f2fs: fix incorrect mapping in ->bmap (43473f96) · Commits · 戴 / test

Currently, generic_block_bmap is used in f2fs_bmap, its semantics is when the mapping is been found, return position of target physical block, otherwise return zero. But, previously, when there is no mapping info for specified logical block, f2fs_bmap will map target physical block to a uninitialized variable, which should be wrong. Fix it. Signed-off-by:

Chao Yu <yuchao0@huawei.com> Signed-off-by:

Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/data.c

+7 −4

Original line number	Diff line number	Diff line
		@@ -648,6 +648,8 @@ next_dnode:
		set_new_dnode(&dn, inode, NULL, NULL, 0);
		err = get_dnode_of_data(&dn, pgofs, mode);
		if (err) {
		if (flag == F2FS_GET_BLOCK_BMAP)
		map->m_pblk = 0;
		if (err == -ENOENT) {
		err = 0;
		if (map->m_next_pgofs)
		@@ -683,19 +685,20 @@ next_block:
		map->m_flags = F2FS_MAP_NEW;
		blkaddr = dn.data_blkaddr;
		} else {
		if (flag == F2FS_GET_BLOCK_BMAP) {
		map->m_pblk = 0;
		goto sync_out;
		}
		if (flag == F2FS_GET_BLOCK_FIEMAP &&
		blkaddr == NULL_ADDR) {
		if (map->m_next_pgofs)
		*map->m_next_pgofs = pgofs + 1;
		}
		if (flag != F2FS_GET_BLOCK_FIEMAP \|\|
		blkaddr != NEW_ADDR) {
		if (flag == F2FS_GET_BLOCK_BMAP)
		err = -ENOENT;
		blkaddr != NEW_ADDR)
		goto sync_out;
		}
		}
		}

		if (map->m_len == 0) {
		/* preallocated unwritten block should be mapped for fiemap. */

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