diff options
Diffstat (limited to 'target/linux/generic/backport-5.4/080-wireguard-0091-wireguard-queueing-account-for-skb-protocol-0.patch')
| -rw-r--r-- | target/linux/generic/backport-5.4/080-wireguard-0091-wireguard-queueing-account-for-skb-protocol-0.patch | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/target/linux/generic/backport-5.4/080-wireguard-0091-wireguard-queueing-account-for-skb-protocol-0.patch b/target/linux/generic/backport-5.4/080-wireguard-0091-wireguard-queueing-account-for-skb-protocol-0.patch deleted file mode 100644 index a9ca655e74..0000000000 --- a/target/linux/generic/backport-5.4/080-wireguard-0091-wireguard-queueing-account-for-skb-protocol-0.patch +++ /dev/null @@ -1,100 +0,0 @@ -From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 -From: "Jason A. Donenfeld" <Jason@zx2c4.com> -Date: Wed, 18 Mar 2020 18:30:45 -0600 -Subject: [PATCH] wireguard: queueing: account for skb->protocol==0 - -commit a5588604af448664e796daf3c1d5a4523c60667b upstream. - -We carry out checks to the effect of: - - if (skb->protocol != wg_examine_packet_protocol(skb)) - goto err; - -By having wg_skb_examine_untrusted_ip_hdr return 0 on failure, this -means that the check above still passes in the case where skb->protocol -is zero, which is possible to hit with AF_PACKET: - - struct sockaddr_pkt saddr = { .spkt_device = "wg0" }; - unsigned char buffer[5] = { 0 }; - sendto(socket(AF_PACKET, SOCK_PACKET, /* skb->protocol = */ 0), - buffer, sizeof(buffer), 0, (const struct sockaddr *)&saddr, sizeof(saddr)); - -Additional checks mean that this isn't actually a problem in the code -base, but I could imagine it becoming a problem later if the function is -used more liberally. - -I would prefer to fix this by having wg_examine_packet_protocol return a -32-bit ~0 value on failure, which will never match any value of -skb->protocol, which would simply change the generated code from a mov -to a movzx. However, sparse complains, and adding __force casts doesn't -seem like a good idea, so instead we just add a simple helper function -to check for the zero return value. Since wg_examine_packet_protocol -itself gets inlined, this winds up not adding an additional branch to -the generated code, since the 0 return value already happens in a -mergable branch. - -Reported-by: Fabian Freyer <fabianfreyer@radicallyopensecurity.com> -Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> -Signed-off-by: David S. Miller <davem@davemloft.net> -Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> ---- - drivers/net/wireguard/device.c | 2 +- - drivers/net/wireguard/queueing.h | 8 +++++++- - drivers/net/wireguard/receive.c | 4 ++-- - 3 files changed, 10 insertions(+), 4 deletions(-) - ---- a/drivers/net/wireguard/device.c -+++ b/drivers/net/wireguard/device.c -@@ -122,7 +122,7 @@ static netdev_tx_t wg_xmit(struct sk_buf - u32 mtu; - int ret; - -- if (unlikely(wg_skb_examine_untrusted_ip_hdr(skb) != skb->protocol)) { -+ if (unlikely(!wg_check_packet_protocol(skb))) { - ret = -EPROTONOSUPPORT; - net_dbg_ratelimited("%s: Invalid IP packet\n", dev->name); - goto err; ---- a/drivers/net/wireguard/queueing.h -+++ b/drivers/net/wireguard/queueing.h -@@ -66,7 +66,7 @@ struct packet_cb { - #define PACKET_PEER(skb) (PACKET_CB(skb)->keypair->entry.peer) - - /* Returns either the correct skb->protocol value, or 0 if invalid. */ --static inline __be16 wg_skb_examine_untrusted_ip_hdr(struct sk_buff *skb) -+static inline __be16 wg_examine_packet_protocol(struct sk_buff *skb) - { - if (skb_network_header(skb) >= skb->head && - (skb_network_header(skb) + sizeof(struct iphdr)) <= -@@ -81,6 +81,12 @@ static inline __be16 wg_skb_examine_untr - return 0; - } - -+static inline bool wg_check_packet_protocol(struct sk_buff *skb) -+{ -+ __be16 real_protocol = wg_examine_packet_protocol(skb); -+ return real_protocol && skb->protocol == real_protocol; -+} -+ - static inline void wg_reset_packet(struct sk_buff *skb) - { - skb_scrub_packet(skb, true); ---- a/drivers/net/wireguard/receive.c -+++ b/drivers/net/wireguard/receive.c -@@ -56,7 +56,7 @@ static int prepare_skb_header(struct sk_ - size_t data_offset, data_len, header_len; - struct udphdr *udp; - -- if (unlikely(wg_skb_examine_untrusted_ip_hdr(skb) != skb->protocol || -+ if (unlikely(!wg_check_packet_protocol(skb) || - skb_transport_header(skb) < skb->head || - (skb_transport_header(skb) + sizeof(struct udphdr)) > - skb_tail_pointer(skb))) -@@ -388,7 +388,7 @@ static void wg_packet_consume_data_done( - */ - skb->ip_summed = CHECKSUM_UNNECESSARY; - skb->csum_level = ~0; /* All levels */ -- skb->protocol = wg_skb_examine_untrusted_ip_hdr(skb); -+ skb->protocol = wg_examine_packet_protocol(skb); - if (skb->protocol == htons(ETH_P_IP)) { - len = ntohs(ip_hdr(skb)->tot_len); - if (unlikely(len < sizeof(struct iphdr))) |