From a513d86983164a1f74a226ab7006deffbf63907e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 20 Jan 2016 14:59:35 -0800 Subject: [PATCH] fat: allow time_offset to be up to 24 hours Currently we limit values of time_offset mount option to be between -12 and 12 hours. However e.g. zone GMT+12 can have a DST correction on top which makes the total time difference 13 hours. Update the checks in mount option parsing to allow offset of upto 24 hours to allow for unusual cases. Signed-off-by: Jan Kara Reported-by: Volker Kuhlmann Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/inode.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 6aece96df19f..3ac9078fde65 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -1146,7 +1146,12 @@ static int parse_options(struct super_block *sb, char *options, int is_vfat, case Opt_time_offset: if (match_int(&args[0], &option)) return -EINVAL; - if (option < -12 * 60 || option > 12 * 60) + /* + * GMT+-12 zones may have DST corrections so at least + * 13 hours difference is needed. Make the limit 24 + * just in case someone invents something unusual. + */ + if (option < -24 * 60 || option > 24 * 60) return -EINVAL; opts->tz_set = 1; opts->time_offset = option; -- 2.20.1