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  1. 09 May, 2016 9 commits
  3. 02 May, 2016 2 commits
    • Ignat Korchagin's avatar
      USB: usbip: fix potential out-of-bounds write · 7679a59d
      Ignat Korchagin authored 
      commit b348d7dd upstream.

Fix potential out-of-bounds write to urb->transfer_buffer
usbip handles network communication directly in the kernel. When receiving a
packet from its peer, usbip code parses headers according to protocol. As
part of this parsing urb->actual_length is filled. Since the input for
urb->actual_length comes from the network, it should be treated as untrusted.
Any entity controlling the network may put any value in the input and the
preallocated urb->transfer_buffer may not be large enough to hold the data.
Thus, the malicious entity is able to write arbitrary data to kernel memory.
Signed-off-by: default avatarIgnat Korchagin <ignat.korchagin@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reference: CVE-2016-3955
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      7679a59d
    • Hector Marco-Gisbert's avatar
      x86/mm/32: Enable full randomization on i386 and X86_32 · 861d04db
      Hector Marco-Gisbert authored 
      commit 8b8addf8 upstream.

Currently on i386 and on X86_64 when emulating X86_32 in legacy mode, only
the stack and the executable are randomized but not other mmapped files
(libraries, vDSO, etc.). This patch enables randomization for the
libraries, vDSO and mmap requests on i386 and in X86_32 in legacy mode.

By default on i386 there are 8 bits for the randomization of the libraries,
vDSO and mmaps which only uses 1MB of VA.

This patch preserves the original randomness, using 1MB of VA out of 3GB or
4GB. We think that 1MB out of 3GB is not a big cost for having the ASLR.

The first obvious security benefit is that all objects are randomized (not
only the stack and the executable) in legacy mode which highly increases
the ASLR effectiveness, otherwise the attackers may use these
non-randomized areas. But also sensitive setuid/setgid applications are
more secure because currently, attackers can disable the randomization of
these applications by setting the ulimit stack to "unlimited". This is a
very old and widely known trick to disable the ASLR in i386 which has been
allowed for too long.

Another trick used to disable the ASLR was to set the ADDR_NO_RANDOMIZE
personality flag, but fortunately this doesn't work on setuid/setgid
applications because there is security checks which clear Security-relevant
flags.

This patch always randomizes the mmap_legacy_base address, removing the
possibility to disable the ASLR by setting the stack to "unlimited".
Signed-off-by: default avatarHector Marco-Gisbert <hecmargi@upv.es>
Acked-by: default avatarIsmael Ripoll Ripoll <iripoll@upv.es>
Acked-by: default avatarKees Cook <keescook@chromium.org>
Acked-by: default avatarArjan van de Ven <arjan@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1457639460-5242-1-git-send-email-hecmargi@upv.esSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reference: CVE-2016-3672
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      861d04db
  5. 29 Apr, 2016 1 commit
  7. 26 Apr, 2016 28 commits
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