bpf, mips: fix off-by-one in ctx offset allocation
commitb4e76f7e6d3200462c6354a6ad4ae167459e61f8
authorDaniel Borkmann <daniel@iogearbox.net>
Thu, 14 Jul 2016 11:57:55 +0000 (14 13:57 +0200)
committerRalf Baechle <ralf@linux-mips.org>
Thu, 21 Jul 2016 09:12:34 +0000 (21 11:12 +0200)
tree701e7e28615f7c9551186ff677dca6cba4a9b104
parent58a7e1c140f3ad61646bc0cd9a1f6a9cafc0b225
bpf, mips: fix off-by-one in ctx offset allocation

Dan Carpenter reported [1] a static checker warning that ctx->offsets[]
may be accessed off by one from build_body(), since it's allocated with
fp->len * sizeof(*ctx.offsets) as length. The cBPF arm and ppc code
doesn't have this issue as claimed, so only mips seems to be affected and
should like most other JITs allocate with fp->len + 1. A few number of
JITs (x86, sparc, arm64) handle this differently, where they only require
fp->len array elements.

  [1] http://www.spinics.net/lists/mips/msg64193.html

Fixes: c6610de353da ("MIPS: net: Add BPF JIT")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: ast@kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13814/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/net/bpf_jit.c