CVE-2021-47323

Summary

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

watchdog: sc520_wdt: Fix possible use-after-free in wdt_turnoff()

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 < 0015581a79bbf8e521f85dddb7d3e4a66b9f51d4affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b4565a8a2d6bffb05bfbec11399d261ec16fe373affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2aef07017fae21c3d8acea9656b10e3b9c0f1e04affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 522e75ed63f67e815d4ec0deace67df22d9ce78eaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7c56c5508dc20a6b133bc669fc34327a6711c24caffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a173e3b62cf6dd3c4a0a10c8a82eedfcae81a566affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b3c41ea5bc34d8c7b19e230d80e0e555c6f5057daffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f0feab82f6a0323f54d85e8b512a2be64f83648aaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 90b7c141132244e8e49a34a4c1e445cce33e07f4affected
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