CVE-2026-98062bpf: Mark signal tracepoint siginfo arguments as scalar

Official description

In the Linux kernel, the following vulnerability has been resolved: bpf: Mark signal tracepoint siginfo arguments as scalar The signal_generate and signal_deliver tracepoints declare their info argument as a struct kernel_siginfo pointer. btf_ctx_access() therefore treats it as a trusted pointer for tp_btf programs. Signal delivery also uses SEND_SIG_NOINFO and SEND_SIG_PRIV as special values for this argument. Those values are zero and one respectively, and are not pointers. A tp_btf program can currently dereference either value and fault the kernel. In particular, signal_generate can run from timer interrupt context, turning the fault into a kernel panic. Record both tracepoints in raw_tp_null_args[] and mark argument one as a non-pointer. This preserves scalar access to the cookie while rejecting direct and helper-mediated pointer use. Merely marking it nullable would not suffice because SEND_SIG_PRIV is nonzero.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/05757377fa0447163d07c43a119f81abe1eef8dc
• https://git.kernel.org/stable/c/0e78cb242a57e481061fcb542fed4d51afba25c4
• https://git.kernel.org/stable/c/d2eaea3599bcce659ce91862254dc91bcbdb6351
• https://git.kernel.org/stable/c/77515ab12e4983e6416f8c35039a3f0c0822ac70