Commit 786534b92f3c introduced a regression that caused listxattr to
return the POSIX ACL attribute names even though sysfs doesn't support
POSIX ACLs. This happens because simple_xattr_list checks for NULL
i_acl / i_default_acl, but inode_init_always initializes those fields to
ACL_NOT_CACHED ((void *)-1). For example:
$ getfattr -m- -d /sys
/sys: system.posix_acl_access: Operation not supported
/sys: system.posix_acl_default: Operation not supported
Fix this in simple_xattr_list by checking if the filesystem supports
POSIX ACLs.
Fixes: 786534b92f3c ("tmpfs: listxattr should include POSIX ACL xattrs")
Reported-by: Marc Aurele La France <tsi@xxxxxxxxxx>
Tested-by: Marc Aurèle La France <tsi@xxxxxxxxxx>
Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
CC: Stable <stable@xxxxxxxxxxxxxxx> # v4.5+
---
fs/xattr.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/fs/xattr.c b/fs/xattr.c
index daa732550088..0d6a6a4af861 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -948,17 +948,19 @@ ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs,
int err = 0;
#ifdef CONFIG_FS_POSIX_ACL
- if (inode->i_acl) {
- err = xattr_list_one(&buffer, &remaining_size,
- XATTR_NAME_POSIX_ACL_ACCESS);
- if (err)
- return err;
- }
- if (inode->i_default_acl) {
- err = xattr_list_one(&buffer, &remaining_size,
- XATTR_NAME_POSIX_ACL_DEFAULT);
- if (err)
- return err;
+ if (IS_POSIXACL(inode)) {
+ if (inode->i_acl) {
+ err = xattr_list_one(&buffer, &remaining_size,
+ XATTR_NAME_POSIX_ACL_ACCESS);
+ if (err)
+ return err;
+ }
+ if (inode->i_default_acl) {
+ err = xattr_list_one(&buffer, &remaining_size,
+ XATTR_NAME_POSIX_ACL_DEFAULT);
+ if (err)
+ return err;
+ }
}
#endif
--
2.17.1
