From: Andy Shevchenko Date: Mon, 10 Nov 2025 13:21:18 +0000 (+0100) Subject: lib/vsprintf: Check pointer before dereferencing in time_and_date() X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=372a12bd5df0199aa234eaf8ef31ed7ecd61d40f;p=thirdparty%2Flinux.git lib/vsprintf: Check pointer before dereferencing in time_and_date() 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 --- diff --git a/lib/vsprintf.c b/lib/vsprintf.c index e49f350ee549d..3f99834fd788f 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1928,9 +1928,6 @@ 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; @@ -1996,6 +1993,9 @@ 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);