1. 27 Apr, 2016 4 commits
  2. 26 Apr, 2016 6 commits
  3. 15 Apr, 2016 23 commits
  4. 14 Apr, 2016 6 commits
    • Mike Snitzer's avatar
      dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros · 9567366f
      Mike Snitzer authored
      The READ_LOCK macro was incorrectly returning -EINVAL if
      dm_bm_is_read_only() was true -- it will always be true once the cache
      metadata transitions to read-only by dm_cache_metadata_set_read_only().
      
      Wrap READ_LOCK and WRITE_LOCK multi-statement macros in do {} while(0).
      Also, all accesses of the 'cmd' argument passed to these related macros
      are now encapsulated in parenthesis.
      
      A follow-up patch can be developed to eliminate the use of macros in
      favor of pure C code.  Avoiding that now given that this needs to apply
      to stable@.
      Reported-by: default avatarBen Hutchings <ben@decadent.org.uk>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Fixes: d14fcf3d ("dm cache: make sure every metadata function checks fail_io")
      Cc: stable@vger.kernel.org
      9567366f
    • Linus Torvalds's avatar
      /proc/iomem: only expose physical resource addresses to privileged users · 51d7b120
      Linus Torvalds authored
      In commit c4004b02 ("x86: remove the kernel code/data/bss resources
      from /proc/iomem") I was hoping to remove the phyiscal kernel address
      data from /proc/iomem entirely, but that had to be reverted because some
      system programs actually use it.
      
      This limits all the detailed resource information to properly
      credentialed users instead.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      51d7b120
    • Linus Torvalds's avatar
      pci-sysfs: use proper file capability helper function · ab0fa82b
      Linus Torvalds authored
      The PCI config access checked the file capabilities correctly, but used
      the itnernal security capability check rather than the helper function
      that is actually meant for that.
      
      The security_capable() has unusual return values and is not meant to be
      used elsewhere (the only other use is in the capability checking
      functions that we actually intend people to use, and this odd PCI usage
      really stood out when looking around the capability code.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ab0fa82b
    • Linus Torvalds's avatar
      Make file credentials available to the seqfile interfaces · 34dbbcdb
      Linus Torvalds authored
      A lot of seqfile users seem to be using things like %pK that uses the
      credentials of the current process, but that is actually completely
      wrong for filesystem interfaces.
      
      The unix semantics for permission checking files is to check permissions
      at _open_ time, not at read or write time, and that is not just a small
      detail: passing off stdin/stdout/stderr to a suid application and making
      the actual IO happen in privileged context is a classic exploit
      technique.
      
      So if we want to be able to look at permissions at read time, we need to
      use the file open credentials, not the current ones.  Normal file
      accesses can just use "f_cred" (or any of the helper functions that do
      that, like file_ns_capable()), but the seqfile interfaces do not have
      any such options.
      
      It turns out that seq_file _does_ save away the user_ns information of
      the file, though.  Since user_ns is just part of the full credential
      information, replace that special case with saving off the cred pointer
      instead, and suddenly seq_file has all the permission information it
      needs.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      34dbbcdb
    • Linus Torvalds's avatar
      Revert "x86: remove the kernel code/data/bss resources from /proc/iomem" · 4046d6e8
      Linus Torvalds authored
      This reverts commit c4004b02.
      
      Sadly, my hope that nobody would actually use the special kernel entries
      in /proc/iomem were dashed by kexec.  Which reads /proc/iomem explicitly
      to find the kernel base address.  Nasty.
      
      Anyway, that means we can't do the sane and simple thing and just remove
      the entries, and we'll instead have to mask them out based on permissions.
      Reported-by: default avatarZhengyu Zhang <zhezhang@redhat.com>
      Reported-by: default avatarDave Young <dyoung@redhat.com>
      Reported-by: default avatarFreeman Zhang <freeman.zhang1992@gmail.com>
      Reported-by: default avatarEmrah Demir <ed@abdsec.com>
      Reported-by: default avatarBaoquan He <bhe@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4046d6e8
    • Stefan Agner's avatar
      pwm: fsl-ftm: Use flat regmap cache · ad06fdee
      Stefan Agner authored
      Use flat regmap cache to avoid lockdep warning at probe:
      
      [    0.697285] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2755 lockdep_trace_alloc+0x15c/0x160()
      [    0.697449] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
      
      The RB-tree regmap cache needs to allocate new space on first writes.
      However, allocations in an atomic context (e.g. when a spinlock is held)
      are not allowed. The function regmap_write calls map->lock, which
      acquires a spinlock in the fast_io case. Since the pwm-fsl-ftm driver
      uses MMIO, the regmap bus of type regmap_mmio is being used which has
      fast_io set to true.
      
      The MMIO space of the pwm-fsl-ftm driver is reasonable condense, hence
      using the much faster flat regmap cache is anyway the better choice.
      Signed-off-by: default avatarStefan Agner <stefan@agner.ch>
      Cc: Mark Brown <broonie@kernel.org>
      Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
      ad06fdee
  5. 13 Apr, 2016 1 commit