From c47a7b11bcb3d45e29723afcf6336866476b1d08 Mon Sep 17 00:00:00 2001 From: Taeyang Lee <0wn@theori.io> Date: Fri, 16 Oct 2026 02:19:55 +0900 Subject: [PATCH] tracing: Check operator stack capacity before pushing predicate_parse() uses the first operator stack entry before processing any opening parentheses. A push then increments top before writing. The existing check still permits that write when top already points to the last allocated entry, which can access beyond the operator stack. Reject the push when top reaches the last allocated entry. Cc: stable@vger.kernel.org Fixes: 39f7c41c908b ("tracing/filters: Enable filtering a cpumask field by another cpumask") Link: https://patch.msgid.link/atELO9L0I9kg5CpC@Taeyangs-MacBook-Pro.local Signed-off-by: Taeyang Lee <0wn@theori.io> Signed-off-by: Steven Rostedt --- kernel/trace/trace_events_filter.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 781416ba6bdf..127880ebe83f 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -511,7 +511,7 @@ predicate_parse(const char *str, int nr_parens, int nr_preds, switch (*next) { case '(': /* #2 */ - if (top - op_stack > nr_parens) { + if (top - op_stack >= nr_parens - 1) { ret = -EINVAL; goto out_free; }