drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl

Userspace can race to free the gobj(robj converted from), robj should not
be accessed again after drm_gem_object_put, otherwith it will result in
use-after-free.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Min Li <lm0963hack@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Min Li 2023-06-03 15:43:45 +08:00 committed by Alex Deucher
parent 5a03159ab7
commit e6850f98ef
1 changed files with 1 additions and 3 deletions

View File

@ -459,7 +459,6 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data,
struct radeon_device *rdev = dev->dev_private; struct radeon_device *rdev = dev->dev_private;
struct drm_radeon_gem_set_domain *args = data; struct drm_radeon_gem_set_domain *args = data;
struct drm_gem_object *gobj; struct drm_gem_object *gobj;
struct radeon_bo *robj;
int r; int r;
/* for now if someone requests domain CPU - /* for now if someone requests domain CPU -
@ -472,13 +471,12 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data,
up_read(&rdev->exclusive_lock); up_read(&rdev->exclusive_lock);
return -ENOENT; return -ENOENT;
} }
robj = gem_to_radeon_bo(gobj);
r = radeon_gem_set_domain(gobj, args->read_domains, args->write_domain); r = radeon_gem_set_domain(gobj, args->read_domains, args->write_domain);
drm_gem_object_put(gobj); drm_gem_object_put(gobj);
up_read(&rdev->exclusive_lock); up_read(&rdev->exclusive_lock);
r = radeon_gem_handle_lockup(robj->rdev, r); r = radeon_gem_handle_lockup(rdev, r);
return r; return r;
} }