Re: [PATCH] perf arm-spe: Avoid potential buffer overrun.

[Arnaldo Carvalho de Melo]

Em Wed, Apr 07, 2021 at 08:39:55AM -0700, Ian Rogers escreveu:
> SPE extended headers are >1 byte so ensure the buffer contains at
> least this before reading. This issue was detected by fuzzing.

Thanks, applied.

- Arnaldo

 
> Signed-off-by: Ian Rogers <irog...@google.com>
> ---
>  tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c 
> b/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c
> index f3ac9d40cebf..2e5eff4f8f03 100644
> --- a/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c
> +++ b/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c
> @@ -210,8 +210,10 @@ static int arm_spe_do_get_packet(const unsigned char 
> *buf, size_t len,
>  
>       if ((hdr & SPE_HEADER0_MASK2) == SPE_HEADER0_EXTENDED) {
>               /* 16-bit extended format header */
> -             ext_hdr = 1;
> +             if (len == 1)
> +                     return ARM_SPE_BAD_PACKET;
>  
> +             ext_hdr = 1;
>               hdr = buf[1];
>               if (hdr == SPE_HEADER1_ALIGNMENT)
>                       return arm_spe_get_alignment(buf, len, packet);
> -- 
> 2.31.0.208.g409f899ff0-goog
> 

-- 

- Arnaldo