linux-toradex.git/net/socket.c, branch v3.10.61

net: socket: error on a negative msg_namelen

2014-04-14T13:42:16+00:00

[ Upstream commit dbb490b96584d4e958533fb637f08b557f505657 ]

When copying in a struct msghdr from the user, if the user has set the
msg_namelen parameter to a negative value it gets clamped to a valid
size due to a comparison between signed and unsigned values.

Ensure the syscall errors when the user passes in a negative value.

Signed-off-by: Matthew Leach 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: clamp ->msg_namelen instead of returning an error

2013-12-08T15:29:25+00:00

[ Upstream commit db31c55a6fb245fdbb752a2ca4aefec89afabb06 ]

If kmsg->msg_namelen > sizeof(struct sockaddr_storage) then in the
original code that would lead to memory corruption in the kernel if you
had audit configured.  If you didn't have audit configured it was
harmless.

There are some programs such as beta versions of Ruby which use too
large of a buffer and returning an error code breaks them.  We should
clamp the ->msg_namelen value instead.

Fixes: 1661bf364ae9 ("net: heap overflow in __audit_sockaddr()")
Reported-by: Eric Wong 
Signed-off-by: Dan Carpenter 
Tested-by: Eric Wong 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: add BUG_ON if kernel advertises msg_namelen > sizeof(struct sockaddr_storage)

2013-12-08T15:29:25+00:00

[ Upstream commit 68c6beb373955da0886d8f4f5995b3922ceda4be ]

In that case it is probable that kernel code overwrote part of the
stack. So we should bail out loudly here.

The BUG_ON may be removed in future if we are sure all protocols are
conformant.

Suggested-by: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: rework recvmsg handler msg_name and msg_namelen logic

2013-12-08T15:29:25+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: Greg Kroah-Hartman

net: heap overflow in __audit_sockaddr()

2013-11-04T12:31:00+00:00

[ Upstream commit 1661bf364ae9c506bc8795fef70d1532931be1e8 ]

We need to cap ->msg_namelen or it leads to a buffer overflow when we
to the memcpy() in __audit_sockaddr().  It requires CAP_AUDIT_CONTROL to
exploit this bug.

The call tree is:
___sys_recvmsg()
  move_addr_to_user()
    audit_sockaddr()
      __audit_sockaddr()

Reported-by: Jüri Aedla 
Signed-off-by: Dan Carpenter 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Unbreak compat_sys_{send,recv}msg

2013-06-06T18:52:14+00:00

I broke them in this commit:

    commit 1be374a0518a288147c6a7398792583200a67261
    Author: Andy Lutomirski 
    Date:   Wed May 22 14:07:44 2013 -0700

        net: Block MSG_CMSG_COMPAT in send(m)msg and recv(m)msg

This patch adds __sys_sendmsg and __sys_sendmsg as common helpers that accept
MSG_CMSG_COMPAT and blocks MSG_CMSG_COMPAT at the syscall entrypoints.  It
also reverts some unnecessary checks in sys_socketcall.

Apparently I was suffering from underscore blindness the first time around.

Signed-off-by: Andy Lutomirski 
Tested-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: Block MSG_CMSG_COMPAT in send(m)msg and recv(m)msg

2013-05-29T06:55:41+00:00

To: linux-kernel@vger.kernel.org
Cc: x86@kernel.org, trinity@vger.kernel.org, Andy Lutomirski , netdev@vger.kernel.org, "David S.
	Miller" 
Subject: [PATCH 5/5] net: Block MSG_CMSG_COMPAT in send(m)msg and recv(m)msg

MSG_CMSG_COMPAT is (AFAIK) not intended to be part of the API --
it's a hack that steals a bit to indicate to other networking code
that a compat entry was used.  So don't allow it from a non-compat
syscall.

This prevents an oops when running this code:

int main()
{
	int s;
	struct sockaddr_in addr;
	struct msghdr *hdr;

	char *highpage = mmap((void*)(TASK_SIZE_MAX - 4096), 4096,
	                      PROT_READ | PROT_WRITE,
	                      MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
	if (highpage == MAP_FAILED)
		err(1, "mmap");

	s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
	if (s == -1)
		err(1, "socket");

        addr.sin_family = AF_INET;
        addr.sin_port = htons(1);
        addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
	if (connect(s, (struct sockaddr*)&addr, sizeof(addr)) != 0)
		err(1, "connect");

	void *evil = highpage + 4096 - COMPAT_MSGHDR_SIZE;
	printf("Evil address is %p\n", evil);

	if (syscall(__NR_sendmmsg, s, evil, 1, MSG_CMSG_COMPAT) < 0)
		err(1, "sendmmsg");

	return 0;
}

Cc: David S. Miller 
Signed-off-by: Andy Lutomirski 
Signed-off-by: David S. Miller

Merge git://git.infradead.org/users/eparis/audit

2013-05-11T21:29:11+00:00

Pull audit changes from Eric Paris:
 "Al used to send pull requests every couple of years but he told me to
  just start pushing them to you directly.

  Our touching outside of core audit code is pretty straight forward.  A
  couple of interface changes which hit net/.  A simple argument bug
  calling audit functions in namei.c and the removal of some assembly
  branch prediction code on ppc"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: fix message spacing printing auid
  Revert "audit: move kaudit thread start from auditd registration to kaudit init"
  audit: vfs: fix audit_inode call in O_CREAT case of do_last
  audit: Make testing for a valid loginuid explicit.
  audit: fix event coverage of AUDIT_ANOM_LINK
  audit: use spin_lock in audit_receive_msg to process tty logging
  audit: do not needlessly take a lock in tty_audit_exit
  audit: do not needlessly take a spinlock in copy_signal
  audit: add an option to control logging of passwords with pam_tty_audit
  audit: use spin_lock_irqsave/restore in audit tty code
  helper for some session id stuff
  audit: use a consistent audit helper to log lsm information
  audit: push loginuid and sessionid processing down
  audit: stop pushing loginid, uid, sessionid as arguments
  audit: remove the old depricated kernel interface
  audit: make validity checking generic
  audit: allow checking the type of audit message in the user filter
  audit: fix build break when AUDIT_DEBUG == 2
  audit: remove duplicate export of audit_enabled
  Audit: do not print error when LSMs disabled
  ...

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2013-05-02T00:51:54+00:00

Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...

sock_close() couldn't have been called with NULL inode since at least 2.1.early

2013-04-29T19:41:43+00:00

... if not since 0.99 or so.

Signed-off-by: Al Viro