diff options
| author | Anton Vasilyev <vasilyev@ispras.ru> | 2018-07-27 18:30:58 +0300 |
|---|---|---|
| committer | Gerd Hoffmann <kraxel@redhat.com> | 2018-08-10 07:57:49 +0200 |
| commit | 66e0c8a5bcfd292606a70268376b44b468c316e8 (patch) | |
| tree | 5482dcf85ffae62d51eb03f32a978097da169220 /drivers/gpu/drm | |
| parent | 5043348a4969ae1661c008efe929abd0d76e3792 (diff) | |
drm: qxl: Fix NULL pointer dereference at qxl_alloc_client_monitors_config
If qxl_alloc_client_monitors_config() fails to allocate
client_monitors_config then NULL pointer dereference occurs
in function qxl_display_copy_rom_client_monitors_config() after
qxl_alloc_client_monitors_config() call.
The patch adds return error from qxl_alloc_client_monitors_config()
and additional status for qxl_display_copy_rom_client_monitors_config
return value.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
Link: http://patchwork.freedesktop.org/patch/msgid/20180727153058.23620-1-vasilyev@ispras.ru
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/qxl/qxl_display.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c index 0570c6826bff..01704a7f07cb 100644 --- a/drivers/gpu/drm/qxl/qxl_display.c +++ b/drivers/gpu/drm/qxl/qxl_display.c @@ -37,7 +37,8 @@ static bool qxl_head_enabled(struct qxl_head *head) return head->width && head->height; } -static void qxl_alloc_client_monitors_config(struct qxl_device *qdev, unsigned count) +static int qxl_alloc_client_monitors_config(struct qxl_device *qdev, + unsigned int count) { if (qdev->client_monitors_config && count > qdev->client_monitors_config->count) { @@ -49,15 +50,17 @@ static void qxl_alloc_client_monitors_config(struct qxl_device *qdev, unsigned c sizeof(struct qxl_monitors_config) + sizeof(struct qxl_head) * count, GFP_KERNEL); if (!qdev->client_monitors_config) - return; + return -ENOMEM; } qdev->client_monitors_config->count = count; + return 0; } enum { MONITORS_CONFIG_MODIFIED, MONITORS_CONFIG_UNCHANGED, MONITORS_CONFIG_BAD_CRC, + MONITORS_CONFIG_ERROR, }; static int qxl_display_copy_rom_client_monitors_config(struct qxl_device *qdev) @@ -87,7 +90,10 @@ static int qxl_display_copy_rom_client_monitors_config(struct qxl_device *qdev) && (num_monitors != qdev->client_monitors_config->count)) { status = MONITORS_CONFIG_MODIFIED; } - qxl_alloc_client_monitors_config(qdev, num_monitors); + if (qxl_alloc_client_monitors_config(qdev, num_monitors)) { + status = MONITORS_CONFIG_ERROR; + return status; + } /* we copy max from the client but it isn't used */ qdev->client_monitors_config->max_allowed = qdev->monitors_config->max_allowed; @@ -161,6 +167,10 @@ void qxl_display_read_client_monitors_config(struct qxl_device *qdev) break; udelay(5); } + if (status == MONITORS_CONFIG_ERROR) { + DRM_DEBUG_KMS("ignoring client monitors config: error"); + return; + } if (status == MONITORS_CONFIG_BAD_CRC) { DRM_DEBUG_KMS("ignoring client monitors config: bad crc"); return; |