f2fs: Fix gcc9 error -Werror=maybe-uninitialized

The function grub_get_node_path() could return uninitialized offset with
level == 0 if the block is greater than direct_index + 2 * direct_blks +
2 * indirect_blks + dindirect_blks. The uninitialized offset is then used
by function grub_f2fs_get_block() because level == 0 is valid and
meaningful return to be processed.

The fix is to set level = -1 as return value by grub_get_node_path() to
signify an error that the input block cannot be handled. Any caller
should therefore check level is negative or not before processing the
output.

Reported-by: Neil MacLeod <neil@nmacleod.com>
Signed-off-by: Michael Chang <mchang@suse.com>
Tested-by: Neil MacLeod <neil@nmacleod.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Michael Chang 2019-05-17 17:00:19 +08:00 committed by Daniel Kiper
parent ce946603cf
commit a06b079a36
1 changed files with 6 additions and 1 deletions

View File

@ -702,7 +702,7 @@ grub_get_node_path (struct grub_f2fs_inode *inode, grub_uint32_t block,
grub_uint32_t dindirect_blks = indirect_blks * NIDS_PER_BLOCK;
grub_uint32_t direct_index = DEF_ADDRS_PER_INODE;
int n = 0;
int level = 0;
int level = -1;
if (inode->i_inline & F2FS_INLINE_XATTR)
direct_index -= F2FS_INLINE_XATTR_ADDRS;
@ -712,6 +712,7 @@ grub_get_node_path (struct grub_f2fs_inode *inode, grub_uint32_t block,
if (block < direct_index)
{
offset[n] = block;
level = 0;
goto got;
}
@ -860,6 +861,10 @@ grub_f2fs_get_block (grub_fshelp_node_t node, grub_disk_addr_t block_ofs)
int level, i;
level = grub_get_node_path (inode, block_ofs, offset, noffset);
if (level < 0)
return -1;
if (level == 0)
return grub_le_to_cpu32 (inode->i_addr[offset[0]]);