f2fs: potential shift wrapping buf in f2fs_trim_fs()

PATCH New Dan Carpenter 1 participant 1 message Sep 25, 2014

Subsystems (2)

Kernel janitors F2FS file system

lore

Share & tools

lore

Dan Carpenter

author

2014-09-25 11:39 UTC #0 lore raw

PATCH 1/1 f2fs: potential shift wrapping buf in f2fs_trim_fs()

My static checker complains that segment is a u64 but only the lower 31 bits can be used before we hit a shift wrapping bug.

Signed-off-by Dan Carpenter <[email protected]>

fs/f2fs/segment.c +1 -1

index b423005..d8ed1b8 100644
@@ -949,7 +949,7 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
 	block_t start_addr = SM_I(sbi)->main_blkaddr;
 	__u64 start = range->start >> sbi->log_blocksize;
 	__u64 end = start + (range->len >> sbi->log_blocksize) - 1;
-	__u64 segment = 1 << (sbi->log_blocksize + sbi->log_blocks_per_seg);
+	__u64 segment = 1ULL << (sbi->log_blocksize + sbi->log_blocks_per_seg);
 	unsigned int start_segno, end_segno;
 	struct cp_control cpc;