1. 09 May, 2017 9 commits
  2. 03 May, 2017 4 commits
  3. 28 Apr, 2017 18 commits
  4. 27 Apr, 2017 2 commits
  5. 26 Apr, 2017 7 commits
    • James Hogan's avatar
      metag/usercopy: Add missing fixups · b2a7dcb4
      James Hogan authored
      commit b884a190 upstream.
      
      The rapf copy loops in the Meta usercopy code is missing some extable
      entries for HTP cores with unaligned access checking enabled, where
      faults occur on the instruction immediately after the faulting access.
      
      Add the fixup labels and extable entries for these cases so that corner
      case user copy failures don't cause kernel crashes.
      
      Fixes: 373cd784 ("metag: Memory handling")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      b2a7dcb4
    • James Hogan's avatar
      metag/usercopy: Fix src fixup in from user rapf loops · df7e41c9
      James Hogan authored
      commit 2c0b1df8 upstream.
      
      The fixup code to rewind the source pointer in
      __asm_copy_from_user_{32,64}bit_rapf_loop() always rewound the source by
      a single unit (4 or 8 bytes), however this is insufficient if the fault
      didn't occur on the first load in the loop, as the source pointer will
      have been incremented but nothing will have been stored until all 4
      register [pairs] are loaded.
      
      Read the LSM_STEP field of TXSTATUS (which is already loaded into a
      register), a bit like the copy_to_user versions, to determine how many
      iterations of MGET[DL] have taken place, all of which need rewinding.
      
      Fixes: 373cd784 ("metag: Memory handling")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      df7e41c9
    • James Hogan's avatar
      metag/usercopy: Set flags before ADDZ · 70b91d41
      James Hogan authored
      commit fd40eee1 upstream.
      
      The fixup code for the copy_to_user rapf loops reads TXStatus.LSM_STEP
      to decide how far to rewind the source pointer. There is a special case
      for the last execution of an MGETL/MGETD, since it leaves LSM_STEP=0
      even though the number of MGETLs/MGETDs attempted was 4. This uses ADDZ
      which is conditional upon the Z condition flag, but the AND instruction
      which masked the TXStatus.LSM_STEP field didn't set the condition flags
      based on the result.
      
      Fix that now by using ANDS which does set the flags, and also marking
      the condition codes as clobbered by the inline assembly.
      
      Fixes: 373cd784 ("metag: Memory handling")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      70b91d41
    • James Hogan's avatar
      metag/usercopy: Zero rest of buffer from copy_from_user · 1770a86a
      James Hogan authored
      commit 563ddc10 upstream.
      
      Currently we try to zero the destination for a failed read from userland
      in fixup code in the usercopy.c macros. The rest of the destination
      buffer is then zeroed from __copy_user_zeroing(), which is used for both
      copy_from_user() and __copy_from_user().
      
      Unfortunately we fail to zero in the fixup code as D1Ar1 is set to 0
      before the fixup code entry labels, and __copy_from_user() shouldn't even
      be zeroing the rest of the buffer.
      
      Move the zeroing out into copy_from_user() and rename
      __copy_user_zeroing() to raw_copy_from_user() since it no longer does
      any zeroing. This also conveniently matches the name needed for
      RAW_COPY_USER support in a later patch.
      
      Fixes: 373cd784 ("metag: Memory handling")
      Reported-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      1770a86a
    • James Hogan's avatar
      metag/usercopy: Add early abort to copy_to_user · 16bcddbe
      James Hogan authored
      commit fb8ea062 upstream.
      
      When copying to userland on Meta, if any faults are encountered
      immediately abort the copy instead of continuing on and repeatedly
      faulting, and worse potentially copying further bytes successfully to
      subsequent valid pages.
      
      Fixes: 373cd784 ("metag: Memory handling")
      Reported-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      16bcddbe
    • James Hogan's avatar
      metag/usercopy: Fix alignment error checking · e7ef4a6c
      James Hogan authored
      commit 22572119 upstream.
      
      Fix the error checking of the alignment adjustment code in
      raw_copy_from_user(), which mistakenly considers it safe to skip the
      error check when aligning the source buffer on a 2 or 4 byte boundary.
      
      If the destination buffer was unaligned it may have started to copy
      using byte or word accesses, which could well be at the start of a new
      (valid) source page. This would result in it appearing to have copied 1
      or 2 bytes at the end of the first (invalid) page rather than none at
      all.
      
      Fixes: 373cd784 ("metag: Memory handling")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      e7ef4a6c
    • James Hogan's avatar
      metag/usercopy: Drop unused macros · 1ae49ff5
      James Hogan authored
      commit ef62a2d8 upstream.
      
      Metag's lib/usercopy.c has a bunch of copy_from_user macros for larger
      copies between 5 and 16 bytes which are completely unused. Before fixing
      zeroing lets drop these macros so there is less to fix.
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: linux-metag@vger.kernel.org
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      1ae49ff5