diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2018-06-16 15:40:48 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2018-09-25 23:47:28 +0100 |
| commit | 42a6cd12f1f0728e7c09a0c1dde8f6d9e8a5fbd6 (patch) | |
| tree | 9db0d686671b20e6c1b59f9a5b65d9f6d4b61c63 /fs | |
| parent | 177c48042c7120cdecb8ba782a2b82efdc373aa1 (diff) | |
ext4: never move the system.data xattr out of the inode body
commit 8cdb5240ec5928b20490a2bb34cb87e9a5f40226 upstream.
When expanding the extra isize space, we must never move the
system.data xattr out of the inode body. For performance reasons, it
doesn't make any sense, and the inline data implementation assumes
that system.data xattr is never in the external xattr block.
This addresses CVE-2018-10880
https://bugzilla.kernel.org/show_bug.cgi?id=200005
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/xattr.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index a62b732e49f8..00cd2e3b526b 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -1370,6 +1370,11 @@ retry: /* Find the entry best suited to be pushed into EA block */ entry = NULL; for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { + /* never move system.data out of the inode */ + if ((last->e_name_len == 4) && + (last->e_name_index == EXT4_XATTR_INDEX_SYSTEM) && + !memcmp(last->e_name, "data", 4)) + continue; total_size = EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + EXT4_XATTR_LEN(last->e_name_len); |