From 39d0d3bdf7bab3021a31e501172ac0f18947f9b3 Mon Sep 17 00:00:00 2001
From: Anna Schumaker <Anna.Schumaker@netapp.com>
Date: Mon, 5 Oct 2015 16:43:26 -0400
Subject: [PATCH] NFS: Fix a tracepoint NULL-pointer dereference

Running xfstest generic/013 with the tracepoint nfs:nfs4_open_file
enabled produces a NULL-pointer dereference when calculating fileid and
filehandle of the opened file.  Fix this by checking if state is NULL
before trying to use the inode pointer.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---
 fs/nfs/nfs4trace.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/nfs4trace.h b/fs/nfs/nfs4trace.h
index 28df12e..671cf68 100644
--- a/fs/nfs/nfs4trace.h
+++ b/fs/nfs/nfs4trace.h
@@ -409,7 +409,7 @@ DECLARE_EVENT_CLASS(nfs4_open_event,
            __entry->flags = flags;
            __entry->fmode = (__force unsigned int)ctx->mode;
            __entry->dev = ctx->dentry->d_sb->s_dev;
-           if (!IS_ERR(state))
+           if (!IS_ERR_OR_NULL(state))
                inode = state->inode;
            if (inode != NULL) {
                __entry->fileid = NFS_FILEID(inode);

https://github.com/torvalds/linux/commits?author=Anna.Schumaker@netapp.com