CVE-2021-47124

io_uring: fix link timeout refs

State: Published
Severity: 7.8 High
Published: Mar 15, 2024
Updated: Aug 5, 2026
Reserved: Mar 4, 2024

Description

In the Linux kernel, the following vulnerability has been resolved:

io_uring: fix link timeout refs

WARNING: CPU: 0 PID: 10242 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 RIP: 0010:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 Call Trace: __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] io_put_req fs/io_uring.c:2140 [inline] io_queue_linked_timeout fs/io_uring.c:6300 [inline] __io_queue_sqe+0xbef/0xec0 fs/io_uring.c:6354 io_submit_sqe fs/io_uring.c:6534 [inline] io_submit_sqes+0x2bbd/0x7c50 fs/io_uring.c:6660 __do_sys_io_uring_enter fs/io_uring.c:9240 [inline] __se_sys_io_uring_enter+0x256/0x1d60 fs/io_uring.c:9182

io_link_timeout_fn() should put only one reference of the linked timeout request, however in case of racing with the master request's completion first io_req_complete() puts one and then io_put_req_deferred() is called.

Scores

CVSS	Score	Vector	Source
3.1	7.8 High	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Linux

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	1c20e9040f49687ba2ccc2ffd4411351a6c2ebff to before 0b2a990e5d2f76d020cb840c456e6ec5f0c27530Affected 1c20e9040f49687ba2ccc2ffd4411351a6c2ebff to before 6f5d7a45f58d3abe3a936de1441b8d6318f978ffAffected 9ae1f8dd372e0e4c020b345cf9e09f519265e981 to before 876808dba2ff7509bdd7f230c4f374a0caf4f410Affected 9ae1f8dd372e0e4c020b345cf9e09f519265e981 to before ff4a96ba5c8f9b266706280ff8021d2ef3f17e86Affected 9ae1f8dd372e0e4c020b345cf9e09f519265e981 to before a298232ee6b9a1d5d732aa497ff8be0d45b5bd82Affected 567c81912cec641db75ac6cb64c63f8367c97d19Affected 5.10.26 to before 5.10.43Affected 5.10.26 to before 5.10.55Affected 5.11.6 to before 5.12Affected
LinuxLinux	5.12Affected before 5.12Not affected 5.10.43 through 5.10.Not affected 5.10.55 through 5.10.Not affected 5.12.10 through 5.12.Not affected 5.12.19 through 5.12.Not affected 5.13 and laterNot affected

Product

Versions

LinuxLinux

1c20e9040f49687ba2ccc2ffd4411351a6c2ebff to before 0b2a990e5d2f76d020cb840c456e6ec5f0c27530Affected
1c20e9040f49687ba2ccc2ffd4411351a6c2ebff to before 6f5d7a45f58d3abe3a936de1441b8d6318f978ffAffected
9ae1f8dd372e0e4c020b345cf9e09f519265e981 to before 876808dba2ff7509bdd7f230c4f374a0caf4f410Affected
9ae1f8dd372e0e4c020b345cf9e09f519265e981 to before ff4a96ba5c8f9b266706280ff8021d2ef3f17e86Affected
9ae1f8dd372e0e4c020b345cf9e09f519265e981 to before a298232ee6b9a1d5d732aa497ff8be0d45b5bd82Affected
567c81912cec641db75ac6cb64c63f8367c97d19Affected
5.10.26 to before 5.10.43Affected
5.10.26 to before 5.10.55Affected
5.11.6 to before 5.12Affected

LinuxLinux

5.12Affected
before 5.12Not affected
5.10.43 through 5.10.*Not affected
5.10.55 through 5.10.*Not affected
5.12.10 through 5.12.*Not affected
5.12.19 through 5.12.*Not affected
5.13 and laterNot affected

References

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