diff options
| author | Tvrtko Ursulin <tvrtko.ursulin@igalia.com> | 2025-06-10 17:42:23 +0100 |
|---|---|---|
| committer | Tvrtko Ursulin <tursulin@ursulin.net> | 2025-06-13 08:24:12 +0100 |
| commit | ad10976d6cf092a3ea5128d0bc5ab9318f71875f (patch) | |
| tree | 4768f8de71c883fb027d5b1a47dabf0af00a6c98 | |
| parent | a979a54165c224f3a469b59dcbd2e9754e7e0f41 (diff) | |
sync_file: Protect access to driver and timeline name
Protect the access to driver and timeline name which otherwise could be
freed as dma-fence exported is signalling fences.
This prepares the code for incoming dma-fence API changes which will start
asserting these accesses are done from a RCU locked section.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20250610164226.10817-2-tvrtko.ursulin@igalia.com
| -rw-r--r-- | drivers/dma-buf/sync_file.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c index 212df4b849fe..747e377fb954 100644 --- a/drivers/dma-buf/sync_file.c +++ b/drivers/dma-buf/sync_file.c @@ -135,12 +135,18 @@ char *sync_file_get_name(struct sync_file *sync_file, char *buf, int len) strscpy(buf, sync_file->user_name, len); } else { struct dma_fence *fence = sync_file->fence; + const char __rcu *timeline; + const char __rcu *driver; + rcu_read_lock(); + driver = dma_fence_driver_name(fence); + timeline = dma_fence_timeline_name(fence); snprintf(buf, len, "%s-%s%llu-%lld", - dma_fence_driver_name(fence), - dma_fence_timeline_name(fence), + rcu_dereference(driver), + rcu_dereference(timeline), fence->context, fence->seqno); + rcu_read_unlock(); } return buf; @@ -262,9 +268,17 @@ err_put_fd: static int sync_fill_fence_info(struct dma_fence *fence, struct sync_fence_info *info) { - strscpy(info->obj_name, dma_fence_timeline_name(fence), + const char __rcu *timeline; + const char __rcu *driver; + + rcu_read_lock(); + + driver = dma_fence_driver_name(fence); + timeline = dma_fence_timeline_name(fence); + + strscpy(info->obj_name, rcu_dereference(timeline), sizeof(info->obj_name)); - strscpy(info->driver_name, dma_fence_driver_name(fence), + strscpy(info->driver_name, rcu_dereference(driver), sizeof(info->driver_name)); info->status = dma_fence_get_status(fence); @@ -273,6 +287,8 @@ static int sync_fill_fence_info(struct dma_fence *fence, ktime_to_ns(dma_fence_timestamp(fence)) : ktime_set(0, 0); + rcu_read_unlock(); + return info->status; } |