From a3bb2d5587521eea6dab2d05326abb0afb460abd Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Sun, 30 Jul 2017 23:33:01 -0400 Subject: [PATCH] ext4: Don't clear SGID when inheriting ACLs 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@vger.kernel.org Signed-off-by: Theodore Ts'o Signed-off-by: Jan Kara Reviewed-by: Andreas Gruenbacher --- fs/ext4/acl.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c index 2985cd0a640d..46ff2229ff5e 100644 --- a/fs/ext4/acl.c +++ b/fs/ext4/acl.c @@ -189,18 +189,10 @@ __ext4_set_acl(handle_t *handle, struct inode *inode, int type, void *value = NULL; size_t size = 0; int error; - int update_mode = 0; - umode_t mode = inode->i_mode; switch (type) { case ACL_TYPE_ACCESS: name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS; - if (acl) { - error = posix_acl_update_mode(inode, &mode, &acl); - if (error) - return error; - update_mode = 1; - } break; case ACL_TYPE_DEFAULT: @@ -224,11 +216,6 @@ __ext4_set_acl(handle_t *handle, struct inode *inode, int type, kfree(value); if (!error) { set_cached_acl(inode, type, acl); - if (update_mode) { - inode->i_mode = mode; - inode->i_ctime = current_time(inode); - ext4_mark_inode_dirty(handle, inode); - } } return error; @@ -240,6 +227,8 @@ ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type) handle_t *handle; int error, credits, retries = 0; size_t acl_size = acl ? ext4_acl_size(acl->a_count) : 0; + umode_t mode = inode->i_mode; + int update_mode = 0; error = dquot_initialize(inode); if (error) @@ -254,7 +243,20 @@ retry: 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, 0 /* xattr_flags */); + if (!error && update_mode) { + inode->i_mode = mode; + inode->i_ctime = 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; -- 2.34.1