Merge "Fix a race condition when creating rfcomm servers" (4137d4a9) · Commits · e / os / android_packages_modules_Bluetooth

system/stack/btm/btm_int_types.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -363,6 +363,7 @@ typedef struct tBTM_CB {
		kBtmLogHistoryBufferSize);
		CHECK(history_ != nullptr);
		history_->Push(std::string("Initialized btm history"));
		btm_available_index = 1;
		}

		void Free() {
		@@ -396,6 +397,7 @@ typedef struct tBTM_CB {
		friend bool BTM_TryAllocateSCN(uint8_t scn);
		friend bool BTM_FreeSCN(uint8_t scn);
		uint8_t btm_scn[BTM_MAX_SCN_];
		uint8_t btm_available_index;
		} tBTM_CB;

		/* security action for L2CAP COC channels */

+16 −2

Original line number	Diff line number	Diff line
		@@ -32,17 +32,31 @@ extern tBTM_CB btm_cb;
		*
		******************************************************************************/
		uint8_t BTM_AllocateSCN(void) {
		uint8_t x;
		BTM_TRACE_DEBUG("BTM_AllocateSCN");

		// stack reserves scn 1 for HFP, HSP we still do the correct way
		for (x = 1; x < PORT_MAX_RFC_PORTS; x++) {
		for (uint8_t x = btm_cb.btm_available_index; x < PORT_MAX_RFC_PORTS; x++) {
		if (!btm_cb.btm_scn[x]) {
		btm_cb.btm_scn[x] = true;
		btm_cb.btm_available_index = (x + 1);
		return (x + 1);
		}
		}

		// In order to avoid OOB, btm_available_index must be less than or equal to
		// PORT_MAX_RFC_PORTS
		btm_cb.btm_available_index =
		std::min(btm_cb.btm_available_index, (uint8_t)PORT_MAX_RFC_PORTS);

		// If there's no empty SCN from _last_index to BTM_MAX_SCN.
		for (uint8_t y = 1; y < btm_cb.btm_available_index; y++) {
		if (!btm_cb.btm_scn[y]) {
		btm_cb.btm_scn[y] = true;
		btm_cb.btm_available_index = (y + 1);
		return (y + 1);
		}
		}

		return (0); /* No free ports */
		}