f2fs: avoid returning uninitialized value to userspace from f2fs_trim_fs() 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 CC: [email protected] Signed-off-by: Jan Kara <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]>

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 2c1e608..6b08504 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c

@@ -1032,6 +1032,7 @@
 						range->len < sbi->blocksize)
 		return -EINVAL;
 
+	cpc.trimmed = 0;
 	if (end <= MAIN_BLKADDR(sbi))
 		goto out;
 
@@ -1043,7 +1044,6 @@
 	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);