| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: transport_ipc: validate payload size before reading handle
handle_response() dereferences the payload as a 4-byte handle without
verifying that the declared payload size is at least 4 bytes. A malformed
or truncated message from ksmbd.mountd can lead to a 4-byte read past the
declared payload size. Validate the size before dereferencing.
This is a minimal fix to guard the initial handle read. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Fix NULL pointer deference in try_to_register_card
In try_to_register_card(), the return value of usb_ifnum_to_if() is
passed directly to usb_interface_claimed() without a NULL check, which
will lead to a NULL pointer dereference when creating an invalid
USB audio device. Fix this by adding a check to ensure the interface
pointer is valid before passing it to usb_interface_claimed(). |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: Fix missing pointer check in hda_component_manager_init function
The __component_match_add function may assign the 'matchptr' pointer
the value ERR_PTR(-ENOMEM), which will subsequently be dereferenced.
The call stack leading to the error looks like this:
hda_component_manager_init
|-> component_match_add
|-> component_match_add_release
|-> __component_match_add ( ... ,**matchptr, ... )
|-> *matchptr = ERR_PTR(-ENOMEM); // assign
|-> component_master_add_with_match( ... match)
|-> component_match_realloc(match, match->num); // dereference
Add IS_ERR() check to prevent the crash.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: cs35l41: Fix NULL pointer dereference in cs35l41_get_acpi_mute_state()
Return value of a function acpi_evaluate_dsm() is dereferenced without
checking for NULL, but it is usually checked for this function.
acpi_evaluate_dsm() may return NULL, when acpi_evaluate_object() returns
acpi_status other than ACPI_SUCCESS, so add a check to prevent the crach.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
cifs: parse_dfs_referrals: prevent oob on malformed input
Malicious SMB server can send invalid reply to FSCTL_DFS_GET_REFERRALS
- reply smaller than sizeof(struct get_dfs_referral_rsp)
- reply with number of referrals smaller than NumberOfReferrals in the
header
Processing of such replies will cause oob.
Return -EINVAL error on such replies to prevent oob-s. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not assert we found block group item when creating free space tree
Currently, when building a free space tree at populate_free_space_tree(),
if we are not using the block group tree feature, we always expect to find
block group items (either extent items or a block group item with key type
BTRFS_BLOCK_GROUP_ITEM_KEY) when we search the extent tree with
btrfs_search_slot_for_read(), so we assert that we found an item. However
this expectation is wrong since we can have a new block group created in
the current transaction which is still empty and for which we still have
not added the block group's item to the extent tree, in which case we do
not have any items in the extent tree associated to the block group.
The insertion of a new block group's block group item in the extent tree
happens at btrfs_create_pending_block_groups() when it calls the helper
insert_block_group_item(). This typically is done when a transaction
handle is released, committed or when running delayed refs (either as
part of a transaction commit or when serving tickets for space reservation
if we are low on free space).
So remove the assertion at populate_free_space_tree() even when the block
group tree feature is not enabled and update the comment to mention this
case.
Syzbot reported this with the following stack trace:
BTRFS info (device loop3 state M): rebuilding free space tree
assertion failed: ret == 0 :: 0, in fs/btrfs/free-space-tree.c:1115
------------[ cut here ]------------
kernel BUG at fs/btrfs/free-space-tree.c:1115!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 6352 Comm: syz.3.25 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:populate_free_space_tree+0x700/0x710 fs/btrfs/free-space-tree.c:1115
Code: ff ff e8 d3 (...)
RSP: 0018:ffffc9000430f780 EFLAGS: 00010246
RAX: 0000000000000043 RBX: ffff88805b709630 RCX: fea61d0e2e79d000
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc9000430f8b0 R08: ffffc9000430f4a7 R09: 1ffff92000861e94
R10: dffffc0000000000 R11: fffff52000861e95 R12: 0000000000000001
R13: 1ffff92000861f00 R14: dffffc0000000000 R15: 0000000000000000
FS: 00007f424d9fe6c0(0000) GS:ffff888125afc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd78ad212c0 CR3: 0000000076d68000 CR4: 00000000003526f0
Call Trace:
<TASK>
btrfs_rebuild_free_space_tree+0x1ba/0x6d0 fs/btrfs/free-space-tree.c:1364
btrfs_start_pre_rw_mount+0x128f/0x1bf0 fs/btrfs/disk-io.c:3062
btrfs_remount_rw fs/btrfs/super.c:1334 [inline]
btrfs_reconfigure+0xaed/0x2160 fs/btrfs/super.c:1559
reconfigure_super+0x227/0x890 fs/super.c:1076
do_remount fs/namespace.c:3279 [inline]
path_mount+0xd1a/0xfe0 fs/namespace.c:4027
do_mount fs/namespace.c:4048 [inline]
__do_sys_mount fs/namespace.c:4236 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4213
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f424e39066a
Code: d8 64 89 02 (...)
RSP: 002b:00007f424d9fde68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f424d9fdef0 RCX: 00007f424e39066a
RDX: 0000200000000180 RSI: 0000200000000380 RDI: 0000000000000000
RBP: 0000200000000180 R08: 00007f424d9fdef0 R09: 0000000000000020
R10: 0000000000000020 R11: 0000000000000246 R12: 0000200000000380
R13: 00007f424d9fdeb0 R14: 0000000000000000 R15: 00002000000002c0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix memory leaks when rejecting a non SINGLE data profile without an RST
At the end of btrfs_load_block_group_zone_info() the first thing we do
is to ensure that if the mapping type is not a SINGLE one and there is
no RAID stripe tree, then we return early with an error.
Doing that, though, prevents the code from running the last calls from
this function which are about freeing memory allocated during its
run. Hence, in this case, instead of returning early, we set the ret
value and fall through the rest of the cleanup code. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Prevent access to vCPU events before init
Another day, another syzkaller bug. KVM erroneously allows userspace to
pend vCPU events for a vCPU that hasn't been initialized yet, leading to
KVM interpreting a bunch of uninitialized garbage for routing /
injecting the exception.
In one case the injection code and the hyp disagree on whether the vCPU
has a 32bit EL1 and put the vCPU into an illegal mode for AArch64,
tripping the BUG() in exception_target_el() during the next injection:
kernel BUG at arch/arm64/kvm/inject_fault.c:40!
Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
CPU: 3 UID: 0 PID: 318 Comm: repro Not tainted 6.17.0-rc4-00104-g10fd0285305d #6 PREEMPT
Hardware name: linux,dummy-virt (DT)
pstate: 21402009 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : exception_target_el+0x88/0x8c
lr : pend_serror_exception+0x18/0x13c
sp : ffff800082f03a10
x29: ffff800082f03a10 x28: ffff0000cb132280 x27: 0000000000000000
x26: 0000000000000000 x25: ffff0000c2a99c20 x24: 0000000000000000
x23: 0000000000008000 x22: 0000000000000002 x21: 0000000000000004
x20: 0000000000008000 x19: ffff0000c2a99c20 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 00000000200000c0
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : ffff800082f03af8 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff800080f621f0 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 000000000040009b x1 : 0000000000000003 x0 : ffff0000c2a99c20
Call trace:
exception_target_el+0x88/0x8c (P)
kvm_inject_serror_esr+0x40/0x3b4
__kvm_arm_vcpu_set_events+0xf0/0x100
kvm_arch_vcpu_ioctl+0x180/0x9d4
kvm_vcpu_ioctl+0x60c/0x9f4
__arm64_sys_ioctl+0xac/0x104
invoke_syscall+0x48/0x110
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x34/0xf0
el0t_64_sync_handler+0xa0/0xe4
el0t_64_sync+0x198/0x19c
Code: f946bc01 b4fffe61 9101e020 17fffff2 (d4210000)
Reject the ioctls outright as no sane VMM would call these before
KVM_ARM_VCPU_INIT anyway. Even if it did the exception would've been
thrown away by the eventual reset of the vCPU's state. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix potential null deref in ext4_mb_init()
In ext4_mb_init(), ext4_mb_avg_fragment_size_destroy() may be called
when sbi->s_mb_avg_fragment_size remains uninitialized (e.g., if groupinfo
slab cache allocation fails). Since ext4_mb_avg_fragment_size_destroy()
lacks null pointer checking, this leads to a null pointer dereference.
==================================================================
EXT4-fs: no memory for groupinfo slab cache
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: Oops: 0002 [#1] SMP PTI
CPU:2 UID: 0 PID: 87 Comm:mount Not tainted 6.17.0-rc2 #1134 PREEMPT(none)
RIP: 0010:_raw_spin_lock_irqsave+0x1b/0x40
Call Trace:
<TASK>
xa_destroy+0x61/0x130
ext4_mb_init+0x483/0x540
__ext4_fill_super+0x116d/0x17b0
ext4_fill_super+0xd3/0x280
get_tree_bdev_flags+0x132/0x1d0
vfs_get_tree+0x29/0xd0
do_new_mount+0x197/0x300
__x64_sys_mount+0x116/0x150
do_syscall_64+0x50/0x1c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
==================================================================
Therefore, add necessary null check to ext4_mb_avg_fragment_size_destroy()
to prevent this issue. The same fix is also applied to
ext4_mb_largest_free_orders_destroy(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: asix: hold PM usage ref to avoid PM/MDIO + RTNL deadlock
Prevent USB runtime PM (autosuspend) for AX88772* in bind.
usbnet enables runtime PM (autosuspend) by default, so disabling it via
the usb_driver flag is ineffective. On AX88772B, autosuspend shows no
measurable power saving with current driver (no link partner, admin
up/down). The ~0.453 W -> ~0.248 W drop on v6.1 comes from phylib powering
the PHY off on admin-down, not from USB autosuspend.
The real hazard is that with runtime PM enabled, ndo_open() (under RTNL)
may synchronously trigger autoresume (usb_autopm_get_interface()) into
asix_resume() while the USB PM lock is held. Resume paths then invoke
phylink/phylib and MDIO, which also expect RTNL, leading to possible
deadlocks or PM lock vs MDIO wake issues.
To avoid this, keep the device runtime-PM active by taking a usage
reference in ax88772_bind() and dropping it in unbind(). A non-zero PM
usage count blocks runtime suspend regardless of userspace policy
(.../power/control - pm_runtime_allow/forbid), making this approach
robust against sysfs overrides.
Holding a runtime-PM usage ref does not affect system-wide suspend;
system sleep/resume callbacks continue to run as before. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: Intel: bytcr_rt5651: Fix invalid quirk input mapping
When an invalid value is passed via quirk option, currently
bytcr_rt5640 driver just ignores and leaves as is, which may lead to
unepxected results like OOB access.
This patch adds the sanity check and corrects the input mapping to the
certain default value if an invalid value is passed. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel: Fix IA32_PMC_x_CFG_B MSRs access error
When running perf_fuzzer on PTL, sometimes the below "unchecked MSR
access error" is seen when accessing IA32_PMC_x_CFG_B MSRs.
[ 55.611268] unchecked MSR access error: WRMSR to 0x1986 (tried to write 0x0000000200000001) at rIP: 0xffffffffac564b28 (native_write_msr+0x8/0x30)
[ 55.611280] Call Trace:
[ 55.611282] <TASK>
[ 55.611284] ? intel_pmu_config_acr+0x87/0x160
[ 55.611289] intel_pmu_enable_acr+0x6d/0x80
[ 55.611291] intel_pmu_enable_event+0xce/0x460
[ 55.611293] x86_pmu_start+0x78/0xb0
[ 55.611297] x86_pmu_enable+0x218/0x3a0
[ 55.611300] ? x86_pmu_enable+0x121/0x3a0
[ 55.611302] perf_pmu_enable+0x40/0x50
[ 55.611307] ctx_resched+0x19d/0x220
[ 55.611309] __perf_install_in_context+0x284/0x2f0
[ 55.611311] ? __pfx_remote_function+0x10/0x10
[ 55.611314] remote_function+0x52/0x70
[ 55.611317] ? __pfx_remote_function+0x10/0x10
[ 55.611319] generic_exec_single+0x84/0x150
[ 55.611323] smp_call_function_single+0xc5/0x1a0
[ 55.611326] ? __pfx_remote_function+0x10/0x10
[ 55.611329] perf_install_in_context+0xd1/0x1e0
[ 55.611331] ? __pfx___perf_install_in_context+0x10/0x10
[ 55.611333] __do_sys_perf_event_open+0xa76/0x1040
[ 55.611336] __x64_sys_perf_event_open+0x26/0x30
[ 55.611337] x64_sys_call+0x1d8e/0x20c0
[ 55.611339] do_syscall_64+0x4f/0x120
[ 55.611343] entry_SYSCALL_64_after_hwframe+0x76/0x7e
On PTL, GP counter 0 and 1 doesn't support auto counter reload feature,
thus it would trigger a #GP when trying to write 1 on bit 0 of CFG_B MSR
which requires to enable auto counter reload on GP counter 0.
The root cause of causing this issue is the check for auto counter
reload (ACR) counter mask from user space is incorrect in
intel_pmu_acr_late_setup() helper. It leads to an invalid ACR counter
mask from user space could be set into hw.config1 and then written into
CFG_B MSRs and trigger the MSR access warning.
e.g., User may create a perf event with ACR counter mask (config2=0xcb),
and there is only 1 event created, so "cpuc->n_events" is 1.
The correct check condition should be "i + idx >= cpuc->n_events"
instead of "i + idx > cpuc->n_events" (it looks a typo). Otherwise,
the counter mask would traverse twice and an invalid "cpuc->assign[1]"
bit (bit 0) is set into hw.config1 and cause MSR accessing error.
Besides, also check if the ACR counter mask corresponding events are
ACR events. If not, filter out these counter mask. If a event is not a
ACR event, it could be scheduled to an HW counter which doesn't support
ACR. It's invalid to add their counter index in ACR counter mask.
Furthermore, remove the WARN_ON_ONCE() since it's easily triggered as
user could set any invalid ACR counter mask and the warning message
could mislead users. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Check the untrusted offset in FF-A memory share
Verify the offset to prevent OOB access in the hypervisor
FF-A buffer in case an untrusted large enough value
[U32_MAX - sizeof(struct ffa_composite_mem_region) + 1, U32_MAX]
is set from the host kernel. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: fix NULL pointer dereference in __dm_suspend()
There is a race condition between dm device suspend and table load that
can lead to null pointer dereference. The issue occurs when suspend is
invoked before table load completes:
BUG: kernel NULL pointer dereference, address: 0000000000000054
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 6 PID: 6798 Comm: dmsetup Not tainted 6.6.0-g7e52f5f0ca9b #62
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014
RIP: 0010:blk_mq_wait_quiesce_done+0x0/0x50
Call Trace:
<TASK>
blk_mq_quiesce_queue+0x2c/0x50
dm_stop_queue+0xd/0x20
__dm_suspend+0x130/0x330
dm_suspend+0x11a/0x180
dev_suspend+0x27e/0x560
ctl_ioctl+0x4cf/0x850
dm_ctl_ioctl+0xd/0x20
vfs_ioctl+0x1d/0x50
__se_sys_ioctl+0x9b/0xc0
__x64_sys_ioctl+0x19/0x30
x64_sys_call+0x2c4a/0x4620
do_syscall_64+0x9e/0x1b0
The issue can be triggered as below:
T1 T2
dm_suspend table_load
__dm_suspend dm_setup_md_queue
dm_mq_init_request_queue
blk_mq_init_allocated_queue
=> q->mq_ops = set->ops; (1)
dm_stop_queue / dm_wait_for_completion
=> q->tag_set NULL pointer! (2)
=> q->tag_set = set; (3)
Fix this by checking if a valid table (map) exists before performing
request-based suspend and waiting for target I/O. When map is NULL,
skip these table-dependent suspend steps.
Even when map is NULL, no I/O can reach any target because there is
no table loaded; I/O submitted in this state will fail early in the
DM layer. Skipping the table-dependent suspend logic in this case
is safe and avoids NULL pointer dereferences. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: use RCU in ip6_xmit()
Use RCU in ip6_xmit() in order to use dst_dev_rcu() to prevent
possible UAF. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: hisilicon/qm - request reserved interrupt for virtual function
The device interrupt vector 3 is an error interrupt for
physical function and a reserved interrupt for virtual function.
However, the driver has not registered the reserved interrupt for
virtual function. When allocating interrupts, the number of interrupts
is allocated based on powers of two, which includes this interrupt.
When the system enables GICv4 and the virtual function passthrough
to the virtual machine, releasing the interrupt in the driver
triggers a warning.
The WARNING report is:
WARNING: CPU: 62 PID: 14889 at arch/arm64/kvm/vgic/vgic-its.c:852 its_free_ite+0x94/0xb4
Therefore, register a reserved interrupt for VF and set the
IRQF_NO_AUTOEN flag to avoid that warning. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to truncate first page in error path of f2fs_truncate()
syzbot reports a bug as below:
loop0: detected capacity change from 0 to 40427
F2FS-fs (loop0): Wrong SSA boundary, start(3584) end(4096) blocks(3072)
F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock
F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): f2fs_convert_inline_folio: corrupted inline inode ino=3, i_addr[0]:0x1601, run fsck to fix.
------------[ cut here ]------------
kernel BUG at fs/inode.c:753!
RIP: 0010:clear_inode+0x169/0x190 fs/inode.c:753
Call Trace:
<TASK>
evict+0x504/0x9c0 fs/inode.c:810
f2fs_fill_super+0x5612/0x6fa0 fs/f2fs/super.c:5047
get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4324
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
During f2fs_evict_inode(), clear_inode() detects that we missed to truncate
all page cache before destorying inode, that is because in below path, we
will create page #0 in cache, but missed to drop it in error path, let's fix
it.
- evict
- f2fs_evict_inode
- f2fs_truncate
- f2fs_convert_inline_inode
- f2fs_grab_cache_folio
: create page #0 in cache
- f2fs_convert_inline_folio
: sanity check failed, return -EFSCORRUPTED
- clear_inode detects that inode->i_data.nrpages is not zero |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Disable bottom softirqs as part of spin_lock_irq() on PREEMPT_RT
snd_pcm_group_lock_irq() acquires a spinlock_t and disables interrupts
via spin_lock_irq(). This also implicitly disables the handling of
softirqs such as TIMER_SOFTIRQ.
On PREEMPT_RT softirqs are preemptible and spin_lock_irq() does not
disable them. That means a timer can be invoked during spin_lock_irq()
on the same CPU. Due to synchronisations reasons local_bh_disable() has
a per-CPU lock named softirq_ctrl.lock which synchronizes individual
softirq against each other.
syz-bot managed to trigger a lockdep report where softirq_ctrl.lock is
acquired in hrtimer_cancel() in addition to hrtimer_run_softirq(). This
is a possible deadlock.
The softirq_ctrl.lock can not be made part of spin_lock_irq() as this
would lead to too much synchronisation against individual threads on the
system. To avoid the possible deadlock, softirqs must be manually
disabled before the lock is acquired.
Disable softirqs before the lock is acquired on PREEMPT_RT. |
| In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process releases a ublk char device file, any requests
dispatched to the ublk server but not yet completed will retain a ref
value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify
aborting ublk request"), __ublk_fail_req() would decrement the reference
count before completing the failed request. However, that commit
optimized __ublk_fail_req() to call __ublk_complete_rq() directly
without decrementing the request reference count.
The leaked reference count incorrectly allows user copy and zero copy
operations on the completed ublk request. It also triggers the
WARN_ON_ONCE(refcount_read(&io->ref)) warnings in ublk_queue_reinit()
and ublk_deinit_queue().
Commit c5c5eb24ed61 ("ublk: avoid ublk_io_release() called after ublk
char dev is closed") already fixed the issue for ublk devices using
UBLK_F_SUPPORT_ZERO_COPY or UBLK_F_AUTO_BUF_REG. However, the reference
count leak also affects UBLK_F_USER_COPY, the other reference-counted
data copy mode. Fix the condition in ublk_check_and_reset_active_ref()
to include all reference-counted data copy modes. This ensures that any
ublk requests still owned by the ublk server when it exits have their
reference counts reset to 0. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: invalidate dentry cache on failed whiteout creation
F2FS can mount filesystems with corrupted directory depth values that
get runtime-clamped to MAX_DIR_HASH_DEPTH. When RENAME_WHITEOUT
operations are performed on such directories, f2fs_rename performs
directory modifications (updating target entry and deleting source
entry) before attempting to add the whiteout entry via f2fs_add_link.
If f2fs_add_link fails due to the corrupted directory structure, the
function returns an error to VFS, but the partial directory
modifications have already been committed to disk. VFS assumes the
entire rename operation failed and does not update the dentry cache,
leaving stale mappings.
In the error path, VFS does not call d_move() to update the dentry
cache. This results in new_dentry still pointing to the old inode
(new_inode) which has already had its i_nlink decremented to zero.
The stale cache causes subsequent operations to incorrectly reference
the freed inode.
This causes subsequent operations to use cached dentry information that
no longer matches the on-disk state. When a second rename targets the
same entry, VFS attempts to decrement i_nlink on the stale inode, which
may already have i_nlink=0, triggering a WARNING in drop_nlink().
Example sequence:
1. First rename (RENAME_WHITEOUT): file2 → file1
- f2fs updates file1 entry on disk (points to inode 8)
- f2fs deletes file2 entry on disk
- f2fs_add_link(whiteout) fails (corrupted directory)
- Returns error to VFS
- VFS does not call d_move() due to error
- VFS cache still has: file1 → inode 7 (stale!)
- inode 7 has i_nlink=0 (already decremented)
2. Second rename: file3 → file1
- VFS uses stale cache: file1 → inode 7
- Tries to drop_nlink on inode 7 (i_nlink already 0)
- WARNING in drop_nlink()
Fix this by explicitly invalidating old_dentry and new_dentry when
f2fs_add_link fails during whiteout creation. This forces VFS to
refresh from disk on subsequent operations, ensuring cache consistency
even when the rename partially succeeds.
Reproducer:
1. Mount F2FS image with corrupted i_current_depth
2. renameat2(file2, file1, RENAME_WHITEOUT)
3. renameat2(file3, file1, 0)
4. System triggers WARNING in drop_nlink() |