This is a note to let you know that I've just added the patch titled
drm/amdgpu: fix amdgpu_cs_p1_user_fence
to the 5.15-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:
drm-amdgpu-fix-amdgpu_cs_p1_user_fence.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 35588314e963938dfdcdb792c9170108399377d6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@xxxxxxx>
Date: Fri, 25 Aug 2023 15:28:00 +0200
Subject: drm/amdgpu: fix amdgpu_cs_p1_user_fence
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From: Christian König <christian.koenig@xxxxxxx>
commit 35588314e963938dfdcdb792c9170108399377d6 upstream.
The offset is just 32bits here so this can potentially overflow if
somebody specifies a large value. Instead reduce the size to calculate
the last possible offset.
The error handling path incorrectly drops the reference to the user
fence BO resulting in potential reference count underflow.
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 20 +++++---------------
1 file changed, 5 insertions(+), 15 deletions(-)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -45,7 +45,6 @@ static int amdgpu_cs_user_fence_chunk(st
struct drm_gem_object *gobj;
struct amdgpu_bo *bo;
unsigned long size;
- int r;
gobj = drm_gem_object_lookup(p->filp, data->handle);
if (gobj == NULL)
@@ -60,23 +59,14 @@ static int amdgpu_cs_user_fence_chunk(st
drm_gem_object_put(gobj);
size = amdgpu_bo_size(bo);
- if (size != PAGE_SIZE || (data->offset + 8) > size) {
- r = -EINVAL;
- goto error_unref;
- }
-
- if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
- r = -EINVAL;
- goto error_unref;
- }
+ if (size != PAGE_SIZE || data->offset > (size - 8))
+ return -EINVAL;
- *offset = data->offset;
+ if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm))
+ return -EINVAL;
+ *offset = data->offset;
return 0;
-
-error_unref:
- amdgpu_bo_unref(&bo);
- return r;
}
static int amdgpu_cs_bo_handles_chunk(struct amdgpu_cs_parser *p,
Patches currently in stable-queue which might be from christian.koenig@xxxxxxx are
queue-5.15/drm-amdgpu-fix-amdgpu_cs_p1_user_fence.patch
