* FAILED: patch "[PATCH] drm/dp_mst: Fix NULL deref in" failed to apply to 5.4-stable tree
@ 2023-10-27 12:21 gregkh
2023-10-30 11:29 ` [PATCH 5.4.y] drm/dp_mst: Fix NULL deref in get_mst_branch_device_by_guid_helper() Lukasz Majczak
0 siblings, 1 reply; 3+ messages in thread
From: gregkh @ 2023-10-27 12:21 UTC (permalink / raw)
To: lma, navaremanasi, rad, stable; +Cc: stable
The patch below does not apply to the 5.4-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 <stable@vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 3d887d512494d678b17c57b835c32f4e48d34f26
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023102723-steerable-trench-2f00@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3d887d512494d678b17c57b835c32f4e48d34f26 Mon Sep 17 00:00:00 2001
From: Lukasz Majczak <lma@semihalf.com>
Date: Fri, 22 Sep 2023 08:34:10 +0200
Subject: [PATCH] drm/dp_mst: Fix NULL deref in
get_mst_branch_device_by_guid_helper()
As drm_dp_get_mst_branch_device_by_guid() is called from
drm_dp_get_mst_branch_device_by_guid(), mstb parameter has to be checked,
otherwise NULL dereference may occur in the call to
the memcpy() and cause following:
[12579.365869] BUG: kernel NULL pointer dereference, address: 0000000000000049
[12579.365878] #PF: supervisor read access in kernel mode
[12579.365880] #PF: error_code(0x0000) - not-present page
[12579.365882] PGD 0 P4D 0
[12579.365887] Oops: 0000 [#1] PREEMPT SMP NOPTI
...
[12579.365895] Workqueue: events_long drm_dp_mst_up_req_work
[12579.365899] RIP: 0010:memcmp+0xb/0x29
[12579.365921] Call Trace:
[12579.365927] get_mst_branch_device_by_guid_helper+0x22/0x64
[12579.365930] drm_dp_mst_up_req_work+0x137/0x416
[12579.365933] process_one_work+0x1d0/0x419
[12579.365935] worker_thread+0x11a/0x289
[12579.365938] kthread+0x13e/0x14f
[12579.365941] ? process_one_work+0x419/0x419
[12579.365943] ? kthread_blkcg+0x31/0x31
[12579.365946] ret_from_fork+0x1f/0x30
As get_mst_branch_device_by_guid_helper() is recursive, moving condition
to the first line allow to remove a similar one for step over of NULL elements
inside a loop.
Fixes: 5e93b8208d3c ("drm/dp/mst: move GUID storage from mgr, port to only mst branch")
Cc: <stable@vger.kernel.org> # 4.14+
Signed-off-by: Lukasz Majczak <lma@semihalf.com>
Reviewed-by: Radoslaw Biernacki <rad@chromium.org>
Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230922063410.23626-1-lma@semihalf.com
diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index ed96cfcfa304..8c929ef72c72 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -2574,14 +2574,14 @@ static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
struct drm_dp_mst_branch *found_mstb;
struct drm_dp_mst_port *port;
+ if (!mstb)
+ return NULL;
+
if (memcmp(mstb->guid, guid, 16) == 0)
return mstb;
list_for_each_entry(port, &mstb->ports, next) {
- if (!port->mstb)
- continue;
-
found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
if (found_mstb)
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH 5.4.y] drm/dp_mst: Fix NULL deref in get_mst_branch_device_by_guid_helper()
2023-10-27 12:21 FAILED: patch "[PATCH] drm/dp_mst: Fix NULL deref in" failed to apply to 5.4-stable tree gregkh
@ 2023-10-30 11:29 ` Lukasz Majczak
2023-10-31 11:13 ` Greg KH
0 siblings, 1 reply; 3+ messages in thread
From: Lukasz Majczak @ 2023-10-30 11:29 UTC (permalink / raw)
To: stable; +Cc: Lukasz Majczak, Radoslaw Biernacki, Manasi Navare
As drm_dp_get_mst_branch_device_by_guid() is called from
drm_dp_get_mst_branch_device_by_guid(), mstb parameter has to be checked,
otherwise NULL dereference may occur in the call to
the memcpy() and cause following:
[12579.365869] BUG: kernel NULL pointer dereference, address: 0000000000000049
[12579.365878] #PF: supervisor read access in kernel mode
[12579.365880] #PF: error_code(0x0000) - not-present page
[12579.365882] PGD 0 P4D 0
[12579.365887] Oops: 0000 [#1] PREEMPT SMP NOPTI
...
[12579.365895] Workqueue: events_long drm_dp_mst_up_req_work
[12579.365899] RIP: 0010:memcmp+0xb/0x29
[12579.365921] Call Trace:
[12579.365927] get_mst_branch_device_by_guid_helper+0x22/0x64
[12579.365930] drm_dp_mst_up_req_work+0x137/0x416
[12579.365933] process_one_work+0x1d0/0x419
[12579.365935] worker_thread+0x11a/0x289
[12579.365938] kthread+0x13e/0x14f
[12579.365941] ? process_one_work+0x419/0x419
[12579.365943] ? kthread_blkcg+0x31/0x31
[12579.365946] ret_from_fork+0x1f/0x30
As get_mst_branch_device_by_guid_helper() is recursive, moving condition
to the first line allow to remove a similar one for step over of NULL elements
inside a loop.
Fixes: 5e93b8208d3c ("drm/dp/mst: move GUID storage from mgr, port to only mst branch")
Cc: <stable@vger.kernel.org> # 4.14+
Signed-off-by: Lukasz Majczak <lma@semihalf.com>
Reviewed-by: Radoslaw Biernacki <rad@chromium.org>
Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230922063410.23626-1-lma@semihalf.com
(cherry picked from commit 3d887d512494d678b17c57b835c32f4e48d34f26)
Signed-off-by: Lukasz Majczak <lma@semihalf.com>
---
drivers/gpu/drm/drm_dp_mst_topology.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 1ff13af13324..7b396b7277ee 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1806,14 +1806,14 @@ static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
struct drm_dp_mst_branch *found_mstb;
struct drm_dp_mst_port *port;
+ if (!mstb)
+ return NULL;
+
if (memcmp(mstb->guid, guid, 16) == 0)
return mstb;
list_for_each_entry(port, &mstb->ports, next) {
- if (!port->mstb)
- continue;
-
found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
if (found_mstb)
--
2.42.0.820.g83a721a137-goog
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH 5.4.y] drm/dp_mst: Fix NULL deref in get_mst_branch_device_by_guid_helper()
2023-10-30 11:29 ` [PATCH 5.4.y] drm/dp_mst: Fix NULL deref in get_mst_branch_device_by_guid_helper() Lukasz Majczak
@ 2023-10-31 11:13 ` Greg KH
0 siblings, 0 replies; 3+ messages in thread
From: Greg KH @ 2023-10-31 11:13 UTC (permalink / raw)
To: Lukasz Majczak; +Cc: stable, Radoslaw Biernacki, Manasi Navare
On Mon, Oct 30, 2023 at 12:29:04PM +0100, Lukasz Majczak wrote:
> As drm_dp_get_mst_branch_device_by_guid() is called from
> drm_dp_get_mst_branch_device_by_guid(), mstb parameter has to be checked,
> otherwise NULL dereference may occur in the call to
> the memcpy() and cause following:
>
> [12579.365869] BUG: kernel NULL pointer dereference, address: 0000000000000049
> [12579.365878] #PF: supervisor read access in kernel mode
> [12579.365880] #PF: error_code(0x0000) - not-present page
> [12579.365882] PGD 0 P4D 0
> [12579.365887] Oops: 0000 [#1] PREEMPT SMP NOPTI
> ...
> [12579.365895] Workqueue: events_long drm_dp_mst_up_req_work
> [12579.365899] RIP: 0010:memcmp+0xb/0x29
> [12579.365921] Call Trace:
> [12579.365927] get_mst_branch_device_by_guid_helper+0x22/0x64
> [12579.365930] drm_dp_mst_up_req_work+0x137/0x416
> [12579.365933] process_one_work+0x1d0/0x419
> [12579.365935] worker_thread+0x11a/0x289
> [12579.365938] kthread+0x13e/0x14f
> [12579.365941] ? process_one_work+0x419/0x419
> [12579.365943] ? kthread_blkcg+0x31/0x31
> [12579.365946] ret_from_fork+0x1f/0x30
>
> As get_mst_branch_device_by_guid_helper() is recursive, moving condition
> to the first line allow to remove a similar one for step over of NULL elements
> inside a loop.
>
> Fixes: 5e93b8208d3c ("drm/dp/mst: move GUID storage from mgr, port to only mst branch")
> Cc: <stable@vger.kernel.org> # 4.14+
> Signed-off-by: Lukasz Majczak <lma@semihalf.com>
> Reviewed-by: Radoslaw Biernacki <rad@chromium.org>
> Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
> Link: https://patchwork.freedesktop.org/patch/msgid/20230922063410.23626-1-lma@semihalf.com
> (cherry picked from commit 3d887d512494d678b17c57b835c32f4e48d34f26)
> Signed-off-by: Lukasz Majczak <lma@semihalf.com>
> ---
> drivers/gpu/drm/drm_dp_mst_topology.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
All now queued up, thanks.
greg k-h
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-10-31 11:13 UTC | newest]
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2023-10-27 12:21 FAILED: patch "[PATCH] drm/dp_mst: Fix NULL deref in" failed to apply to 5.4-stable tree gregkh
2023-10-30 11:29 ` [PATCH 5.4.y] drm/dp_mst: Fix NULL deref in get_mst_branch_device_by_guid_helper() Lukasz Majczak
2023-10-31 11:13 ` Greg KH
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