gfs2: incorrect check for debugfs returns
debugfs_create_dir and debugfs_create_file may return -ENODEV when debugfs
is not configured, so the return value should be checked against ERROR_VALUE
as well, otherwise the later dereference of the dentry pointer would crash
the kernel.
Signed-off-by: Chengyu Song <csong84@gatech.edu>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index f42dffb..0fa8062 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -2047,34 +2047,41 @@
int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
{
- sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
- if (!sdp->debugfs_dir)
- return -ENOMEM;
- sdp->debugfs_dentry_glocks = debugfs_create_file("glocks",
- S_IFREG | S_IRUGO,
- sdp->debugfs_dir, sdp,
- &gfs2_glocks_fops);
- if (!sdp->debugfs_dentry_glocks)
- goto fail;
+ struct dentry *dent;
- sdp->debugfs_dentry_glstats = debugfs_create_file("glstats",
- S_IFREG | S_IRUGO,
- sdp->debugfs_dir, sdp,
- &gfs2_glstats_fops);
- if (!sdp->debugfs_dentry_glstats)
+ dent = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
+ if (IS_ERR_OR_NULL(dent))
goto fail;
+ sdp->debugfs_dir = dent;
- sdp->debugfs_dentry_sbstats = debugfs_create_file("sbstats",
- S_IFREG | S_IRUGO,
- sdp->debugfs_dir, sdp,
- &gfs2_sbstats_fops);
- if (!sdp->debugfs_dentry_sbstats)
+ dent = debugfs_create_file("glocks",
+ S_IFREG | S_IRUGO,
+ sdp->debugfs_dir, sdp,
+ &gfs2_glocks_fops);
+ if (IS_ERR_OR_NULL(dent))
goto fail;
+ sdp->debugfs_dentry_glocks = dent;
+
+ dent = debugfs_create_file("glstats",
+ S_IFREG | S_IRUGO,
+ sdp->debugfs_dir, sdp,
+ &gfs2_glstats_fops);
+ if (IS_ERR_OR_NULL(dent))
+ goto fail;
+ sdp->debugfs_dentry_glstats = dent;
+
+ dent = debugfs_create_file("sbstats",
+ S_IFREG | S_IRUGO,
+ sdp->debugfs_dir, sdp,
+ &gfs2_sbstats_fops);
+ if (IS_ERR_OR_NULL(dent))
+ goto fail;
+ sdp->debugfs_dentry_sbstats = dent;
return 0;
fail:
gfs2_delete_debugfs_file(sdp);
- return -ENOMEM;
+ return dent ? PTR_ERR(dent) : -ENOMEM;
}
void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
@@ -2100,6 +2107,8 @@
int gfs2_register_debugfs(void)
{
gfs2_root = debugfs_create_dir("gfs2", NULL);
+ if (IS_ERR(gfs2_root))
+ return PTR_ERR(gfs2_root);
return gfs2_root ? 0 : -ENOMEM;
}