Commit 8744de7f authored Oct 21, 2014 by Jan Kara Committed by Greg Kroah-Hartman Jan 08, 2015

f2fs: avoid returning uninitialized value to userspace from f2fs_trim_fs()



commit 9bd27ae4aafc9bfee6c8791f7d801ea16cc5622b upstream.

If user specifies too low end sector for trimming, f2fs_trim_fs() will
use uninitialized value as a number of trimmed blocks and returns it to
userspace. Initialize number of trimmed blocks early to avoid the
problem.

Coverity-id: 1248809
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 83b12edd

fs/f2fs/segment.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1004,6 +1004,7 @@ int f2fs_trim_fs(struct f2fs_sb_info sbi, struct fstrim_range range)
		range->len < sbi->blocksize)
		return -EINVAL;

		cpc.trimmed = 0;
		if (end <= MAIN_BLKADDR(sbi))
		goto out;

		@@ -1015,7 +1016,6 @@ int f2fs_trim_fs(struct f2fs_sb_info sbi, struct fstrim_range range)
		cpc.trim_start = start_segno;
		cpc.trim_end = end_segno;
		cpc.trim_minlen = range->minlen >> sbi->log_blocksize;
		cpc.trimmed = 0;

		/* do checkpoint to issue discard commands safely */
		write_checkpoint(sbi, &cpc);