From af2873b2691291e165b3ee3f24b651433885537f Mon Sep 17 00:00:00 2001 From: Iulia Tanasescu Date: Mon, 27 May 2024 10:54:18 +0300 Subject: [PATCH] shared/bap: Fix potential stream access after free In bap_bcast_set_state, state->func might trigger the stream to be released, thus the stream would have been freed before reaching the switch. After calling stream->func, the stream reference should not be accessed anymore, apart from when the stream has not yet been released and those cases will be handled inside the switch. This commit also handles the case when stream ops might lead to a state machine that ends with stream release, so the stream should avoid being accessed after the ops are executed. --- src/shared/bap.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/src/shared/bap.c b/src/shared/bap.c index 1d9f59f21..ec54da341 100644 --- a/src/shared/bap.c +++ b/src/shared/bap.c @@ -2051,7 +2051,7 @@ static void bap_bcast_set_state(struct bt_bap_stream *stream, uint8_t state) } /* Post notification updates */ - switch (stream->state) { + switch (state) { case BT_ASCS_ASE_STATE_IDLE: if (stream->ops && stream->ops->detach) stream->ops->detach(stream); @@ -5293,6 +5293,7 @@ unsigned int bt_bap_stream_config(struct bt_bap_stream *stream, void *user_data) { unsigned int id; + struct bt_bap *bap; if (!bap_stream_valid(stream)) return 0; @@ -5303,9 +5304,11 @@ unsigned int bt_bap_stream_config(struct bt_bap_stream *stream, if (!bt_bap_ref_safe(stream->bap)) return 0; + bap = stream->bap; + id = stream->ops->config(stream, qos, data, func, user_data); - bt_bap_unref(stream->bap); + bt_bap_unref(bap); return id; } @@ -5565,6 +5568,7 @@ unsigned int bt_bap_stream_enable(struct bt_bap_stream *stream, void *user_data) { unsigned int id; + struct bt_bap *bap; if (!bap_stream_valid(stream)) return 0; @@ -5575,10 +5579,12 @@ unsigned int bt_bap_stream_enable(struct bt_bap_stream *stream, if (!bt_bap_ref_safe(stream->bap)) return 0; + bap = stream->bap; + id = stream->ops->enable(stream, enable_links, metadata, func, user_data); - bt_bap_unref(stream->bap); + bt_bap_unref(bap); return id; } @@ -5588,6 +5594,7 @@ unsigned int bt_bap_stream_start(struct bt_bap_stream *stream, void *user_data) { unsigned int id; + struct bt_bap *bap; if (!bap_stream_valid(stream)) return 0; @@ -5598,9 +5605,11 @@ unsigned int bt_bap_stream_start(struct bt_bap_stream *stream, if (!bt_bap_ref_safe(stream->bap)) return 0; + bap = stream->bap; + id = stream->ops->start(stream, func, user_data); - bt_bap_unref(stream->bap); + bt_bap_unref(bap); return id; } @@ -5611,6 +5620,7 @@ unsigned int bt_bap_stream_disable(struct bt_bap_stream *stream, void *user_data) { unsigned int id; + struct bt_bap *bap; if (!bap_stream_valid(stream)) return 0; @@ -5621,9 +5631,11 @@ unsigned int bt_bap_stream_disable(struct bt_bap_stream *stream, if (!bt_bap_ref_safe(stream->bap)) return 0; + bap = stream->bap; + id = stream->ops->disable(stream, disable_links, func, user_data); - bt_bap_unref(stream->bap); + bt_bap_unref(bap); return id; } -- 2.47.3