CVE-2026-90358 PUBLISHED

bpf, x86: Fix trampoline stack size for 128-bit arguments

Assigner: Linux
Reserved: 11.09.2026 Published: 17.09.2026 Updated: 17.09.2026

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

bpf, x86: Fix trampoline stack size for 128-bit arguments

btf_distill_func_proto() accepts a function argument up to 16 bytes, so a 128-bit scalar such as __int128 reaches the x86 trampoline with arg_size == 16. But the current implementation assumes an __int128 argument only needs one register, so the register save area is under-allocated and save_args() overwrites adjacent stack slots.

Compute the register count from arg_size for all arguments to fix it.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 to 4aed2346fa9b88d458eeb8c01123f3c07585a675 (excl.)
  • affected from a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 to 40f3bfbbb222b92278f3797614b70f68d46824ac (excl.)
  • affected from a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 to a6d7d7a253c550e74b0651897fe313c2f9b2301f (excl.)
  • affected from a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 to 814cba835ef648e0c5eb79505c96c0493b29eea6 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 6.1 is affected
  • unaffected from 0 to 6.1 (excl.)
  • unaffected from 6.12.110 to 6.12.* (incl.)
  • unaffected from 6.18.52 to 6.18.* (incl.)
  • unaffected from 7.2.6 to 7.2.* (incl.)
  • unaffected from 7.3-rc1 to * (incl.)

References