linux-stable.git/net/llc, branch v3.2.83

net: fix infoleak in llc

2016-06-15T20:28:15+00:00

commit b8670c09f37bdf2847cc44f36511a53afc6161fd upstream.

The stack object “info” has a total size of 12 bytes. Its last byte
is padding which is not initialized and leaked via “put_cmsg”.

Signed-off-by: Kangjie Lu 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: llc: use correct size for sysctl timeout entries

2015-05-09T22:16:35+00:00

commit 6b8d9117ccb4f81b1244aafa7bc70ef8fa45fc49 upstream.

The timeout entries are sizeof(int) rather than sizeof(long), which
means that when they were getting read we'd also leak kernel memory
to userspace along with the timeout values.

Signed-off-by: Sasha Levin 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: llc: fix use after free in llc_ui_recvmsg

2014-02-15T19:20:10+00:00

[ Upstream commit 4d231b76eef6c4a6bd9c96769e191517765942cb ]

While commit 30a584d944fb fixes datagram interface in LLC, a use
after free bug has been introduced for SOCK_STREAM sockets that do
not make use of MSG_PEEK.

The flow is as follow ...

  if (!(flags & MSG_PEEK)) {
    ...
    sk_eat_skb(sk, skb, false);
    ...
  }
  ...
  if (used + offset < skb->len)
    continue;

... where sk_eat_skb() calls __kfree_skb(). Therefore, cache
original length and work on skb_len to check partial reads.

Fixes: 30a584d944fb ("[LLX]: SOCK_DGRAM interface fixes")
Signed-off-by: Daniel Borkmann 
Cc: Stephen Hemminger 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: rework recvmsg handler msg_name and msg_namelen logic

2014-01-03T04:33:33+00:00

[ Upstream commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c ]

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller 
Suggested-by: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

llc: Fix missing msg_namelen update in llc_ui_recvmsg()

2013-05-13T14:02:40+00:00

[ Upstream commit c77a4b9cffb6215a15196ec499490d116dfad181 ]

For stream sockets the code misses to update the msg_namelen member
to 0 and therefore makes net/socket.c leak the local, uninitialized
sockaddr_storage variable to userland -- 128 bytes of kernel stack
memory. The msg_namelen update is also missing for datagram sockets
in case the socket is shutting down during receive.

Fix both issues by setting msg_namelen to 0 early. It will be
updated later if we're going to fill the msg_name member.

Cc: Arnaldo Carvalho de Melo 
Signed-off-by: Mathias Krause 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

llc: fix info leak via getsockname()

2012-09-19T14:04:53+00:00

[ Upstream commit 3592aaeb80290bda0f2cf0b5456c97bfc638b192 ]

The LLC code wrongly returns 0, i.e. "success", when the socket is
zapped. Together with the uninitialized uaddrlen pointer argument from
sys_getsockname this leads to an arbitrary memory leak of up to 128
bytes kernel stack via the getsockname() syscall.

Return an error instead when the socket is zapped to prevent the info
leak. Also remove the unnecessary memset(0). We don't directly write to
the memory pointed by uaddr but memcpy() a local structure at the end of
the function that is properly initialized.

Signed-off-by: Mathias Krause 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

llc: llc_cmsg_rcv was getting called after sk_eat_skb.

2011-12-19T20:58:52+00:00

Received non stream protocol packets were calling llc_cmsg_rcv that used a
skb after that skb was released by sk_eat_skb. This caused received STP
packets to generate kernel panics.

Signed-off-by: Alexandru Juncu 
Signed-off-by: Kunjan Naik 
Signed-off-by: David S. Miller

net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

2011-10-31T23:30:30+00:00

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.

Signed-off-by: Paul Gortmaker

llc: Fix length check in llc_fixup_skb().

2011-04-12T01:59:05+00:00

Fixes bugzilla #32872

The LLC stack pretends to support non-linear skbs but there is a
direct use of skb_tail_pointer() in llc_fixup_skb().

Use pskb_may_pull() to see if data_size bytes remain and can be
accessed linearly in the packet, instead of direct pointer checks.

Signed-off-by: David S. Miller

llc: avoid skb_clone() if there is only one handler

2011-02-28T20:28:50+00:00

Signed-off-by: Changli Gao 
Signed-off-by: David S. Miller