This is a note to let you know that I've just added the patch titled
af_unix: Add sockaddr length checks before accessing sa_family in bind and connect handlers
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
af_unix-add-sockaddr-length-checks-before-accessing-sa_family-in-bind-and-connect-handlers.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Jun 29 19:38:17 CEST 2017
From: Mateusz Jurczyk <mjurczyk@xxxxxxxxxx>
Date: Thu, 8 Jun 2017 11:13:36 +0200
Subject: af_unix: Add sockaddr length checks before accessing sa_family in bind and connect handlers
From: Mateusz Jurczyk <mjurczyk@xxxxxxxxxx>
[ Upstream commit defbcf2decc903a28d8398aa477b6881e711e3ea ]
Verify that the caller-provided sockaddr structure is large enough to
contain the sa_family field, before accessing it in bind() and connect()
handlers of the AF_UNIX socket. Since neither syscall enforces a minimum
size of the corresponding memory region, very short sockaddrs (zero or
one byte long) result in operating on uninitialized memory while
referencing .sa_family.
Signed-off-by: Mateusz Jurczyk <mjurczyk@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/unix/af_unix.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -997,7 +997,8 @@ static int unix_bind(struct socket *sock
struct path path = { NULL, NULL };
err = -EINVAL;
- if (sunaddr->sun_family != AF_UNIX)
+ if (addr_len < offsetofend(struct sockaddr_un, sun_family) ||
+ sunaddr->sun_family != AF_UNIX)
goto out;
if (addr_len == sizeof(short)) {
@@ -1108,6 +1109,10 @@ static int unix_dgram_connect(struct soc
unsigned int hash;
int err;
+ err = -EINVAL;
+ if (alen < offsetofend(struct sockaddr, sa_family))
+ goto out;
+
if (addr->sa_family != AF_UNSPEC) {
err = unix_mkname(sunaddr, alen, &hash);
if (err < 0)
Patches currently in stable-queue which might be from mjurczyk@xxxxxxxxxx are
queue-4.4/decnet-dn_rtmsg-improve-input-length-sanitization-in-dnrmg_receive_user_skb.patch
queue-4.4/af_unix-add-sockaddr-length-checks-before-accessing-sa_family-in-bind-and-connect-handlers.patch