In the Linux kernel, the following vulnerability has been resolved:
regulator: core: regulator_lock_two() should test for EDEADLK not EDEADLOCK
Compare against -EDEADLK, which is what ww_mutex_lock() actually
returns and what every other deadlock check in this file already uses.
Function regulator_lock_two() acquires two regulators via
regulator_lock_nested() -> ww_mutex_lock(). On contention,
ww_mutex_lock() returns -EDEADLK, which is the caller's signal to drop
the lock it holds and retry the acquisition in the canonical order.
However, regulator_lock_two() tests the return value against -EDEADLOCK
rather than -EDEADLK. On most architectures, EDEADLK and EDEADLOCK are
the same value, so the comparison happens to be correct and the bug is
invisible. But on MIPS, SPARC, and PowerPC, those two errors have
different values. The test is wrong: a genuine -EDEADLK backoff no
longer matches -EDEADLOCK, so instead of unlocking and retrying, the
code falls into WARN_ON(ret) and returns with only one of the two
regulators locked.
In practice, this is a bug only on MIPS, because the regulator core is
not built or used on the other two platforms.
In general, EDEADLK is preferred over EDEADLOCK for new code.
regulator: core: regulator_lock_two() should test for EDEADLK not EDEADLOCK
Compare against -EDEADLK, which is what ww_mutex_lock() actually
returns and what every other deadlock check in this file already uses.
Function regulator_lock_two() acquires two regulators via
regulator_lock_nested() -> ww_mutex_lock(). On contention,
ww_mutex_lock() returns -EDEADLK, which is the caller's signal to drop
the lock it holds and retry the acquisition in the canonical order.
However, regulator_lock_two() tests the return value against -EDEADLOCK
rather than -EDEADLK. On most architectures, EDEADLK and EDEADLOCK are
the same value, so the comparison happens to be correct and the bug is
invisible. But on MIPS, SPARC, and PowerPC, those two errors have
different values. The test is wrong: a genuine -EDEADLK backoff no
longer matches -EDEADLOCK, so instead of unlocking and retrying, the
code falls into WARN_ON(ret) and returns with only one of the two
regulators locked.
In practice, this is a bug only on MIPS, because the regulator core is
not built or used on the other two platforms.
In general, EDEADLK is preferred over EDEADLOCK for new code.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Sat, 15 Aug 2026 06:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: regulator: core: regulator_lock_two() should test for EDEADLK not EDEADLOCK Compare against -EDEADLK, which is what ww_mutex_lock() actually returns and what every other deadlock check in this file already uses. Function regulator_lock_two() acquires two regulators via regulator_lock_nested() -> ww_mutex_lock(). On contention, ww_mutex_lock() returns -EDEADLK, which is the caller's signal to drop the lock it holds and retry the acquisition in the canonical order. However, regulator_lock_two() tests the return value against -EDEADLOCK rather than -EDEADLK. On most architectures, EDEADLK and EDEADLOCK are the same value, so the comparison happens to be correct and the bug is invisible. But on MIPS, SPARC, and PowerPC, those two errors have different values. The test is wrong: a genuine -EDEADLK backoff no longer matches -EDEADLOCK, so instead of unlocking and retrying, the code falls into WARN_ON(ret) and returns with only one of the two regulators locked. In practice, this is a bug only on MIPS, because the regulator core is not built or used on the other two platforms. In general, EDEADLK is preferred over EDEADLOCK for new code. | |
| Title | regulator: core: regulator_lock_two() should test for EDEADLK not EDEADLOCK | |
| 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: 2026-08-15T05:55:29.118Z
Reserved: 2026-08-09T03:40:39.918Z
Link: CVE-2026-72314
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-08-15T06:22:04.223
Modified: 2026-08-15T06:22:04.223
Link: CVE-2026-72314
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.