Description

In the Linux kernel, the following vulnerability has been resolved: rhashtable: Fix potential deadlock by moving schedule_work outside lock Move the hash table growth check and work scheduling outside the rht lock to prevent a possible circular locking dependency. The original implementation could trigger a lockdep warning due to a potential deadlock scenario involving nested locks between rhashtable bucket, rq lock, and dsq lock. By relocating the growth check and work scheduling after releasing the rth lock, we break this potential deadlock chain. This change expands the flexibility of rhashtable by removing restrictive locking that previously limited its use in scheduler and workqueue contexts. Import to say that this calls rht_grow_above_75(), which reads from struct rhashtable without holding the lock, if this is a problem, we can move the check to the lock, and schedule the workqueue after the lock. Modified so that atomic_inc is also moved outside of the bucket lock along with the growth above 75% check.

Weaknesses 1

Affected Products 2

References 3

• git.kernel.org https://git.kernel.org/stable/c/ced8ce3c83a7150c5f5d371a8c332d7bc7f9b66d
  Patch
• git.kernel.org https://git.kernel.org/stable/c/e1d3422c95f003eba241c176adfe593c33e8a8f6
  Patch
• git.kernel.org https://git.kernel.org/stable/c/eb2e58484b838fb4e777ee9721bb9e20e6ca971d
  Patch

Remediation

• git.kernel.org https://git.kernel.org/stable/c/ced8ce3c83a7150c5f5d371a8c332d7bc7f9b66d
  Patch
• git.kernel.org https://git.kernel.org/stable/c/e1d3422c95f003eba241c176adfe593c33e8a8f6
  Patch
• git.kernel.org https://git.kernel.org/stable/c/eb2e58484b838fb4e777ee9721bb9e20e6ca971d
  Patch