FAILED: patch "[PATCH] mm, slub: fix two bugs in slab_debug_trace_open()" failed to apply to 5.14-stable tree

The patch below does not apply to the 5.14-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 2127d22509aec3a83dffb2a3c736df7ba747a7ce Mon Sep 17 00:00:00 2001
From: Miaohe Lin <[email protected]>
Date: Mon, 18 Oct 2021 15:15:52 -0700
Subject: [PATCH] mm, slub: fix two bugs in slab_debug_trace_open()

Patch series "Fixups for slub".

This series contains various bug fixes for slub. We fix memoryleak, use-afer-free, NULL pointer dereferencing and so on in slub. More details can be found in the respective changelogs.

This patch (of 5):

It's possible that __seq_open_private() will return NULL. So we should check it before using lest dereferencing NULL pointer. And in error paths, we forgot to release private buffer via seq_release_private(). Memory will leak in these paths.

index 3d2025f7163b..ed160b6c54f8 100644
@@ -6108,9 +6108,14 @@ static int slab_debug_trace_open(struct inode *inode, struct file *filep)
 	struct kmem_cache *s = file_inode(filep)->i_private;
 	unsigned long *obj_map;
 
+	if (!t)
+		return -ENOMEM;
+
 	obj_map = bitmap_alloc(oo_objects(s->oo), GFP_KERNEL);
-	if (!obj_map)
+	if (!obj_map) {
+		seq_release_private(inode, filep);
 		return -ENOMEM;
+	}
 
 	if (strcmp(filep->f_path.dentry->d_name.name, "alloc_traces") == 0)
 		alloc = TRACK_ALLOC;

@@ -6119,6 +6124,7 @@ static int slab_debug_trace_open(struct inode *inode, struct file *filep)
 
 	if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL)) {
 		bitmap_free(obj_map);
+		seq_release_private(inode, filep);
 		return -ENOMEM;
 	}