6.12-stable review patch. If anyone has any objections, please let me know.
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From: Andy Shevchenko andriy.shevchenko@linux.intel.com
[ 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 andriy.shevchenko@linux.intel.com Reviewed-by: Petr Mladek pmladek@suse.com Link: https://patch.msgid.link/20251110132118.4113976-1-andriy.shevchenko@linux.in... Signed-off-by: Petr Mladek pmladek@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- lib/vsprintf.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index a69e71a1ca55e..511c55d7b3abf 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1860,9 +1860,6 @@ 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; @@ -1928,6 +1925,9 @@ 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);