This is a note to let you know that I've just added the patch titled

    dma-buf/dma-resv: Stop leaking on krealloc() failure

to the 6.1-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     dma-buf-dma-resv-stop-leaking-on-krealloc-failure.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <sta...@vger.kernel.org> know about it.


>From 05abb3be91d8788328231ee02973ab3d47f5e3d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrj...@linux.intel.com>
Date: Thu, 13 Jul 2023 22:47:45 +0300
Subject: dma-buf/dma-resv: Stop leaking on krealloc() failure
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Ville Syrjälä <ville.syrj...@linux.intel.com>

commit 05abb3be91d8788328231ee02973ab3d47f5e3d2 upstream.

Currently dma_resv_get_fences() will leak the previously
allocated array if the fence iteration got restarted and
the krealloc_array() fails.

Free the old array by hand, and make sure we still clear
the returned *fences so the caller won't end up accessing
freed memory. Some (but not all) of the callers of
dma_resv_get_fences() seem to still trawl through the
array even when dma_resv_get_fences() failed. And let's
zero out *num_fences as well for good measure.

Cc: Sumit Semwal <sumit.sem...@linaro.org>
Cc: Christian König <christian.koe...@amd.com>
Cc: linux-me...@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-...@lists.linaro.org
Fixes: d3c80698c9f5 ("dma-buf: use new iterator in dma_resv_get_fences v3")
Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
Reviewed-by: Christian König <christian.koe...@amd.com>
Cc: sta...@vger.kernel.org
Link: 
https://patchwork.freedesktop.org/patch/msgid/20230713194745.1751-1-ville.syrj...@linux.intel.com
Signed-off-by: Christian König <christian.koe...@amd.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/dma-buf/dma-resv.c |   13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

--- a/drivers/dma-buf/dma-resv.c
+++ b/drivers/dma-buf/dma-resv.c
@@ -566,6 +566,7 @@ int dma_resv_get_fences(struct dma_resv
        dma_resv_for_each_fence_unlocked(&cursor, fence) {
 
                if (dma_resv_iter_is_restarted(&cursor)) {
+                       struct dma_fence **new_fences;
                        unsigned int count;
 
                        while (*num_fences)
@@ -574,13 +575,17 @@ int dma_resv_get_fences(struct dma_resv
                        count = cursor.num_fences + 1;
 
                        /* Eventually re-allocate the array */
-                       *fences = krealloc_array(*fences, count,
-                                                sizeof(void *),
-                                                GFP_KERNEL);
-                       if (count && !*fences) {
+                       new_fences = krealloc_array(*fences, count,
+                                                   sizeof(void *),
+                                                   GFP_KERNEL);
+                       if (count && !new_fences) {
+                               kfree(*fences);
+                               *fences = NULL;
+                               *num_fences = 0;
                                dma_resv_iter_end(&cursor);
                                return -ENOMEM;
                        }
+                       *fences = new_fences;
                }
 
                (*fences)[(*num_fences)++] = dma_fence_get(fence);


Patches currently in stable-queue which might be from 
ville.syrj...@linux.intel.com are

queue-6.1/dma-buf-dma-resv-stop-leaking-on-krealloc-failure.patch

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