diff options
| author | Jan Kara <jack@suse.cz> | 2016-09-19 17:39:09 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-05-08 07:44:10 +0200 |
| commit | d8333c045f045385a914013a220cd1ed54c88d48 (patch) | |
| tree | 6f3354eeb66b4277f03d695b1c88d1d2f091f6c6 /fs/ocfs2 | |
| parent | 5a7b3b1ec16b6bfa57752d37292988e64fcdd172 (diff) | |
posix_acl: Clear SGID bit when setting file permissions
commit 073931017b49d9458aa351605b43a7e34598caef upstream.
When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok(). Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2). Fix that.
References: CVE-2016-7097
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ocfs2')
| -rw-r--r-- | fs/ocfs2/acl.c | 20 |
1 files changed, 8 insertions, 12 deletions
diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c index 8a7d2f812b5b..c7641f656494 100644 --- a/fs/ocfs2/acl.c +++ b/fs/ocfs2/acl.c @@ -241,20 +241,16 @@ int ocfs2_set_acl(handle_t *handle, case ACL_TYPE_ACCESS: name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS; if (acl) { - umode_t mode = inode->i_mode; - ret = posix_acl_equiv_mode(acl, &mode); - if (ret < 0) - return ret; - else { - if (ret == 0) - acl = NULL; + umode_t mode; - ret = ocfs2_acl_set_mode(inode, di_bh, - handle, mode); - if (ret) - return ret; + ret = posix_acl_update_mode(inode, &mode, &acl); + if (ret) + return ret; - } + ret = ocfs2_acl_set_mode(inode, di_bh, + handle, mode); + if (ret) + return ret; } break; case ACL_TYPE_DEFAULT: |