In the Linux kernel, the following vulnerability has been resolved:
net/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion
rds_ib_xmit_atomic() always programs a masked atomic opcode
(IB_WR_MASKED_ATOMIC_CMP_AND_SWP or IB_WR_MASKED_ATOMIC_FETCH_AND_ADD)
for every RDS atomic cmsg. But the completion-side switch in
rds_ib_send_unmap_op() only handles the non-masked opcodes, so a masked
atomic completion falls through to default and returns rm == NULL while
send->s_op is left set. rds_ib_send_cqe_handler() then dereferences the
NULL rm via rm->m_final_op, oopsing in softirq context. An unprivileged
AF_RDS sendmsg() of an atomic cmsg over an active RDS/IB connection
triggers it; on hardware that natively accepts masked atomics (mlx4,
mlx5) no extra setup is needed.
RDS/IB: rds_ib_send_unmap_op: unexpected opcode 0xd in WR!
Oops: general protection fault [#1] SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197]
RIP: rds_ib_send_cqe_handler+0x25c/0xb10 (net/rds/ib_send.c:282)
Call Trace:
<IRQ>
rds_ib_send_cqe_handler (net/rds/ib_send.c:282)
poll_scq (net/rds/ib_cm.c:274)
rds_ib_tasklet_fn_send (net/rds/ib_cm.c:294)
tasklet_action_common (kernel/softirq.c:943)
handle_softirqs (kernel/softirq.c:573)
run_ksoftirqd (kernel/softirq.c:479)
</IRQ>
Kernel panic - not syncing: Fatal exception in interrupt
Handle the masked atomic opcodes in the same case as the non-masked
ones: they map to the same struct rds_message.atomic union member, so
the existing container_of()/rds_ib_send_unmap_atomic() body is correct
for them.
References
Configurations
Configuration 1 (hide)
|
History
08 Jul 2026, 19:14
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://git.kernel.org/stable/c/0f22412a2f4fbbe0251c132abee045d15a90e5b6 - Patch | |
| References | () https://git.kernel.org/stable/c/0f7baa82a24813cdad0b06a6f8f07e4824af5ed5 - Patch | |
| References | () https://git.kernel.org/stable/c/34080db3e70ddf94c38512ad2331e3c3afca6cc1 - Patch | |
| References | () https://git.kernel.org/stable/c/4dd262f875e87653df50b138de1390ab0628e6b7 - Patch | |
| References | () https://git.kernel.org/stable/c/4fd34669558085bcb589aa2078a13b0ca79e360d - Patch | |
| References | () https://git.kernel.org/stable/c/6e4615164d185a26badb2f376a2449f4d174a5f0 - Patch | |
| References | () https://git.kernel.org/stable/c/a0148342badd8c9b2e46551766a27cb76c82e715 - Patch | |
| References | () https://git.kernel.org/stable/c/dcf458120add64c96a6ef5cf719340453f6e6abf - Patch | |
| First Time |
Linux linux Kernel
Linux |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| CWE | CWE-476 | |
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* |
24 Jun 2026, 08:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-06-24 08:16
Updated : 2026-07-08 19:14
NVD link : CVE-2026-52939
Mitre link : CVE-2026-52939
CVE.ORG link : CVE-2026-52939
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-476
NULL Pointer Dereference