On Sat, Oct 07, 2017 at 10:15:03PM -0400, Theodore Ts'o wrote:
> The upstream commit didn't apply cleanly into the LTS kernel trees, so
> the patch was dropped. The following backport will apply into the
> 3.18, 4.1, 4.4, and 4.9 LTS kernel trees.
>
> I've verified that it fixes xfstests generic/444.
The earlier patch I sent doesn't work some of the older LTS kernels.
Here is a corrected patch which is more portable to all LTS kernels.
It uses ext4_current_time() instead of current_time().
- Ted
>From 7319023a1a941bd76222d7742d3921c24b36a382 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@xxxxxxx>
Date: Sun, 30 Jul 2017 23:33:01 -0400
Subject: [PATCH] ext4: Don't clear SGID when inheriting ACLs
[ Upstream commit: a3bb2d5587521eea6dab2d05326abb0afb460abd ]
When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.
Fix the problem by moving posix_acl_update_mode() out of
__ext4_set_acl() into ext4_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.
Fixes: 073931017b49d9458aa351605b43a7e34598caef
CC: stable@xxxxxxxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
---
fs/ext4/acl.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)
diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index dfa519979038..dfd01ca1a60a 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -192,13 +192,6 @@ __ext4_set_acl(handle_t *handle, struct inode *inode, int type,
switch (type) {
case ACL_TYPE_ACCESS:
name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS;
- if (acl) {
- error = posix_acl_update_mode(inode, &inode->i_mode, &acl);
- if (error)
- return error;
- inode->i_ctime = ext4_current_time(inode);
- ext4_mark_inode_dirty(handle, inode);
- }
break;
case ACL_TYPE_DEFAULT:
@@ -231,6 +224,8 @@ ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
handle_t *handle;
int error, retries = 0;
+ umode_t mode = inode->i_mode;
+ int update_mode = 0;
retry:
handle = ext4_journal_start(inode, EXT4_HT_XATTR,
@@ -238,7 +233,20 @@ ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type)
if (IS_ERR(handle))
return PTR_ERR(handle);
+ if ((type == ACL_TYPE_ACCESS) && acl) {
+ error = posix_acl_update_mode(inode, &mode, &acl);
+ if (error)
+ goto out_stop;
+ update_mode = 1;
+ }
+
error = __ext4_set_acl(handle, inode, type, acl);
+ if (!error && update_mode) {
+ inode->i_mode = mode;
+ inode->i_ctime = ext4_current_time(inode);
+ ext4_mark_inode_dirty(handle, inode);
+ }
+out_stop:
ext4_journal_stop(handle);
if (error == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
goto retry;
--
2.11.0.rc0.7.gbe5a750