[PATCH 2/2] wget: rework the logic to validate the load address

[Sughosh Ganu]

Use the lmb_read_check() function to verify if it is safe to use a
region of memory to load data from the wget command. The current logic
checks the amount of free memory available, starting from the 'load
address'. This call fails if the same region of memory has been used
earlier. This used to work earlier as the LMB memory map had a local
scope and was not persistent. Fix this issue by using the
lmb_read_check() call instead which only returns an error in case the
memory region has been marked for not allowing re-use.

Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
---

Note: To be applied on next, on top of
https://patchwork.ozlabs.org/project/uboot/patch/20240913073251.2286529-2-prasad.kummari@amd.com/

 net/wget.c | 36 +-----------------------------------
 1 file changed, 1 insertion(+), 35 deletions(-)

diff --git a/net/wget.c b/net/wget.c
index 4a168641c6..a88c31f236 100644
--- a/net/wget.c
+++ b/net/wget.c
@@ -64,26 +64,6 @@ static unsigned int retry_tcp_ack_num;	/* TCP retry acknowledge number*/
 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)
-{
-	phys_size_t max_size;
-
-	max_size = lmb_get_free_size(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
@@ -97,13 +77,8 @@ static inline int store_block(uchar *src, unsigned int offset, unsigned int len)
 	uchar *ptr;
 
 	if (CONFIG_IS_ENABLED(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) {
+		    lmb_read_check(store_addr, len)) {
 			printf("\nwget error: ");
 			printf("trying to overwrite reserved memory...\n");
 			return -1;
@@ -493,15 +468,6 @@ void wget_start(void)
 	debug_cond(DEBUG_WGET,
 		   "\nwget:Load address: 0x%lx\nLoading: *\b", image_load_addr);
 
-	if (CONFIG_IS_ENABLED(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);
 
-- 
2.34.1