msm: camera: Add proper camera close sequence

Update camera driver to handle closing sequence properly
when there is a crash in userspace threads to restart
camera again.

Change-Id: Ic1956975fd18d262e9cf503055fb09d391f8c7d7
CRs-Fixed: 443096
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>
signal: always clear sa_restorer on execve

When the new signal handlers are set up, the location of sa_restorer is
not cleared, leaking a parent process's address space location to
children.  This allows for a potential bypass of the parent's ASLR by
examining the sa_restorer value returned when calling sigaction().

Based on what should be considered "secret" about addresses, it only
matters across the exec not the fork (since the VMAs haven't changed
until the exec).  But since exec sets SIG_DFL and keeps sa_restorer,
this is where it should be fixed.

Given the few uses of sa_restorer, a "set" function was not written
since this would be the only use.  Instead, we use
__ARCH_HAS_SA_RESTORER, as already done in other places.

Example of the leak before applying this patch:

  $ cat /proc/$$/maps
  ...
  7fb9f3083000-7fb9f3238000 r-xp 00000000 fd:01 404469 .../libc-2.15.so
  ...
  $ ./leak
  ...
  7f278bc74000-7f278be29000 r-xp 00000000 fd:01 404469 .../libc-2.15.so
  ...
  1 0 (nil) 0x7fb9f30b94a0
  2 4000000 (nil) 0x7f278bcaa4a0
  3 4000000 (nil) 0x7f278bcaa4a0
  4 0 (nil) 0x7fb9f30b94a0
  ...

[akpm@linux-foundation.org: use SA_RESTORER for backportability]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Emese Revfy <re.emese@gmail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Julien Tinnes <jln@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Change-Id: I7ae396ee90c2339c86f7b773d15f5571f8fd54c5
Signed-off-by: Goberu Gopal <ggober@codeaurora.org>
Revert "Revert "msm_fb: display: wait4vsync before set suspend flag""

This reverts commit a3c473855ea59706c6fb21eacdc1e68d7f1960b2

Change-Id: Iaef868cb41ad50ab3324aa34be7e2ee35ea01497
Signed-off-by: Mayank Goyal <goyalm@codeaurora.org>
Merge "signal: always clear sa_restorer on execve"
Merge "Revert "Revert "msm_fb: display: wait4vsync before set suspend flag"""
Merge "msm: camera: Add proper camera close sequence"