CVE-2026-98383 PUBLISHED

bpf: Disallow bpf_skb_pull_data() for LWT_SEG6LOCAL

Assigner: Linux
Reserved: 25.09.2026 Published: 09.10.2026 Updated: 09.10.2026

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

bpf: Disallow bpf_skb_pull_data() for LWT_SEG6LOCAL

An LWT_SEG6LOCAL program can invalidate its cached SRH with bpf_lwt_seg6_adjust_srh() and then call bpf_skb_pull_data(). The latter may reallocate skb->head, leaving the per-CPU SRH pointer dangling. Post-program SRH validation then writes through that pointer.

Disallow bpf_skb_pull_data() for LWT_SEG6LOCAL programs so the verifier rejects this unsafe helper combination. Other LWT program types continue to expose the helper through lwt_out_func_proto().

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to 0f38472a2aa8704a6b514c0dfa9c32f3672b8f32 (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to cae8674489f26edf7553fdd660599466cbb4c32f (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to 9f9e57b5a3a033f95f49ef9d541340cdbcb80abb (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to df0072be6fc373cb22f9ea854d458b04e32a03cf (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to b9bb0e735460751b620156f800a4279a28573392 (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to 37b18688cd18fd86d2f35c212df1611862a26cd5 (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to fca71ead7a20290af1e2046983eeafae43d21af1 (excl.)
  • affected from 004d4b274e2a1a895a0e5dc66158b90a7d463d44 to e4a62833adff6ef0fe7c0b90393204fe3c26b5c5 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.18 is affected
  • unaffected from 0 to 4.18 (excl.)
  • unaffected from 5.10.271 to 5.10.* (incl.)
  • unaffected from 5.15.222 to 5.15.* (incl.)
  • unaffected from 6.1.189 to 6.1.* (incl.)
  • unaffected from 6.6.158 to 6.6.* (incl.)
  • unaffected from 6.12.112 to 6.12.* (incl.)
  • unaffected from 6.18.55 to 6.18.* (incl.)
  • unaffected from 7.2.9 to 7.2.* (incl.)
  • unaffected from 7.3-rc5 to * (incl.)

References