From 92f1e8adf7db2ef9b90e5662182810c0cf8ac22e Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Wed, 7 Apr 2021 08:39:55 -0700 Subject: perf arm-spe: Avoid potential buffer overrun SPE extended headers are > 1 byte so ensure the buffer contains at least this before reading. This issue was detected by fuzzing. Signed-off-by: Ian Rogers Cc: Alexander Shishkin Cc: Andre Przywara Cc: Dave Martin Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Will Deacon Link: http://lore.kernel.org/lkml/20210407153955.317215-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'tools/perf') 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); -- cgit v1.2.3