diff options
| author | Ben Hutchings <ben@decadent.org.uk> | 2017-10-08 16:48:44 +0300 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2017-10-12 17:28:07 +0300 |
| commit | ff8c7374e5b333918bed10a85eba73c39989843d (patch) | |
| tree | 54efc716109543aa387ce96bb0ef083ddb26d009 | |
| parent | f651969ce7668b24cdeffb5a1e73fc7d2ef382ef (diff) | |
| download | linux-ff8c7374e5b333918bed10a85eba73c39989843d.tar.xz | |
ext3: preserve i_mode if ext2_set_acl() fails
Based on Ernesto A. Fernández's fix for ext2 (commit fe26569eb919), from
which the following description is taken:
> When changing a file's acl mask, ext2_set_acl() will first set the group
> bits of i_mode to the value of the mask, and only then set the actual
> extended attribute representing the new acl.
>
> If the second part fails (due to lack of space, for example) and the file
> had no acl attribute to begin with, the system will from now on assume
> that the mask permission bits are actual group permission bits, potentially
> granting access to the wrong users.
>
> Prevent this by only changing the inode mode after the acl has been set.
Cc: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | fs/ext3/acl.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/fs/ext3/acl.c b/fs/ext3/acl.c index 5507381681b8..72e13c25e62a 100644 --- a/fs/ext3/acl.c +++ b/fs/ext3/acl.c @@ -227,19 +227,25 @@ ext3_set_acl(struct inode *inode, struct posix_acl *acl, int type) { handle_t *handle; int error, retries = 0; + int update_mode = 0; + umode_t mode = inode->i_mode; retry: handle = ext3_journal_start(inode, EXT3_DATA_TRANS_BLOCKS(inode->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); if (type == ACL_TYPE_ACCESS && acl) { - error = posix_acl_update_mode(inode, &inode->i_mode, &acl); + error = posix_acl_update_mode(inode, &mode, &acl); if (error) goto journal_stop; + update_mode = 1; + } + error = __ext3_set_acl(handle, inode, type, acl); + if (!error && update_mode) { + inode->i_mode = mode; inode->i_ctime = CURRENT_TIME_SEC; ext3_mark_inode_dirty(handle, inode); } - error = __ext3_set_acl(handle, inode, type, acl); journal_stop: ext3_journal_stop(handle); if (error == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) |