Hi Pauli,
On Thu, Feb 23, 2023 at 9:29 AM Pauli Virtanen <pav@xxxxxx> wrote:
>
> The following ASAN crash is observed when media endpoint is unregistered
> (stopping sound server) while streaming from remote BAP client:
>
> ERROR: AddressSanitizer: heap-use-after-free on address 0x60b0000474d8
> READ of size 8 at 0x60b0000474d8 thread T0
> #0 0x7a27c6 in stream_set_state src/shared/bap.c:1227
> #1 0x7aff61 in remove_streams src/shared/bap.c:2483
> #2 0x71d2d0 in queue_foreach src/shared/queue.c:207
> #3 0x7b0152 in bt_bap_remove_pac src/shared/bap.c:2501
> #4 0x463cda in media_endpoint_destroy profiles/audio/media.c:179
> ...
> 0x60b0000474d8 is located 8 bytes inside of 112-byte region
> freed by thread T0 here:
> #0 0x7f93b12b9388 in __interceptor_free.part.0 (/lib64/libasan.so.8+0xb9388)
> #1 0x7a0504 in bap_stream_free src/shared/bap.c:972
> #2 0x7a0800 in bap_stream_detach src/shared/bap.c:989
> #3 0x7a26d1 in bap_stream_state_changed src/shared/bap.c:1208
> #4 0x7a2ab4 in stream_set_state src/shared/bap.c:1252
> #5 0x7ab18a in stream_release src/shared/bap.c:1985
> #6 0x7c6919 in bt_bap_stream_release src/shared/bap.c:4572
> #7 0x7aff50 in remove_streams src/shared/bap.c:2482
> ...
> previously allocated by thread T0 here:
> #0 0x7f93b12ba6af in __interceptor_malloc (/lib64/libasan.so.8+0xba6af)
> #1 0x71e9ae in util_malloc src/shared/util.c:43
> #2 0x79c2f5 in bap_stream_new src/shared/bap.c:766
> #3 0x7a4863 in ep_config src/shared/bap.c:1446
> #4 0x7a4f22 in ascs_config src/shared/bap.c:1481
> ...
>
> When stream->client is false, bt_bap_stream_release already sets the
> stream to idle and frees it.
>
> Fix the crash by not setting the state to idle for the second time,
> in this case.
> ---
>
> Notes:
> Resend, in case this was missed.
>
> Crash seen when testing BlueZ at commit 67395a3b357d.
> Also occurs on current BlueZ master branch.
>
> src/shared/bap.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/src/shared/bap.c b/src/shared/bap.c
> index f16ba1832..5601accde 100644
> --- a/src/shared/bap.c
> +++ b/src/shared/bap.c
> @@ -2480,8 +2480,11 @@ static void remove_streams(void *data, void *user_data)
>
> stream = queue_remove_if(bap->streams, match_stream_lpac, pac);
> if (stream) {
> + bool client = stream->client;
> +
> bt_bap_stream_release(stream, NULL, NULL);
> - stream_set_state(stream, BT_BAP_STREAM_STATE_IDLE);
> + if (client)
> + stream_set_state(stream, BT_BAP_STREAM_STATE_IDLE);
> }
> }
>
> --
> 2.39.2
How about we do this inside bt_bap_stream_release:
diff --git a/src/shared/bap.c b/src/shared/bap.c
index f16ba1832aaa..49c521b1d9eb 100644
--- a/src/shared/bap.c
+++ b/src/shared/bap.c
@@ -2479,10 +2479,8 @@ static void remove_streams(void *data, void *user_data)
struct bt_bap_stream *stream;
stream = queue_remove_if(bap->streams, match_stream_lpac, pac);
- if (stream) {
+ if (stream)
bt_bap_stream_release(stream, NULL, NULL);
- stream_set_state(stream, BT_BAP_STREAM_STATE_IDLE);
- }
}
bool bt_bap_remove_pac(struct bt_bap_pac *pac)
@@ -4590,6 +4588,10 @@ unsigned int bt_bap_stream_release(struct
bt_bap_stream *stream,
return 0;
}
+ /* Check if stream still attached, otherwise consider it released */
+ if (!queue_find(stream->bap, NULL, stream))
+ stream_set_state(stream, BT_BAP_STREAM_STATE_IDLE);
+
return req->id;
}
--
Luiz Augusto von Dentz
