diff options
Diffstat (limited to 'package/utils/busybox/patches/205-udhcpc_allow_zero_length_options.patch')
| -rw-r--r-- | package/utils/busybox/patches/205-udhcpc_allow_zero_length_options.patch | 49 |
1 files changed, 0 insertions, 49 deletions
diff --git a/package/utils/busybox/patches/205-udhcpc_allow_zero_length_options.patch b/package/utils/busybox/patches/205-udhcpc_allow_zero_length_options.patch deleted file mode 100644 index abe8baf54f..0000000000 --- a/package/utils/busybox/patches/205-udhcpc_allow_zero_length_options.patch +++ /dev/null @@ -1,49 +0,0 @@ -From 7eed119b84b0f7efb7ef351940dd895dc2379eb3 Mon Sep 17 00:00:00 2001 -From: Russell Senior <russell@personaltelco.net> -Date: Mon, 15 Mar 2021 23:27:58 -0700 -Subject: [PATCH v2] udhcpc: ignore zero-length DHCP options - -Discovered that the DHCP server on a TrendNet router (unknown model) -provides a zero-length option 12 (Host Name) in the DHCP ACK message. This -has the effect of causing udhcpc to drop the rest of the options, including -option 51 (IP Address Lease Time), 3 (Router), and 6 (Domain Name Server), -most importantly leaving the OpenWrt device with no default gateway. - -The TrendNet behavior violates RFC 2132, which in Section 3.14 declares that -option 12 has a miniumum length of 1 octet. It is perhaps not a cosmic coincidence -that I found this behavior on Pi Day. - -This patch allows zero length options without bailing out, by simply skipping them. - -v2 changelog: -* advance the optionptr by two bytes, not one; -* add a message to warn about the rfc violation; - -Signed-off-by: Russell Senior <russell@personaltelco.net> ---- - networking/udhcp/common.c | 9 +++++++-- - 1 file changed, 7 insertions(+), 2 deletions(-) - -diff --git a/networking/udhcp/common.c b/networking/udhcp/common.c -index 4bc719001..a16fd85d0 100644 ---- a/networking/udhcp/common.c -+++ b/networking/udhcp/common.c -@@ -277,8 +277,13 @@ uint8_t* FAST_FUNC udhcp_scan_options(struct dhcp_packet *packet, struct dhcp_sc - goto complain; /* complain and return NULL */ - len = 2 + scan_state->optionptr[OPT_LEN]; - scan_state->rem -= len; -- /* So far no valid option with length 0 known. */ -- if (scan_state->rem < 0 || scan_state->optionptr[OPT_LEN] == 0) -+ /* skip any options with zero length */ -+ if (scan_state->optionptr[OPT_LEN] == 0) { -+ scan_state->optionptr += 2; -+ bb_simple_error_msg("warning: zero length DHCP option violates rfc2132, skipping"); -+ continue; -+ } -+ if (scan_state->rem < 0) - goto complain; /* complain and return NULL */ - - if (scan_state->optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) { --- -2.30.1 - |