On Sat, Mar 10, 2018 at 05:47:33PM -0500, Theodore Ts'o wrote:
> From: Lukas Czerner <lczerner@xxxxxxxxxx>
>
> Wrong directory block number can be saved in ->previous on big endian
> system in parse_int_node(). Fix it by moving the mask out of the endian
> conversion.
Thanks for the fix-up Ted. It looks good.
-Lukas
>
> Fixes: ae9efd05a986 ("e2fsck: 3 level hash tree directory optimization")
> Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
> ---
> e2fsck/pass2.c | 5 +++--
> lib/ext2fs/ext2_fs.h | 2 ++
> 2 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
> index 1b0504c85..e922876d3 100644
> --- a/e2fsck/pass2.c
> +++ b/e2fsck/pass2.c
> @@ -643,7 +643,7 @@ static void parse_int_node(ext2_filsys fs,
> printf("Entry #%d: Hash 0x%08x, block %u\n", i,
> hash, ext2fs_le32_to_cpu(ent[i].block));
> #endif
> - blk = ext2fs_le32_to_cpu(ent[i].block) & 0x0ffffff;
> + blk = ext2fs_le32_to_cpu(ent[i].block) & EXT4_DX_BLOCK_MASK;
> /* Check to make sure the block is valid */
> if (blk >= (blk_t) dx_dir->numblocks) {
> cd->pctx.blk = blk;
> @@ -664,7 +664,8 @@ static void parse_int_node(ext2_filsys fs,
> }
>
> dx_db->previous =
> - i ? ext2fs_le32_to_cpu(ent[i-1].block & 0x0ffffff) : 0;
> + i ? (ext2fs_le32_to_cpu(ent[i-1].block) &
> + EXT4_DX_BLOCK_MASK) : 0;
>
> if (hash < min_hash)
> min_hash = hash;
> diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
> index 2496d16da..7d6269413 100644
> --- a/lib/ext2fs/ext2_fs.h
> +++ b/lib/ext2fs/ext2_fs.h
> @@ -232,6 +232,8 @@ struct ext2_dx_root_info {
>
> #define EXT2_HASH_FLAG_INCOMPAT 0x1
>
> +#define EXT4_DX_BLOCK_MASK 0x0fffffff
> +
> struct ext2_dx_entry {
> __le32 hash;
> __le32 block;
> --
> 2.16.1.72.g5be1f00a9a
>
