[PATCH BlueZ 1/4] shared/mgmt: Set MTU to UINT16_MAX
From: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date: 2021-09-22 21:34:06
From: Luiz Augusto von Dentz <redacted> This sets MTU of MGMT socket to UINT16_MAX since some commands may require more than the default size (e.g. Load LTKs). Fixes: https://github.com/bluez/bluez/issues/201 --- src/shared/mgmt.c | 46 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 40 insertions(+), 6 deletions(-)
diff --git a/src/shared/mgmt.c b/src/shared/mgmt.c
index b869fa6ef..cec8993e7 100644
--- a/src/shared/mgmt.c
+++ b/src/shared/mgmt.c@@ -42,6 +42,7 @@ struct mgmt { bool in_notify; void *buf; uint16_t len; + uint16_t mtu; mgmt_debug_func_t debug_callback; mgmt_destroy_func_t debug_destroy; void *debug_data;
@@ -380,6 +381,32 @@ static bool can_read_data(struct io *io, void *user_data) return true; } +static void mgmt_set_mtu(struct mgmt *mgmt) +{ + socklen_t len = 0; + + /* Check if kernel support BT_SNDMTU to read the current MTU set */ + if (getsockopt(mgmt->fd, SOL_BLUETOOTH, BT_SNDMTU, &mgmt->mtu, + &len) < 0) { + /* If BT_SNDMTU is not supported then MTU cannot be changed and + * MTU is fixed to HCI_MAX_ACL_SIZE. + */ + mgmt->mtu = HCI_MAX_ACL_SIZE; + return; + } + + if (mgmt->mtu < UINT16_MAX) { + uint16_t mtu = UINT16_MAX; + + /* Try increasing the MTU since some commands may go + * over HCI_MAX_ACL_SIZE (1024) + */ + if (!setsockopt(mgmt->fd, SOL_BLUETOOTH, BT_SNDMTU, &mtu, + sizeof(mtu))) + mgmt->mtu = mtu; + } +} + struct mgmt *mgmt_new(int fd) { struct mgmt *mgmt;
@@ -423,6 +450,8 @@ struct mgmt *mgmt_new(int fd) mgmt->writer_active = false; + mgmt_set_mtu(mgmt); + return mgmt_ref(mgmt); }
@@ -534,9 +563,9 @@ bool mgmt_set_close_on_unref(struct mgmt *mgmt, bool do_close) return true; } -static struct mgmt_request *create_request(uint16_t opcode, uint16_t index, - uint16_t length, const void *param, - mgmt_request_func_t callback, +static struct mgmt_request *create_request(struct mgmt *mgmt, uint16_t opcode, + uint16_t index, uint16_t length, + const void *param, mgmt_request_func_t callback, void *user_data, mgmt_destroy_func_t destroy) { struct mgmt_request *request;
@@ -548,6 +577,11 @@ static struct mgmt_request *create_request(uint16_t opcode, uint16_t index, if (length > 0 && !param) return NULL; + if (length > mgmt->mtu) { + printf("length %u > %u mgmt->mtu", length, mgmt->mtu); + return NULL; + } + request = new0(struct mgmt_request, 1); request->len = length + MGMT_HDR_SIZE; request->buf = malloc(request->len);
@@ -711,7 +745,7 @@ unsigned int mgmt_send(struct mgmt *mgmt, uint16_t opcode, uint16_t index, if (!mgmt) return 0; - request = create_request(opcode, index, length, param, + request = create_request(mgmt, opcode, index, length, param, callback, user_data, destroy); if (!request) return 0;
@@ -742,7 +776,7 @@ unsigned int mgmt_send_nowait(struct mgmt *mgmt, uint16_t opcode, uint16_t index if (!mgmt) return 0; - request = create_request(opcode, index, length, param, + request = create_request(mgmt, opcode, index, length, param, callback, user_data, destroy); if (!request) return 0;
@@ -768,7 +802,7 @@ unsigned int mgmt_reply(struct mgmt *mgmt, uint16_t opcode, uint16_t index, if (!mgmt) return 0; - request = create_request(opcode, index, length, param, + request = create_request(mgmt, opcode, index, length, param, callback, user_data, destroy); if (!request) return 0;
--
2.31.1