nfsd: Fix ACL null pointer deref
BugLink: http://bugs.launchpad.net/bugs/1348670
Fix regression introduced in pre-3.14 kernels by cherry-picking
aa07c713ecfc0522916f3cd57ac628ea6127c0ec
(NFSD: Call ->set_acl with a NULL ACL structure if no entries).
The affected code was removed in 3.14 by commit
4ac7249ea5a0ceef9f8269f63f33cc873c3fac61
(nfsd: use get_acl and ->set_acl).
The ->set_acl methods are already able to cope with a NULL argument.
Signed-off-by: Sergio Gelato <Sergio.Gelato@astro.su.se>
[bwh: Rewrite the subject]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Moritz Mühlenhoff <muehlenhoff@univention.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index d9b298c..81325ba 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -508,6 +508,9 @@
char *buf = NULL;
int error = 0;
+ if (!pacl)
+ return vfs_setxattr(dentry, key, NULL, 0, 0);
+
buflen = posix_acl_xattr_size(pacl->a_count);
buf = kmalloc(buflen, GFP_KERNEL);
error = -ENOMEM;