diff options
| author | Mary Guillemard <mary.guillemard@collabora.com> | 2024-09-03 16:49:55 +0200 |
|---|---|---|
| committer | Boris Brezillon <boris.brezillon@collabora.com> | 2024-09-05 09:33:33 +0200 |
| commit | 5f7762042f8a5377bd8a32844db353c0311a7369 (patch) | |
| tree | 590b5bd8875bc131bbb4c6778f0834a138e0745a /drivers/gpu | |
| parent | 9a71cf8b6fa433a8f243626ba9930a3870584e38 (diff) | |
drm/panthor: Restrict high priorities on group_create
We were allowing any users to create a high priority group without any
permission checks. As a result, this was allowing possible denial of
service.
We now only allow the DRM master or users with the CAP_SYS_NICE
capability to set higher priorities than PANTHOR_GROUP_PRIORITY_MEDIUM.
As the sole user of that uAPI lives in Mesa and hardcode a value of
MEDIUM [1], this should be safe to do.
Additionally, as those checks are performed at the ioctl level,
panthor_group_create now only check for priority level validity.
[1]https://gitlab.freedesktop.org/mesa/mesa/-/blob/f390835074bdf162a63deb0311d1a6de527f9f89/src/gallium/drivers/panfrost/pan_csf.c#L1038
Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Cc: stable@vger.kernel.org
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240903144955.144278-2-mary.guillemard@collabora.com
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/panthor/panthor_drv.c | 23 | ||||
| -rw-r--r-- | drivers/gpu/drm/panthor/panthor_sched.c | 2 |
2 files changed, 24 insertions, 1 deletions
diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c index b5e7b919f241..34182f67136c 100644 --- a/drivers/gpu/drm/panthor/panthor_drv.c +++ b/drivers/gpu/drm/panthor/panthor_drv.c @@ -10,6 +10,7 @@ #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <drm/drm_auth.h> #include <drm/drm_debugfs.h> #include <drm/drm_drv.h> #include <drm/drm_exec.h> @@ -996,6 +997,24 @@ static int panthor_ioctl_group_destroy(struct drm_device *ddev, void *data, return panthor_group_destroy(pfile, args->group_handle); } +static int group_priority_permit(struct drm_file *file, + u8 priority) +{ + /* Ensure that priority is valid */ + if (priority > PANTHOR_GROUP_PRIORITY_HIGH) + return -EINVAL; + + /* Medium priority and below are always allowed */ + if (priority <= PANTHOR_GROUP_PRIORITY_MEDIUM) + return 0; + + /* Higher priorities require CAP_SYS_NICE or DRM_MASTER */ + if (capable(CAP_SYS_NICE) || drm_is_current_master(file)) + return 0; + + return -EACCES; +} + static int panthor_ioctl_group_create(struct drm_device *ddev, void *data, struct drm_file *file) { @@ -1011,6 +1030,10 @@ static int panthor_ioctl_group_create(struct drm_device *ddev, void *data, if (ret) return ret; + ret = group_priority_permit(file, args->priority); + if (ret) + return ret; + ret = panthor_group_create(pfile, args, queue_args); if (ret >= 0) { args->group_handle = ret; diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c index 463bcd3cf00f..12b272a912f8 100644 --- a/drivers/gpu/drm/panthor/panthor_sched.c +++ b/drivers/gpu/drm/panthor/panthor_sched.c @@ -3092,7 +3092,7 @@ int panthor_group_create(struct panthor_file *pfile, if (group_args->pad) return -EINVAL; - if (group_args->priority > PANTHOR_CSG_PRIORITY_HIGH) + if (group_args->priority >= PANTHOR_CSG_PRIORITY_COUNT) return -EINVAL; if ((group_args->compute_core_mask & ~ptdev->gpu_info.shader_present) || |