From cb8e1eef351b640cfdb1a753ef44494fbf59186d Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 14 Dec 2016 13:24:48 +0100 Subject: fs: Give dentry to inode_change_ok() instead of inode [ Upstream commit 31051c85b5e2aaaf6315f74c72a732673632a905 ] inode_change_ok() will be resposible for clearing capabilities and IMA extended attributes and as such will need dentry. Give it as an argument to inode_change_ok() instead of an inode. Also rename inode_change_ok() to setattr_prepare() to better relect that it does also some modifications in addition to checks. References: CVE-2015-1350 Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Philipp Hahn Signed-off-by: Sasha Levin --- fs/ext2/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ext2') diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index f460ae36d5b7..f08604366cb5 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1547,7 +1547,7 @@ int ext2_setattr(struct dentry *dentry, struct iattr *iattr) struct inode *inode = d_inode(dentry); int error; - error = inode_change_ok(inode, iattr); + error = setattr_prepare(dentry, iattr); if (error) return error; -- cgit v1.2.3 From 62fa696b7b435e93ed114dd6a23aa0881d7f81b9 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 14 Dec 2016 13:24:50 +0100 Subject: posix_acl: Clear SGID bit when setting file permissions [ Upstream commit 073931017b49d9458aa351605b43a7e34598caef ] 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 Reviewed-by: Jeff Layton Signed-off-by: Jan Kara Signed-off-by: Andreas Gruenbacher Signed-off-by: Philipp Hahn Signed-off-by: Sasha Levin --- fs/ext2/acl.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) (limited to 'fs/ext2') diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c index 27695e6f4e46..d6aeb84e90b6 100644 --- a/fs/ext2/acl.c +++ b/fs/ext2/acl.c @@ -193,15 +193,11 @@ ext2_set_acl(struct inode *inode, struct posix_acl *acl, int type) case ACL_TYPE_ACCESS: name_index = EXT2_XATTR_INDEX_POSIX_ACL_ACCESS; if (acl) { - error = posix_acl_equiv_mode(acl, &inode->i_mode); - if (error < 0) + error = posix_acl_update_mode(inode, &inode->i_mode, &acl); + if (error) return error; - else { - inode->i_ctime = CURRENT_TIME_SEC; - mark_inode_dirty(inode); - if (error == 0) - acl = NULL; - } + inode->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(inode); } break; -- cgit v1.2.3