From: Jan Kara Date: Thu, 11 Aug 2016 15:58:32 +0000 (-0400) Subject: ext4: fix xattr shifting when expanding inodes part 2 X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=418c12d08dc64a45107c467ec1ba29b5e69b0715;p=linux.git ext4: fix xattr shifting when expanding inodes part 2 When multiple xattrs need to be moved out of inode, we did not properly recompute total size of xattr headers in the inode and the new header position. Thus when moving the second and further xattr we asked ext4_xattr_shift_entries() to move too much and from the wrong place, resulting in possible xattr value corruption or general memory corruption. CC: stable@vger.kernel.org # 4.4.x Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o --- diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index cb1d7b4482de7..b18b1ff7cc272 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -1516,6 +1516,7 @@ retry: error = ext4_xattr_ibody_set(handle, inode, &i, is); if (error) goto cleanup; + total_ino -= entry_size; entry = IFIRST(header); if (entry_size + EXT4_XATTR_SIZE(size) >= isize_diff) @@ -1526,11 +1527,11 @@ retry: ext4_xattr_shift_entries(entry, -shift_bytes, (void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE + EXT4_I(inode)->i_extra_isize + shift_bytes, - (void *)header, total_ino - entry_size, - inode->i_sb->s_blocksize); + (void *)header, total_ino, inode->i_sb->s_blocksize); isize_diff -= shift_bytes; EXT4_I(inode)->i_extra_isize += shift_bytes; + header = IHDR(inode, raw_inode); i.name = b_entry_name; i.value = buffer;