From f070e5ac9bc7de71c34402048ce5526dccbd347c Mon Sep 17 00:00:00 2001 From: "Ernesto A. Fernández" Date: Wed, 12 Jul 2017 06:55:35 -0300 Subject: jfs: preserve i_mode if __jfs_set_acl() fails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When changing a file's acl mask, __jfs_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. Signed-off-by: Ernesto A. Fernández Signed-off-by: Dave Kleikamp --- fs/jfs/acl.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'fs/jfs') diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c index 1be45c8d460d..2e71b6e7e646 100644 --- a/fs/jfs/acl.c +++ b/fs/jfs/acl.c @@ -108,19 +108,26 @@ int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type) { int rc; tid_t tid; + int update_mode = 0; + umode_t mode = inode->i_mode; tid = txBegin(inode->i_sb, 0); mutex_lock(&JFS_IP(inode)->commit_mutex); if (type == ACL_TYPE_ACCESS && acl) { - rc = posix_acl_update_mode(inode, &inode->i_mode, &acl); + rc = posix_acl_update_mode(inode, &mode, &acl); if (rc) goto end_tx; - inode->i_ctime = current_time(inode); - mark_inode_dirty(inode); + update_mode = 1; } rc = __jfs_set_acl(tid, inode, type, acl); - if (!rc) + if (!rc) { + if (update_mode) { + inode->i_mode = mode; + inode->i_ctime = current_time(inode); + mark_inode_dirty(inode); + } rc = txCommit(tid, 1, &inode, 0); + } end_tx: txEnd(tid); mutex_unlock(&JFS_IP(inode)->commit_mutex); -- cgit v1.2.3-59-g8ed1b