From 497de07d89c1410d76a15bec2bb41f24a2a89f31 Mon Sep 17 00:00:00 2001 From: Gu Zheng Date: Mon, 9 Jan 2017 09:34:48 +0800 Subject: [PATCH] tmpfs: clear S_ISGID when setting posix ACLs This change was missed the tmpfs modification in In CVE-2016-7097 commit 073931017b49 ("posix_acl: Clear SGID bit when setting file permissions") It can test by xfstest generic/375, which failed to clear setgid bit in the following test case on tmpfs: touch $testfile chown 100:100 $testfile chmod 2755 $testfile _runas -u 100 -g 101 -- setfacl -m u::rwx,g::rwx,o::rwx $testfile Signed-off-by: Gu Zheng Signed-off-by: Al Viro --- fs/posix_acl.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 5955220..c9d48dc 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -922,11 +922,10 @@ int simple_set_acl(struct inode *inode, struct posix_acl *acl, int type) int error; if (type == ACL_TYPE_ACCESS) { - error = posix_acl_equiv_mode(acl, &inode->i_mode); - if (error < 0) - return 0; - if (error == 0) - acl = NULL; + error = posix_acl_update_mode(inode, + &inode->i_mode, &acl); + if (error) + return error; } inode->i_ctime = current_time(inode); -- 2.7.4