From 3e764e8a055b49e2dd78e96b03e5ac48ef7ffc14 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Mon, 10 Nov 2025 14:21:18 +0100 Subject: [PATCH] lib/vsprintf: Check pointer before dereferencing in time_and_date() [ Upstream commit 372a12bd5df0199aa234eaf8ef31ed7ecd61d40f ] The pointer may be invalid when gets to the printf(). In particular the time_and_date() dereferencing it in some cases without checking. Move the check from rtc_str() to time_and_date() to cover all cases. Fixes: 7daac5b2fdf8 ("lib/vsprintf: Print time64_t in human readable format") Signed-off-by: Andy Shevchenko Reviewed-by: Petr Mladek Link: https://patch.msgid.link/20251110132118.4113976-1-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek Signed-off-by: Sasha Levin --- lib/vsprintf.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index e46eb93c115dd..fc1cf66fffdb3 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1889,9 +1889,6 @@ char *rtc_str(char *buf, char *end, const struct rtc_time *tm, bool found = true; int count = 2; - if (check_pointer(&buf, end, tm, spec)) - return buf; - switch (fmt[count]) { case 'd': have_t = false; @@ -1957,6 +1954,9 @@ static noinline_for_stack char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, const char *fmt) { + if (check_pointer(&buf, end, ptr, spec)) + return buf; + switch (fmt[1]) { case 'R': return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); -- 2.47.3