summaryrefslogtreecommitdiff
path: root/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-48687.patch
diff options
context:
space:
mode:
Diffstat (limited to 'meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-48687.patch')
-rw-r--r--meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-48687.patch76
1 files changed, 76 insertions, 0 deletions
diff --git a/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-48687.patch b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-48687.patch
new file mode 100644
index 000000000..53b751d83
--- /dev/null
+++ b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-48687.patch
@@ -0,0 +1,76 @@
+From 076f2479fc5a15c4a970ca3b5e57d42ba09a31fa Mon Sep 17 00:00:00 2001
+From: David Lebrun <dlebrun@google.com>
+Date: Fri, 2 Sep 2022 10:45:06 +0100
+Subject: ipv6: sr: fix out-of-bounds read when setting HMAC data.
+
+[ Upstream commit 84a53580c5d2138c7361c7c3eea5b31827e63b35 ]
+
+The SRv6 layer allows defining HMAC data that can later be used to sign IPv6
+Segment Routing Headers. This configuration is realised via netlink through
+four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and
+SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual
+length of the SECRET attribute, it is possible to provide invalid combinations
+(e.g., secret = "", secretlen = 64). This case is not checked in the code and
+with an appropriately crafted netlink message, an out-of-bounds read of up
+to 64 bytes (max secret length) can occur past the skb end pointer and into
+skb_shared_info:
+
+Breakpoint 1, seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208
+208 memcpy(hinfo->secret, secret, slen);
+(gdb) bt
+ #0 seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208
+ #1 0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,
+ extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 <init_net>, family=<optimized out>,
+ family=<optimized out>) at net/netlink/genetlink.c:731
+ #2 0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,
+ family=0xffffffff82fef6c0 <seg6_genl_family>) at net/netlink/genetlink.c:775
+ #3 genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792
+ #4 0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 <genl_rcv_msg>)
+ at net/netlink/af_netlink.c:2501
+ #5 0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803
+ #6 0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)
+ at net/netlink/af_netlink.c:1319
+ #7 netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=<optimized out>)
+ at net/netlink/af_netlink.c:1345
+ #8 0xffffffff81dff9a4 in netlink_sendmsg (sock=<optimized out>, msg=0xffffc90000ba7e48, len=<optimized out>) at net/netlink/af_netlink.c:1921
+...
+(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)->head + ((struct sk_buff *)0xffff88800b1f9f00)->end
+$1 = 0xffff88800b1b76c0
+(gdb) p/x secret
+$2 = 0xffff88800b1b76c0
+(gdb) p slen
+$3 = 64 '@'
+
+The OOB data can then be read back from userspace by dumping HMAC state. This
+commit fixes this by ensuring SECRETLEN cannot exceed the actual length of
+SECRET.
+
+Reported-by: Lucas Leong <wmliang.tw@gmail.com>
+Tested: verified that EINVAL is correctly returned when secretlen > len(secret)
+Fixes: 4f4853dc1c9c1 ("ipv6: sr: implement API to control SR HMAC structure")
+Signed-off-by: David Lebrun <dlebrun@google.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+---
+ net/ipv6/seg6.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
+index d2f8138e5a73a5..2278c0234c4979 100644
+--- a/net/ipv6/seg6.c
++++ b/net/ipv6/seg6.c
+@@ -135,6 +135,11 @@ static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
+ goto out_unlock;
+ }
+
++ if (slen > nla_len(info->attrs[SEG6_ATTR_SECRET])) {
++ err = -EINVAL;
++ goto out_unlock;
++ }
++
+ if (hinfo) {
+ err = seg6_hmac_info_del(net, hmackeyid);
+ if (err)
+--
+cgit 1.2.3-korg
+