commit 32333edb82fb2009980eefc5518100068147ab82 upstream.

The commits 08c30aca9e698faddebd34f81e1196295f9dc063 "Bluetooth: Remove
RFCOMM session refcnt" and 8ff52f7d04d9cc31f1e81dcf9a2ba6335ed34905
"Bluetooth: Return RFCOMM session ptrs to avoid freed session"
allow rfcomm_recv_ua and rfcomm_session_close to delete the session
(and free the corresponding socket) and propagate NULL session pointer
to the upper callers.

Additional fix is required to terminate the loop in rfcomm_process_rx
function to avoid use of freed 'sk' memory.

The issue is only reproducible with kernel option CONFIG_PAGE_POISONING
enabled making freed memory being changed and filled up with fixed char
value used to unmask use-after-free issues.

Signed-off-by: Vignesh Raman <Vignesh_Raman@mentor.com>
Signed-off-by: Vitaly Kuzmichev <Vitaly_Kuzmichev@mentor.com>
Acked-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 093facf3634da1b0c2cc7ed106f1983da901bbab upstream.

If the current process is exiting, lingering on socket close will make
it unkillable, so we should avoid it.

Reproducer:

  #include <sys/types.h>
  #include <sys/socket.h>

  #define BTPROTO_L2CAP   0
  #define BTPROTO_SCO     2
  #define BTPROTO_RFCOMM  3

  int main()
  {
          int fd;
          struct linger ling;

          fd = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
          //or: fd = socket(PF_BLUETOOTH, SOCK_DGRAM, BTPROTO_L2CAP);
          //or: fd = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_SCO);

          ling.l_onoff = 1;
          ling.l_linger = 1000000000;
          setsockopt(fd, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling));

          return 0;
  }

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ 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 <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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
  ...

Conflicts:
	drivers/net/wireless/rt2x00/rt2x00pci.c
	net/mac80211/sta_info.c
	net/wireless/core.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

If RFCOMM_DEFER_SETUP is set in the flags, rfcomm_sock_recvmsg() returns
early with 0 without updating the possibly set msg_namelen member. This,
in turn, leads to a 128 byte kernel stack leak in net/socket.c.

Fix this by updating msg_namelen in this case. For all other cases it
will be handled in bt_sock_stream_recvmsg().

Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix to return a negative error code from the error handling
case instead of 0, as returned elsewhere in this function.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

rfcomm_session_close() sets the RFCOMM session state to BT_CLOSED.
However, in multiple places immediately before the function is
called, the RFCOMM session is set to BT_CLOSED. Therefore,
remove these unnecessary state settings.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

In rfcomm_session_del() remove the redundant call to
rfcomm_send_disc() because it is not possible for the
session to be in BT_CONNECTED state during deletion
of the session.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>