In the Linux kernel, the following vulnerability has been resolved:
net/rds: Fix circular locking dependency in rds_tcp_tune
syzbot reported a circular locking dependency in rds_tcp_tune() where
sk_net_refcnt_upgrade() is called while holding the socket lock:
======================================================
WARNING: possible circular locking dependency detected
======================================================
kworker/u10:8/15040 is trying to acquire lock:
ffffffff8e9aaf80 (fs_reclaim){+.+.}-{0:0},
at: __kmalloc_cache_noprof+0x4b/0x6f0
but task is already holding lock:
ffff88805a3c1ce0 (k-sk_lock-AF_INET6){+.+.}-{0:0},
at: rds_tcp_tune+0xd7/0x930
The issue occurs because sk_net_refcnt_upgrade() performs memory
allocation (via get_net_track() -> ref_tracker_alloc()) while the
socket lock is held, creating a circular dependency with fs_reclaim.
Fix this by moving sk_net_refcnt_upgrade() outside the socket lock
critical section. This is safe because the fields modified by the
sk_net_refcnt_upgrade() call (sk_net_refcnt, ns_tracker) are not
accessed by any concurrent code path at this point.
v2:
- Corrected fixes tag
- check patch line wrap nits
- ai commentary nits
net/rds: Fix circular locking dependency in rds_tcp_tune
syzbot reported a circular locking dependency in rds_tcp_tune() where
sk_net_refcnt_upgrade() is called while holding the socket lock:
======================================================
WARNING: possible circular locking dependency detected
======================================================
kworker/u10:8/15040 is trying to acquire lock:
ffffffff8e9aaf80 (fs_reclaim){+.+.}-{0:0},
at: __kmalloc_cache_noprof+0x4b/0x6f0
but task is already holding lock:
ffff88805a3c1ce0 (k-sk_lock-AF_INET6){+.+.}-{0:0},
at: rds_tcp_tune+0xd7/0x930
The issue occurs because sk_net_refcnt_upgrade() performs memory
allocation (via get_net_track() -> ref_tracker_alloc()) while the
socket lock is held, creating a circular dependency with fs_reclaim.
Fix this by moving sk_net_refcnt_upgrade() outside the socket lock
critical section. This is safe because the fields modified by the
sk_net_refcnt_upgrade() call (sk_net_refcnt, ns_tracker) are not
accessed by any concurrent code path at this point.
v2:
- Corrected fixes tag
- check patch line wrap nits
- ai commentary nits
Metrics
Affected Vendors & Products
Advisories
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Fixes
Solution
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Workaround
No workaround given by the vendor.
References
History
Fri, 03 Apr 2026 14:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: net/rds: Fix circular locking dependency in rds_tcp_tune syzbot reported a circular locking dependency in rds_tcp_tune() where sk_net_refcnt_upgrade() is called while holding the socket lock: ====================================================== WARNING: possible circular locking dependency detected ====================================================== kworker/u10:8/15040 is trying to acquire lock: ffffffff8e9aaf80 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_cache_noprof+0x4b/0x6f0 but task is already holding lock: ffff88805a3c1ce0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: rds_tcp_tune+0xd7/0x930 The issue occurs because sk_net_refcnt_upgrade() performs memory allocation (via get_net_track() -> ref_tracker_alloc()) while the socket lock is held, creating a circular dependency with fs_reclaim. Fix this by moving sk_net_refcnt_upgrade() outside the socket lock critical section. This is safe because the fields modified by the sk_net_refcnt_upgrade() call (sk_net_refcnt, ns_tracker) are not accessed by any concurrent code path at this point. v2: - Corrected fixes tag - check patch line wrap nits - ai commentary nits | |
| Title | net/rds: Fix circular locking dependency in rds_tcp_tune | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
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MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-04-03T13:24:23.958Z
Reserved: 2026-01-13T15:37:46.014Z
Link: CVE-2026-23419
Vulnrichment
No data.
NVD
Status : Awaiting Analysis
Published: 2026-04-03T14:16:27.843
Modified: 2026-04-03T16:10:23.730
Link: CVE-2026-23419
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.