mirror of
https://github.com/Divested-Mobile/DivestOS-Build.git
synced 2024-10-01 01:35:54 -04:00
116 lines
3.5 KiB
Diff
116 lines
3.5 KiB
Diff
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
|
From: Hui Peng <phui@google.com>
|
|
Date: Fri, 15 Dec 2023 22:55:33 +0000
|
|
Subject: [PATCH] Reland: Fix an OOB write bug in attp_build_value_cmd
|
|
|
|
This is a backport of I291fd665a68d90813b8c21c80d23cc438f84f285
|
|
|
|
Bug: 295887535
|
|
Bug: 315127634
|
|
Test: m com.android.btservices
|
|
Test: atest net_test_stack_gatt
|
|
Ignore-AOSP-First: security
|
|
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:70f7ff2b34e6683301c9c6cd021e1ddef76c5b1c)
|
|
Merged-In: Ieffac6db5c6359b071efc599f7a70de609b80b72
|
|
Change-Id: Ieffac6db5c6359b071efc599f7a70de609b80b72
|
|
---
|
|
stack/gatt/att_protocol.cc | 56 ++++++++++++++++++++++++++++++--------
|
|
1 file changed, 45 insertions(+), 11 deletions(-)
|
|
|
|
diff --git a/stack/gatt/att_protocol.cc b/stack/gatt/att_protocol.cc
|
|
index cdf472e40..aaf1a53a3 100644
|
|
--- a/stack/gatt/att_protocol.cc
|
|
+++ b/stack/gatt/att_protocol.cc
|
|
@@ -278,46 +278,80 @@ BT_HDR* attp_build_opcode_cmd(uint8_t op_code) {
|
|
BT_HDR* attp_build_value_cmd(uint16_t payload_size, uint8_t op_code,
|
|
uint16_t handle, uint16_t offset, uint16_t len,
|
|
uint8_t* p_data) {
|
|
- uint8_t *p, *pp, pair_len, *p_pair_len;
|
|
+ uint8_t *p, *pp, *p_pair_len;
|
|
+ size_t pair_len;
|
|
+ size_t size_now = 1;
|
|
+
|
|
+#define CHECK_SIZE() \
|
|
+ do { \
|
|
+ if (size_now > payload_size) { \
|
|
+ LOG(ERROR) << "payload size too small"; \
|
|
+ osi_free(p_buf); \
|
|
+ return nullptr; \
|
|
+ } \
|
|
+ } while (false)
|
|
+
|
|
BT_HDR* p_buf =
|
|
(BT_HDR*)osi_malloc(sizeof(BT_HDR) + payload_size + L2CAP_MIN_OFFSET);
|
|
|
|
p = pp = (uint8_t*)(p_buf + 1) + L2CAP_MIN_OFFSET;
|
|
+
|
|
+ CHECK_SIZE();
|
|
UINT8_TO_STREAM(p, op_code);
|
|
p_buf->offset = L2CAP_MIN_OFFSET;
|
|
- p_buf->len = 1;
|
|
|
|
if (op_code == GATT_RSP_READ_BY_TYPE) {
|
|
- p_pair_len = p;
|
|
+ p_pair_len = p++;
|
|
pair_len = len + 2;
|
|
- UINT8_TO_STREAM(p, pair_len);
|
|
- p_buf->len += 1;
|
|
+ size_now += 1;
|
|
+ CHECK_SIZE();
|
|
+ // this field will be backfilled in the end of this function
|
|
}
|
|
+
|
|
if (op_code != GATT_RSP_READ_BLOB && op_code != GATT_RSP_READ) {
|
|
+ size_now += 2;
|
|
+ CHECK_SIZE();
|
|
UINT16_TO_STREAM(p, handle);
|
|
- p_buf->len += 2;
|
|
}
|
|
|
|
if (op_code == GATT_REQ_PREPARE_WRITE || op_code == GATT_RSP_PREPARE_WRITE) {
|
|
+ size_now += 2;
|
|
+ CHECK_SIZE();
|
|
UINT16_TO_STREAM(p, offset);
|
|
- p_buf->len += 2;
|
|
}
|
|
|
|
if (len > 0 && p_data != NULL) {
|
|
/* ensure data not exceed MTU size */
|
|
- if (payload_size - p_buf->len < len) {
|
|
- len = payload_size - p_buf->len;
|
|
+ if (payload_size - size_now < len) {
|
|
+ len = payload_size - size_now;
|
|
/* update handle value pair length */
|
|
- if (op_code == GATT_RSP_READ_BY_TYPE) *p_pair_len = (len + 2);
|
|
+ if (op_code == GATT_RSP_READ_BY_TYPE) {
|
|
+ pair_len = (len + 2);
|
|
+ }
|
|
|
|
LOG(WARNING) << StringPrintf(
|
|
"attribute value too long, to be truncated to %d", len);
|
|
}
|
|
|
|
+ size_now += len;
|
|
+ CHECK_SIZE();
|
|
ARRAY_TO_STREAM(p, p_data, len);
|
|
- p_buf->len += len;
|
|
}
|
|
|
|
+ // backfill pair len field
|
|
+ if (op_code == GATT_RSP_READ_BY_TYPE) {
|
|
+ if (pair_len > UINT8_MAX) {
|
|
+ LOG(ERROR) << StringPrintf("pair_len greater than %d", UINT8_MAX);
|
|
+ osi_free(p_buf);
|
|
+ return nullptr;
|
|
+ }
|
|
+
|
|
+ *p_pair_len = (uint8_t)pair_len;
|
|
+ }
|
|
+
|
|
+#undef CHECK_SIZE
|
|
+
|
|
+ p_buf->len = (uint16_t)size_now;
|
|
return p_buf;
|
|
}
|
|
|