[ipxe-devel] [PATCH] Format HTTP Range with unsigned long long

[Linus Lüssing]

With an ISO 3076767744 bytes large, the menu loads fine.
However booting the live image itself fails.

Looking at the HTTP exchange with Wireshark, it was noticed
that the HTTP Get Requests upon trying to boot the live
image option in its menu makes ipxe create a broken "Range:"
header. It looks like:

"Range: -x--y"

Which the nginx obviously responds to with a "HTTP/1.1 416
Requested Range Not Satisfiable".

The "%zd" in http_format_range() is causing an integer overflow,
causing these negative numbers. %zd -> 2*31 = 2GB max.

Replaced the "%zd" with "%llu"
---
 src/net/tcp/httpcore.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/net/tcp/httpcore.c b/src/net/tcp/httpcore.c
index 4a1300c..707ca59 100644
--- a/src/net/tcp/httpcore.c
+++ b/src/net/tcp/httpcore.c
@@ -917,7 +917,7 @@ static int http_format_range ( struct http_transaction *http,
 
 	/* Construct range, if applicable */
 	if ( http->request.range.len ) {
-		return snprintf ( buf, len, "bytes=%zd-%zd",
+		return snprintf ( buf, len, "bytes=%llu-%llu",
 				  http->request.range.start,
 				  ( http->request.range.start +
 				    http->request.range.len - 1 ) );
-- 
2.0.0