In the Linux kernel, the following vulnerability has been resolved:
nfsd: provide locking for v4_end_grace
Writing to v4_end_grace can race with server shutdown and result in
memory being accessed after it was freed - reclaim_str_hashtbl in
particularly.
We cannot hold nfsd_mutex across the nfsd4_end_grace() call as that is
held while client_tracking_op->init() is called and that can wait for
an upcall to nfsdcltrack which can write to v4_end_grace, resulting in a
deadlock.
nfsd4_end_grace() is also called by the landromat work queue and this
doesn't require locking as server shutdown will stop the work and wait
for it before freeing anything that nfsd4_end_grace() might access.
However, we must be sure that writing to v4_end_grace doesn't restart
the work item after shutdown has already waited for it. For this we
add a new flag protected with nn->client_lock. It is set only while it
is safe to make client tracking calls, and v4_end_grace only schedules
work while the flag is set with the spinlock held.
So this patch adds a nfsd_net field "client_tracking_active" which is
set as described. Another field "grace_end_forced", is set when
v4_end_grace is written. After this is set, and providing
client_tracking_active is set, the laundromat is scheduled.
This "grace_end_forced" field bypasses other checks for whether the
grace period has finished.
This resolves a race which can result in use-after-free.
References
Configurations
Configuration 1 (hide)
|
History
26 Feb 2026, 18:48
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Linux
Linux linux Kernel |
|
| CPE | cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* |
|
| CWE | CWE-416 | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.8 |
| References | () https://git.kernel.org/stable/c/06600719d0f7a723811c45e4d51f5b742f345309 - Patch | |
| References | () https://git.kernel.org/stable/c/2857bd59feb63fcf40fe4baf55401baea6b4feb4 - Patch | |
| References | () https://git.kernel.org/stable/c/34eb22836e0cdba093baac66599d68c4cd245a9d - Patch | |
| References | () https://git.kernel.org/stable/c/53f07d095e7e680c5e4569a55a019f2c0348cdc6 - Patch | |
| References | () https://git.kernel.org/stable/c/ba4811c8b433bfa681729ca42cc62b6034f223b0 - Patch | |
| References | () https://git.kernel.org/stable/c/ca97360860eb02e3ae4ba42c19b439a0fcecbf06 - Patch | |
| References | () https://git.kernel.org/stable/c/e8bfa2401d4c51eca6e48e9b33c798828ca9df61 - Patch |
23 Jan 2026, 16:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-01-23 16:15
Updated : 2026-02-26 18:48
NVD link : CVE-2026-22980
Mitre link : CVE-2026-22980
CVE.ORG link : CVE-2026-22980
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
Use After Free