1. 06 Jan, 2019 1 commit
    • Masahiro Yamada's avatar
      jump_label: move 'asm goto' support test to Kconfig · e9666d10
      Masahiro Yamada authored
      Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".
      
      The jump label is controlled by HAVE_JUMP_LABEL, which is defined
      like this:
      
        #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
        # define HAVE_JUMP_LABEL
        #endif
      
      We can improve this by testing 'asm goto' support in Kconfig, then
      make JUMP_LABEL depend on CC_HAS_ASM_GOTO.
      
      Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
      match to the real kernel capability.
      Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Tested-by: default avatarSedat Dilek <sedat.dilek@gmail.com>
      e9666d10
  2. 04 Jan, 2019 1 commit
    • Linus Torvalds's avatar
      Remove 'type' argument from access_ok() function · 96d4f267
      Linus Torvalds authored
      Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
      of the user address range verification function since we got rid of the
      old racy i386-only code to walk page tables by hand.
      
      It existed because the original 80386 would not honor the write protect
      bit when in kernel mode, so you had to do COW by hand before doing any
      user access.  But we haven't supported that in a long time, and these
      days the 'type' argument is a purely historical artifact.
      
      A discussion about extending 'user_access_begin()' to do the range
      checking resulted this patch, because there is no way we're going to
      move the old VERIFY_xyz interface to that model.  And it's best done at
      the end of the merge window when I've done most of my merges, so let's
      just get this done once and for all.
      
      This patch was mostly done with a sed-script, with manual fix-ups for
      the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
      
      There were a couple of notable cases:
      
       - csky still had the old "verify_area()" name as an alias.
      
       - the iter_iov code had magical hardcoded knowledge of the actual
         values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
         really used it)
      
       - microblaze used the type argument for a debug printout
      
      but other than those oddities this should be a total no-op patch.
      
      I tried to fix up all architectures, did fairly extensive grepping for
      access_ok() uses, and the changes are trivial, but I may have missed
      something.  Any missed conversion should be trivially fixable, though.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      96d4f267
  3. 03 Jan, 2019 2 commits
  4. 02 Jan, 2019 32 commits
  5. 01 Jan, 2019 3 commits
    • Willem de Bruijn's avatar
      ip: validate header length on virtual device xmit · cb9f1b78
      Willem de Bruijn authored
      KMSAN detected read beyond end of buffer in vti and sit devices when
      passing truncated packets with PF_PACKET. The issue affects additional
      ip tunnel devices.
      
      Extend commit 76c0ddd8 ("ip6_tunnel: be careful when accessing the
      inner header") and commit ccfec9e5 ("ip_tunnel: be careful when
      accessing the inner header").
      
      Move the check to a separate helper and call at the start of each
      ndo_start_xmit function in net/ipv4 and net/ipv6.
      
      Minor changes:
      - convert dev_kfree_skb to kfree_skb on error path,
        as dev_kfree_skb calls consume_skb which is not for error paths.
      - use pskb_network_may_pull even though that is pedantic here,
        as the same as pskb_may_pull for devices without llheaders.
      - do not cache ipv6 hdrs if used only once
        (unsafe across pskb_may_pull, was more relevant to earlier patch)
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      cb9f1b78
    • Zhu Yanjun's avatar
      net: rds: remove unnecessary NULL check · 4087d2bc
      Zhu Yanjun authored
      In kfree, the NULL check is done.
      Signed-off-by: default avatarZhu Yanjun <yanjun.zhu@oracle.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4087d2bc
    • Deepa Dinamani's avatar
      sock: Make sock->sk_stamp thread-safe · 3a0ed3e9
      Deepa Dinamani authored
      Al Viro mentioned (Message-ID
      <20170626041334.GZ10672@ZenIV.linux.org.uk>)
      that there is probably a race condition
      lurking in accesses of sk_stamp on 32-bit machines.
      
      sock->sk_stamp is of type ktime_t which is always an s64.
      On a 32 bit architecture, we might run into situations of
      unsafe access as the access to the field becomes non atomic.
      
      Use seqlocks for synchronization.
      This allows us to avoid using spinlocks for readers as
      readers do not need mutual exclusion.
      
      Another approach to solve this is to require sk_lock for all
      modifications of the timestamps. The current approach allows
      for timestamps to have their own lock: sk_stamp_lock.
      This allows for the patch to not compete with already
      existing critical sections, and side effects are limited
      to the paths in the patch.
      
      The addition of the new field maintains the data locality
      optimizations from
      commit 9115e8cd ("net: reorganize struct sock for better data
      locality")
      
      Note that all the instances of the sk_stamp accesses
      are either through the ioctl or the syscall recvmsg.
      Signed-off-by: default avatarDeepa Dinamani <deepa.kernel@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3a0ed3e9
  6. 31 Dec, 2018 1 commit
    • Cong Wang's avatar
      netrom: fix locking in nr_find_socket() · 7314f548
      Cong Wang authored
      nr_find_socket(), nr_find_peer() and nr_find_listener() lock the
      sock after finding it in the global list. However, the call path
      requires BH disabled for the sock lock consistently.
      
      Actually the locking is unnecessary at this point, we can just hold
      the sock refcnt to make sure it is not gone after we unlock the global
      list, and lock it later only when needed.
      
      Reported-and-tested-by: syzbot+f621cda8b7e598908efa@syzkaller.appspotmail.com
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7314f548