On Wed, Oct 07, 2026 at 05:52:22AM +0000, Masami Hiramatsu wrote: > On Tue, 06 Oct 2026 20:47:17 -0700, Kyle Zeng <[email protected]> wrote: > > On Wed, Oct 07, 2026 at 03:44:20AM +0000, Masami Hiramatsu wrote: > > > On Tue, 06 Oct 2026 15:51:12 -0700, Kyle Zeng <[email protected]> wrote: > > > > perf_trace_event_perm() allows tracepoint counters that do not request > > > > PERF_SAMPLE_RAW without raw tracepoint permissions. A self-targeted, > > > > disabled event with exclude_kernel=1 can therefore reach the filter > > > > compiler even at perf_event_paranoid=2. > > > > > > > > The .function suffix accepts any field of sizeof(long) and resolves its > > > > operand through kallsyms_lookup_name() and > > > > kallsyms_lookup_size_offset(). > > > > The success or failure of a numeric filter discloses whether an address > > > > belongs to a known kernel symbol range. On x86-64 this can be used to > > > > recover the randomized kernel image base. A named filter also exposes > > > > the resolved symbol range through the counter when the tracepoint field > > > > is controlled by the caller, as with a syscall argument. > > > > > > > > Pass the filter's perf origin to the predicate parser and require > > > > perf_allow_tracepoint() before resolving a .function operand. This uses > > > > the same sysctl, initial-namespace capability and LSM policy as raw > > > > tracepoint access, and closes both the numeric and named-symbol oracles. > > > > Do not change ordinary perf counting filters or filters created through > > > > the separately controlled tracefs interfaces. > > > > > > Good catch! > > > > > > > > > > > Fixes: e6745a4da964 ("tracing: Add a way to filter function addresses > > > > to function names") > > > > Cc: [email protected] > > > > Assisted-by: Codex:gpt-6-astra > > > > > > nit: This should be > > > > > > Assisted-by: LLM > > > > Didn't know there was a change of convention. Should I send in a v2 or > > it will be picked up automatically? > > We can change the tag when picking up, so you don't need to resend it only > for tag update. But for this patch, please update according to Sashiko's > comment.
Thanks for the explanation. I just sent a v2: https://sashiko.dev/#/message/20261007050315.65139-1-kylebot%40openai.com Best, Kyle > > https://lore.kernel.org/all/[email protected]/ > > Thanks, > > > > > Thanks, > > Kyle > > > > > > > > > Signed-off-by: Kyle Zeng <[email protected]> > > > > > > Reviewed-by: Masami Hiramatsu (Google) <[email protected]> > > > > > > Thanks! > > > > > > > > > -- > > > Masami Hiramatsu (Google) <[email protected]> > > -- > Masami Hiramatsu (Google) <[email protected]>
