CVE-2026-53090
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix ld_{abs,ind} failure path analysis in subprogs Usage of ld_{abs,ind} instructions got extended into subprogs some time ago via commit 09b28d76eac4 ("bpf: Add abnormal return checks."). These are only allowed in subprograms when the latter are BTF annotated and have scalar return types. The code generator in bpf_gen_ld_abs() has an abnormal exit path (r0=0 + exit) from legacy cBPF times. While the enforcement is on scalar return types, the verifier must also simulate the path of abnormal exit if the packet data load via ld_{abs,ind} failed. This is currently not the case. Fix it by having the verifier simulate both success and failure paths, and extend it in similar ways as we do for tail calls. The success path (r0=unknown, continue to next insn) is pushed onto stack for later validation and the r0=0 and return to the caller is done on the fall-through side.
취약점 유형
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix ld_{abs,ind} failure path analysis in subprogs Usage of ld_{abs,ind} instructions got extended into subprogs some time ago via commit 09b28d76eac4 ("bpf: Add abnormal return checks."). These are only allowed in subprograms when the latter are BTF annotated and have scalar return types. The code generator in bpf_gen_ld_abs() has an abnormal exit path (r0=0 + exit) from legacy cBPF times. While the enforcement is on scalar return types, the verifier must also simulate the path of abnormal exit if the packet data load via ld_{abs,ind} failed. This is currently not the case. Fix it by having the verifier simulate both success and failure paths, and extend it in similar ways as we do for tail calls. The success path (r0=unknown, continue to next insn) is pushed onto stack for later validation and the r0=0 and return to the caller is done on the fall-through side.
영향받는 제품
- linux linux_kernel
참고 자료
- https://git.kernel.org/stable/c/37ad2bb11e9de92cb7b94548705eeedd87f7d392
- https://git.kernel.org/stable/c/8674e2db06cff6b50f2216eed9a761d15425bb34
- https://git.kernel.org/stable/c/8a800497d9f6c2ec9c2c1ba7b71d0ac2ea7f7bbe
- https://git.kernel.org/stable/c/928d354ae3557e8f755a227e67be88034eb3cd7f
- https://git.kernel.org/stable/c/ce01a4e5cfac7adbe0be565f90cd32ecbb2f8337
- https://git.kernel.org/stable/c/d846d83bdacbd8f14fc45c63b8c1d22608452e1c
공격자보다 먼저 취약점을 찾으세요.
GitHub로 로그인하고 1분 안에 첫 감사를 실행하세요. 무료 플랜은 신용카드가 필요 없습니다.