diff --git a/fs/xfs/libxfs/xfs_dir2_data.c b/fs/xfs/libxfs/xfs_dir2_data.c index ea0b9628df18..a16b05c43e2e 100644 --- a/fs/xfs/libxfs/xfs_dir2_data.c +++ b/fs/xfs/libxfs/xfs_dir2_data.c @@ -178,6 +178,14 @@ __xfs_dir3_data_check( while (offset < end) { struct xfs_dir2_data_unused *dup = bp->b_addr + offset; struct xfs_dir2_data_entry *dep = bp->b_addr + offset; + unsigned int reclen; + + /* + * Are the remaining bytes large enough to hold an + * unused entry? + */ + if (offset > end - xfs_dir2_data_unusedsize(1)) + return __this_address; /* * If it's unused, look for the space in the bestfree table. @@ -187,9 +195,13 @@ __xfs_dir3_data_check( if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { xfs_failaddr_t fa; + reclen = xfs_dir2_data_unusedsize( + be16_to_cpu(dup->length)); if (lastfree != 0) return __this_address; - if (offset + be16_to_cpu(dup->length) > end) + if (be16_to_cpu(dup->length) != reclen) + return __this_address; + if (offset + reclen > end) return __this_address; if (be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) != offset) @@ -207,10 +219,18 @@ __xfs_dir3_data_check( be16_to_cpu(bf[2].length)) return __this_address; } - offset += be16_to_cpu(dup->length); + offset += reclen; lastfree = 1; continue; } + + /* + * This is not an unused entry. Are the remaining bytes + * large enough for a dirent with a single-byte name? + */ + if (offset > end - xfs_dir2_data_entsize(mp, 1)) + return __this_address; + /* * It's a real entry. Validate the fields. * If this is a block directory then make sure it's @@ -219,9 +239,10 @@ __xfs_dir3_data_check( */ if (dep->namelen == 0) return __this_address; - if (!xfs_verify_dir_ino(mp, be64_to_cpu(dep->inumber))) + reclen = xfs_dir2_data_entsize(mp, dep->namelen); + if (offset + reclen > end) return __this_address; - if (offset + xfs_dir2_data_entsize(mp, dep->namelen) > end) + if (!xfs_verify_dir_ino(mp, be64_to_cpu(dep->inumber))) return __this_address; if (be16_to_cpu(*xfs_dir2_data_entry_tag_p(mp, dep)) != offset) return __this_address; @@ -245,7 +266,7 @@ __xfs_dir3_data_check( if (i >= be32_to_cpu(btp->count)) return __this_address; } - offset += xfs_dir2_data_entsize(mp, dep->namelen); + offset += reclen; } /* * Need to have seen all the entries and all the bestfree slots. diff --git a/fs/xfs/libxfs/xfs_dir2_priv.h b/fs/xfs/libxfs/xfs_dir2_priv.h index 3befb32509fa..10041350274a 100644 --- a/fs/xfs/libxfs/xfs_dir2_priv.h +++ b/fs/xfs/libxfs/xfs_dir2_priv.h @@ -189,6 +189,13 @@ void xfs_dir2_sf_put_ftype(struct xfs_mount *mp, extern int xfs_readdir(struct xfs_trans *tp, struct xfs_inode *dp, struct dir_context *ctx, size_t bufsize); +static inline unsigned int +xfs_dir2_data_unusedsize( + unsigned int len) +{ + return round_up(len, XFS_DIR2_DATA_ALIGN); +} + static inline unsigned int xfs_dir2_data_entsize( struct xfs_mount *mp,