nfsd: fix buffer overrun decoding NFSv4 acl

commit 91b80969 upstream

The array we kmalloc() here is not large enough.

Thanks to Johann Dahm and David Richter for bug report and testing.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: David Richter <richterd@citi.umich.edu>
Tested-by: Johann Dahm <jdahm@umich.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

fs/nfsd/nfs4acl.c

@@ -443,7 +443,7 @@ init_state(struct posix_acl_state *state, int cnt)
 	 * enough space for either:
 	 */
 	alloc = sizeof(struct posix_ace_state_array)
-		+ cnt*sizeof(struct posix_ace_state);
+		+ cnt*sizeof(struct posix_user_ace_state);
 	state->users = kzalloc(alloc, GFP_KERNEL);
 	if (!state->users)
 		return -ENOMEM;