From: Pengpeng Hou <pengpeng@iscas.ac.cn> stable inclusion from stable-v6.6.136 commit feba4907c30284b6d1ec0b350320242d4f288fc9 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9232 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 4346be6577aaa04586167402ae87bbdbe32484a4 ] parse_probe_arg() accepts quoted immediate strings and passes the body after the opening quote to __parse_imm_string(). That helper currently computes strlen(str) and immediately dereferences str[len - 1], which underflows when the body is empty and not closed with double-quotation. Reject empty non-closed immediate strings before checking for the closing quote. Link: https://lore.kernel.org/all/20260401160315.88518-1-pengpeng@iscas.ac.cn/ Fixes: a42e3c4de964 ("tracing/probe: Add immediate string parameter support") Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Tengda Wu <wutengda2@huawei.com> --- kernel/trace/trace_probe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index b168d6dd0773..6a96b03aae62 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -886,7 +886,7 @@ static int __parse_imm_string(char *str, char **pbuf, int offs) { size_t len = strlen(str); - if (str[len - 1] != '"') { + if (!len || str[len - 1] != '"') { trace_probe_log_err(offs + len, IMMSTR_NO_CLOSE); return -EINVAL; } -- 2.34.1