net: wget: prevent overwriting reserved memory
This introduces the valid range check to store the received
blocks using lmb. The same logic is implemented in tftp.
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/net/wget.c b/net/wget.c
index 8bb4d72..6f97eb1 100644
--- a/net/wget.c
+++ b/net/wget.c
@@ -4,16 +4,20 @@
* Copyright Duncan Hare <dh@synoia.com> 2017
*/
+#include <asm/global_data.h>
#include <command.h>
#include <common.h>
#include <display_options.h>
#include <env.h>
#include <image.h>
+#include <lmb.h>
#include <mapmem.h>
#include <net.h>
#include <net/tcp.h>
#include <net/wget.h>
+DECLARE_GLOBAL_DATA_PTR;
+
static const char bootfile1[] = "GET ";
static const char bootfile3[] = " HTTP/1.0\r\n\r\n";
static const char http_eom[] = "\r\n\r\n";
@@ -56,6 +60,29 @@
static unsigned int retry_tcp_seq_num; /* TCP retry sequence number */
static int retry_len; /* TCP retry length */
+static ulong wget_load_size;
+
+/**
+ * wget_init_max_size() - initialize maximum load size
+ *
+ * Return: 0 if success, -1 if fails
+ */
+static int wget_init_load_size(void)
+{
+ struct lmb lmb;
+ phys_size_t max_size;
+
+ lmb_init_and_reserve(&lmb, gd->bd, (void *)gd->fdt_blob);
+
+ max_size = lmb_get_free_size(&lmb, image_load_addr);
+ if (!max_size)
+ return -1;
+
+ wget_load_size = max_size;
+
+ return 0;
+}
+
/**
* store_block() - store block in memory
* @src: source of data
@@ -64,10 +91,25 @@
*/
static inline int store_block(uchar *src, unsigned int offset, unsigned int len)
{
+ ulong store_addr = image_load_addr + offset;
ulong newsize = offset + len;
uchar *ptr;
- ptr = map_sysmem(image_load_addr + offset, len);
+ if (IS_ENABLED(CONFIG_LMB)) {
+ ulong end_addr = image_load_addr + wget_load_size;
+
+ if (!end_addr)
+ end_addr = ULONG_MAX;
+
+ if (store_addr < image_load_addr ||
+ store_addr + len > end_addr) {
+ printf("\nwget error: ");
+ printf("trying to overwrite reserved memory...\n");
+ return -1;
+ }
+ }
+
+ ptr = map_sysmem(store_addr, len);
memcpy(ptr, src, len);
unmap_sysmem(ptr);
@@ -248,25 +290,39 @@
net_boot_file_size = 0;
- if (len > hlen)
- store_block(pkt + hlen, 0, len - hlen);
+ if (len > hlen) {
+ if (store_block(pkt + hlen, 0, len - hlen) != 0) {
+ wget_loop_state = NETLOOP_FAIL;
+ wget_fail("wget: store error\n", tcp_seq_num, tcp_ack_num, action);
+ net_set_state(NETLOOP_FAIL);
+ return;
+ }
+ }
debug_cond(DEBUG_WGET,
"wget: Connected Pkt %p hlen %x\n",
pkt, hlen);
for (i = 0; i < pkt_q_idx; i++) {
+ int err;
+
ptr1 = map_sysmem(
(phys_addr_t)(pkt_q[i].pkt),
pkt_q[i].len);
- store_block(ptr1,
- pkt_q[i].tcp_seq_num -
- initial_data_seq_num,
- pkt_q[i].len);
+ err = store_block(ptr1,
+ pkt_q[i].tcp_seq_num -
+ initial_data_seq_num,
+ pkt_q[i].len);
unmap_sysmem(ptr1);
debug_cond(DEBUG_WGET,
"wget: Connctd pkt Q %p len %x\n",
pkt_q[i].pkt, pkt_q[i].len);
+ if (err) {
+ wget_loop_state = NETLOOP_FAIL;
+ wget_fail("wget: store error\n", tcp_seq_num, tcp_ack_num, action);
+ net_set_state(NETLOOP_FAIL);
+ return;
+ }
}
}
}
@@ -338,6 +394,7 @@
len) != 0) {
wget_fail("wget: store error\n",
tcp_seq_num, tcp_ack_num, action);
+ net_set_state(NETLOOP_FAIL);
return;
}
@@ -428,6 +485,15 @@
debug_cond(DEBUG_WGET,
"\nwget:Load address: 0x%lx\nLoading: *\b", image_load_addr);
+ if (IS_ENABLED(CONFIG_LMB)) {
+ if (wget_init_load_size()) {
+ printf("\nwget error: ");
+ printf("trying to overwrite reserved memory...\n");
+ net_set_state(NETLOOP_FAIL);
+ return;
+ }
+ }
+
net_set_timeout_handler(wget_timeout, wget_timeout_handler);
tcp_set_tcp_handler(wget_handler);