CVE-2022-49085

Summary

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

drbd: Fix five use after free bugs in get_initial_state

In get_initial_state, it calls notify_initial_state_done(skb,..) if cb->args[5]==1. If genlmsg_put() failed in notify_initial_state_done(), the skb will be freed by nlmsg_free(skb). Then get_initial_state will goto out and the freed skb will be used by return value skb->len, which is a uaf bug.

What's worse, the same problem goes even further: skb can also be freed in the notify_state_change -> notify_state calls below. Thus 4 additional uaf bugs happened.

My patch lets the problem callee functions: notify_initial_state_done and notify_*_state_change return an error code if errors happen. So that the error codes could be propagated and the uaf bugs can be avoid.

v2 reports a compilation warning. This v3 fixed this warning and built successfully in my local environment with no additional warnings. v2: https://lore.kernel.org/patchwork/patch/1435218/

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < 0489700bfeb1e53eb2039c2291c67e71b0b40103affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < dcf6be17b5c53b741898d2223b23e66d682de300affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < 188fe6b26765edbad4055611c0f788b6870f4024affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < b6a4055036eed1f5e239ce3d8b0db1ce38bba447affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < 594205b4936771a250f9d141e7e0fff21c3dd2d9affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < a972c768723359ec995579902473028fe3cd64b1affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < de63e74da2333b4068bb79983e632db730fea97eaffected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < 226e993c39405292781bfcf4b039a8db56aab362affected
LinuxLinuxa29728463b254ce81ecefdf20c1a02e01d9361da < aadb22ba2f656581b2f733deb3a467c48cc618f6affected
LinuxLinux4.5affected
LinuxLinux0 < 4.5unaffected
LinuxLinux4.9.311 <= 4.9.*unaffected
LinuxLinux4.14.276 <= 4.14.*unaffected
LinuxLinux4.19.238 <= 4.19.*unaffected
LinuxLinux5.4.189 <= 5.4.*unaffected
LinuxLinux5.10.111 <= 5.10.*unaffected
LinuxLinux5.15.34 <= 5.15.*unaffected
LinuxLinux5.16.20 <= 5.16.*unaffected
LinuxLinux5.17.3 <= 5.17.*unaffected
LinuxLinux5.18 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

References