024 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
ext4: make sure the first directory block is not a hole
The syzbot constructs a directory that has no dirblock but is non-inline,
i.e. the first directory block is a hole. And no errors are reported when
creating files in this directory in the following flow.
ext4_mknod
...
ext4_add_entry
// Read block 0
ext4_read_dirblock(dir, block, DIRENT)
bh = ext4_bread(NULL, inode, block, 0)
if (!bh && (type == INDEX || type == DIRENT_HTREE))
// The first directory block is a hole
// But type == DIRENT, so no error is reported.
After that, we get a directory block without '.' and '..' but with a valid
dentry. This may cause some code that relies on dot or dotdot (such as
make_indexed_dir()) to crash.
Therefore when ext4_read_dirblock() finds that the first directory block
is a hole report that the filesystem is corrupted and return an error to
avoid loading corrupted data from disk causing something bad.
Published Aug 17, 2024 · Updated Aug 5, 2026
