Skip to main content
cve.nowby Sazabi
← All vulnerabilities
CVE-2024-56631

scsi: sg: Fix slab-use-after-free read in sg_release()

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 3.17, 5.4.290, 5.10.234, 5.15.177, 6.1.127, and 2 more
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: total

Summary

In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Fix slab-use-after-free read in sg_release() Fix a use-after-free bug in sg_release(), detected by syzbot with KASAN: BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5838 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:912 sg_release+0x1f4/0x2e0 drivers/scsi/sg.c:407 In sg_release(), the function kref_put(&sfp->f_ref, sg_remove_sfp) is called before releasing the open_rel_lock mutex. The kref_put() call may decrement the reference count of sfp to zero, triggering its cleanup through sg_remove_sfp(). This cleanup includes scheduling deferred work via sg_remove_sfp_usercontext(), which ultimately frees sfp. After kref_put(), sg_release() continues to unlock open_rel_lock and may reference sfp or sdp. If sfp has already been freed, this results in a slab-use-after-free error. Move the kref_put(&sfp->f_ref, sg_remove_sfp) call after unlocking the open_rel_lock mutex. This ensures: • No references to sfp or sdp occur after the reference count is decremented. • Cleanup functions such as sg_remove_sfp() and sg_remove_sfp_usercontext() can safely execute without impacting the mutex handling in sg_release(). The fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures proper sequencing of resource cleanup and mutex operations, eliminating the risk of use-after-free errors in sg_release().

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: total

  3. Record last updated

Affected versions

  • Linux Linux

    From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in e19acb1926c4a1f30ee1ec84d8afba2d975bd534; From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in 285ce1f89f8d414e7eecab5ef5118cd512596318; From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in 198b89dd5a595ee3f96e5ce5c448b0484cd0e53c; From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in 275b8347e21ab8193e93223a8394a806e4ba8918; From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in 59b30afa578637169e2819536bb66459fdddc39d; From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in 1f5e2f1ca5875728fcf62bc1a054707444ab4960; From cc833acbee9db5ca8c6162b015b4c93863c6f821 · fixed in f10593ad9bc36921f623361c9e3dd96bd52d85ee; From 3.16.85 · fixed in 3.17

  • Linux Linux

    3.17

  • KernelLinux

    From 3.17.0 · fixed in 5.4.290; From 5.5.0 · fixed in 5.10.234; From 5.11.0 · fixed in 5.15.177; From 5.16.0 · fixed in 6.1.127; From 6.2.0 · fixed in 6.6.66; From 6.7.0 · fixed in 6.12.5

References 7

git.kernel.org