From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> [ Upstream commit 564277eceeca01e02b1ef3e141cfb939184601b4 ] January is month 1. There is no zero-th month. If someone passes a zero month then it means we read from one space before the start of the total_days_of_prev_months[] array. We may as well also be strict about days as well. Fixes: 1bd5bbcb6531 ("[CIFS] Legacy time handling for Win9x and OS/2 part 1") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Steve French <smfrench@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> --- fs/cifs/netmisc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/cifs/netmisc.c b/fs/cifs/netmisc.c index abae6dd2c6b9..cc88f4f0325e 100644 --- a/fs/cifs/netmisc.c +++ b/fs/cifs/netmisc.c @@ -980,10 +980,10 @@ struct timespec cnvrtDosUnixTm(__le16 le_date, __le16 le_time, int offset) cifs_dbg(VFS, "illegal hours %d\n", st->Hours); days = sd->Day; month = sd->Month; - if ((days > 31) || (month > 12)) { + if (days < 1 || days > 31 || month < 1 || month > 12) { cifs_dbg(VFS, "illegal date, month %d day: %d\n", month, days); - if (month > 12) - month = 12; + days = clamp(days, 1, 31); + month = clamp(month, 1, 12); } month -= 1; days += total_days_of_prev_months[month]; -- 2.14.1