CVE-2026-43376 (GCVE-0-2026-43376)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-05-08 14:21
VLAI?
Title
ksmbd: fix use-after-free by using call_rcu() for oplock_info
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free by using call_rcu() for oplock_info ksmbd currently frees oplock_info immediately using kfree(), even though it is accessed under RCU read-side critical sections in places like opinfo_get() and proc_show_files(). Since there is no RCU grace period delay between nullifying the pointer and freeing the memory, a reader can still access oplock_info structure after it has been freed. This can leads to a use-after-free especially in opinfo_get() where atomic_inc_not_zero() is called on already freed memory. Fix this by switching to deferred freeing using call_rcu().
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 296cb5457cc6f4a754c4ae29855f8a253d52bcc6 , < 302fef75512b2c8329a3f5efab1ae7ba2562387a (git)
Affected: d54ab1520d43e95f9b2e22d7a05fc9614192e5a5 , < 08aa9f3c8cf4d0bee44df540dfe34e8d64069f2c (git)
Affected: 18b4fac5ef17f77fed9417d22210ceafd6525fc7 , < 1d6abf145615dbfe267ce3b0a271f95e3780e18e (git)
Affected: 18b4fac5ef17f77fed9417d22210ceafd6525fc7 , < ce8507ee82c888126d8e7565e27c016308d24cde (git)
Affected: 18b4fac5ef17f77fed9417d22210ceafd6525fc7 , < 1dfd062caa165ec9d7ee0823087930f3ab8a6294 (git)
Affected: d73686367ad68534257cd88a36ca3c52cb8b81d8 (git)
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    Linux Linux Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 6.6.130 , ≤ 6.6.* (semver)
Unaffected: 6.12.78 , ≤ 6.12.* (semver)
Unaffected: 6.18.19 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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  }
}


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