CVE-2021-47324

Summary

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

watchdog: Fix possible use-after-free in wdt_startup()

This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free.

Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 63a3dc24bd053792f84cb4eef0168b1266202a02affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 862f2b5a7c38762ac9e369daefbf361a91aca685affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0ac50a76cf3cd63db000648b3b19f3f98b8aaa76affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < dc9403097be52d57a5c9c35efa9be79d166a78afaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 146cc288fb80c662c9c35e7bc58325d1ac0a7875affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a397cb4576fc2fc802562418b3a50b8f67d60d31affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b4ebf4a4692e84163a69444c70ad515de06e2259affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8adbbe6c86bb13e14f8a19e036ae5f4f5661fd90affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c08a6b31e4917034f0ed0cb457c3bb209576f542affected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux4.4.276 <= 4.4.*unaffected
LinuxLinux4.9.276 <= 4.9.*unaffected
LinuxLinux4.14.240 <= 4.14.*unaffected
LinuxLinux4.19.198 <= 4.19.*unaffected
LinuxLinux5.4.134 <= 5.4.*unaffected
LinuxLinux5.10.52 <= 5.10.*unaffected
LinuxLinux5.12.19 <= 5.12.*unaffected
LinuxLinux5.13.4 <= 5.13.*unaffected
LinuxLinux5.14 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

CVE Program Container

Additional References

References