CVE-2022-48994

Summary

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

ALSA: seq: Fix function prototype mismatch in snd_seq_expand_var_event

With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), indirect call targets are validated against the expected function pointer prototype to make sure the call target is valid to help mitigate ROP attacks. If they are not identical, there is a failure at run time, which manifests as either a kernel panic or thread getting killed.

seq_copy_in_user() and seq_copy_in_kernel() did not have prototypes matching snd_seq_dump_func_t. Adjust this and remove the casts. There are not resulting binary output differences.

This was found as a result of Clang's new -Wcast-function-type-strict flag, which is more sensitive than the simpler -Wcast-function-type, which only checks for type width mismatches.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b38486e82ecb9f3046e0184205f6b61408fc40c9affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < e385360705a0b346bdb57ce938249175d0613b8aaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2f46e95bf344abc4e74f8158901d32a869e0adb6affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 63badfed200219ca656968725f1a43df293ac936affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 15c42ab8d43acb73e2eba361ad05822c0af0ecfaaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fccd454129f6a0739651f7f58307cdb631fd6e89affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 13ee8fb5410b740c8dd2867d3557c7662f7dda2daffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 05530ef7cf7c7d700f6753f058999b1b5099a026affected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux4.9.336 <= 4.9.*unaffected
LinuxLinux4.14.302 <= 4.14.*unaffected
LinuxLinux4.19.269 <= 4.19.*unaffected
LinuxLinux5.4.227 <= 5.4.*unaffected
LinuxLinux5.10.159 <= 5.10.*unaffected
LinuxLinux5.15.83 <= 5.15.*unaffected
LinuxLinux6.0.13 <= 6.0.*unaffected
LinuxLinux6.1 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

References