1. 14 3月, 2019 34 次提交
  2. 10 3月, 2019 4 次提交
  3. 06 3月, 2019 2 次提交
    • A
      x86/uaccess: Don't leak the AC flag into __put_user() value evaluation · 7371994d
      Andy Lutomirski 提交于
      commit 2a418cf3f5f1caf911af288e978d61c9844b0695 upstream.
      
      When calling __put_user(foo(), ptr), the __put_user() macro would call
      foo() in between __uaccess_begin() and __uaccess_end().  If that code
      were buggy, then those bugs would be run without SMAP protection.
      
      Fortunately, there seem to be few instances of the problem in the
      kernel. Nevertheless, __put_user() should be fixed to avoid doing this.
      Therefore, evaluate __put_user()'s argument before setting AC.
      
      This issue was noticed when an objtool hack by Peter Zijlstra complained
      about genregs_get() and I compared the assembly output to the C source.
      
       [ bp: Massage commit message and fixed up whitespace. ]
      
      Fixes: 11f1a4b9 ("x86: reorganize SMAP handling in user space accesses")
      Signed-off-by: NAndy Lutomirski <luto@kernel.org>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: stable@vger.kernel.org
      Link: http://lkml.kernel.org/r/20190225125231.845656645@infradead.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7371994d
    • P
      MIPS: eBPF: Fix icache flush end address · 9f77e4cb
      Paul Burton 提交于
      commit d1a2930d8a992fb6ac2529449f81a0056e1b98d1 upstream.
      
      The MIPS eBPF JIT calls flush_icache_range() in order to ensure the
      icache observes the code that we just wrote. Unfortunately it gets the
      end address calculation wrong due to some bad pointer arithmetic.
      
      The struct jit_ctx target field is of type pointer to u32, and as such
      adding one to it will increment the address being pointed to by 4 bytes.
      Therefore in order to find the address of the end of the code we simply
      need to add the number of 4 byte instructions emitted, but we mistakenly
      add the number of instructions multiplied by 4. This results in the call
      to flush_icache_range() operating on a memory region 4x larger than
      intended, which is always wasteful and can cause crashes if we overrun
      into an unmapped page.
      
      Fix this by correcting the pointer arithmetic to remove the bogus
      multiplication, and use braces to remove the need for a set of brackets
      whilst also making it obvious that the target field is a pointer.
      Signed-off-by: NPaul Burton <paul.burton@mips.com>
      Fixes: b6bd53f9 ("MIPS: Add missing file for eBPF JIT.")
      Cc: Alexei Starovoitov <ast@kernel.org>
      Cc: Daniel Borkmann <daniel@iogearbox.net>
      Cc: Martin KaFai Lau <kafai@fb.com>
      Cc: Song Liu <songliubraving@fb.com>
      Cc: Yonghong Song <yhs@fb.com>
      Cc: netdev@vger.kernel.org
      Cc: bpf@vger.kernel.org
      Cc: linux-mips@vger.kernel.org
      Cc: stable@vger.kernel.org # v4.13+
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      9f77e4cb