2024-05-14 05:24:20

by Ian Rogers

Subject: [PATCH v1] perf arm-spe: Unaligned pointer work around

Use get_unaligned_leXX instead of leXX_to_cpu to handle unaligned
pointers. Such pointers occur with libFuzzer testing.

A similar change for intel-pt was done in:
https://lore.kernel.org/r/[email protected]

Signed-off-by: Ian Rogers <[email protected]>
---
.../arm-spe-decoder/arm-spe-pkt-decoder.c | 23 ++++---------------
1 file changed, 5 insertions(+), 18 deletions(-)

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 a454c6737563..7bf607d0f6d8 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
@@ -10,24 +10,11 @@
#include <byteswap.h>
#include <linux/bitops.h>
#include <stdarg.h>
+#include <linux/kernel.h>
+#include <asm-generic/unaligned.h>

#include "arm-spe-pkt-decoder.h"

-#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-#define le16_to_cpu bswap_16
-#define le32_to_cpu bswap_32
-#define le64_to_cpu bswap_64
-#define memcpy_le64(d, s, n) do { \
- memcpy((d), (s), (n)); \
- *(d) = le64_to_cpu(*(d)); \
-} while (0)
-#else
-#define le16_to_cpu
-#define le32_to_cpu
-#define le64_to_cpu
-#define memcpy_le64 memcpy
-#endif
-
static const char * const arm_spe_packet_name[] = {
[ARM_SPE_PAD] = "PAD",
[ARM_SPE_END] = "END",
@@ -70,9 +57,9 @@ static int arm_spe_get_payload(const unsigned char *buf, size_t len,

switch (payload_len) {
case 1: packet->payload = *(uint8_t *)buf; break;
- case 2: packet->payload = le16_to_cpu(*(uint16_t *)buf); break;
- case 4: packet->payload = le32_to_cpu(*(uint32_t *)buf); break;
- case 8: packet->payload = le64_to_cpu(*(uint64_t *)buf); break;
+ case 2: packet->payload = get_unaligned_le16(buf); break;
+ case 4: packet->payload = get_unaligned_le32(buf); break;
+ case 8: packet->payload = get_unaligned_le64(buf); break;
default: return ARM_SPE_BAD_PACKET;
}

--
2.45.0.rc1.225.g2a3ae87e7f-goog

2024-05-14 15:40:37

by Ian Rogers

Subject: Re: [PATCH v1] perf arm-spe: Unaligned pointer work around

On Mon, May 13, 2024 at 10:24 PM Ian Rogers <[email protected]> wrote:
>
> Use get_unaligned_leXX instead of leXX_to_cpu to handle unaligned
> pointers. Such pointers occur with libFuzzer testing.
>
> A similar change for intel-pt was done in:
> https://lore.kernel.org/r/[email protected]
>
> Signed-off-by: Ian Rogers <[email protected]>

+Leo Yan +James Clark surprisingly missed by get_maintainer.pl.

Thanks,
Ian

> ---
> .../arm-spe-decoder/arm-spe-pkt-decoder.c | 23 ++++---------------
> 1 file changed, 5 insertions(+), 18 deletions(-)
>
> 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 a454c6737563..7bf607d0f6d8 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
> @@ -10,24 +10,11 @@
> #include <byteswap.h>
> #include <linux/bitops.h>
> #include <stdarg.h>
> +#include <linux/kernel.h>
> +#include <asm-generic/unaligned.h>
>
> #include "arm-spe-pkt-decoder.h"
>
> -#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> -#define le16_to_cpu bswap_16
> -#define le32_to_cpu bswap_32
> -#define le64_to_cpu bswap_64
> -#define memcpy_le64(d, s, n) do { \
> - memcpy((d), (s), (n)); \
> - *(d) = le64_to_cpu(*(d)); \
> -} while (0)
> -#else
> -#define le16_to_cpu
> -#define le32_to_cpu
> -#define le64_to_cpu
> -#define memcpy_le64 memcpy
> -#endif
> -
> static const char * const arm_spe_packet_name[] = {
> [ARM_SPE_PAD] = "PAD",
> [ARM_SPE_END] = "END",
> @@ -70,9 +57,9 @@ static int arm_spe_get_payload(const unsigned char *buf, size_t len,
>
> switch (payload_len) {
> case 1: packet->payload = *(uint8_t *)buf; break;
> - case 2: packet->payload = le16_to_cpu(*(uint16_t *)buf); break;
> - case 4: packet->payload = le32_to_cpu(*(uint32_t *)buf); break;
> - case 8: packet->payload = le64_to_cpu(*(uint64_t *)buf); break;
> + case 2: packet->payload = get_unaligned_le16(buf); break;
> + case 4: packet->payload = get_unaligned_le32(buf); break;
> + case 8: packet->payload = get_unaligned_le64(buf); break;
> default: return ARM_SPE_BAD_PACKET;
> }
>
> --
> 2.45.0.rc1.225.g2a3ae87e7f-goog
>

2024-05-15 15:38:38

by James Clark

Subject: Re: [PATCH v1] perf arm-spe: Unaligned pointer work around

On 14/05/2024 07:24, Ian Rogers wrote:
> Use get_unaligned_leXX instead of leXX_to_cpu to handle unaligned
> pointers. Such pointers occur with libFuzzer testing.
>
> A similar change for intel-pt was done in:
> https://lore.kernel.org/r/[email protected]
>
> Signed-off-by: Ian Rogers <[email protected]>
> ---

Reviewed-by: James Clark <[email protected]>

> .../arm-spe-decoder/arm-spe-pkt-decoder.c | 23 ++++---------------
> 1 file changed, 5 insertions(+), 18 deletions(-)
>
> 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 a454c6737563..7bf607d0f6d8 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
> @@ -10,24 +10,11 @@
> #include <byteswap.h>
> #include <linux/bitops.h>
> #include <stdarg.h>
> +#include <linux/kernel.h>
> +#include <asm-generic/unaligned.h>
>
> #include "arm-spe-pkt-decoder.h"
>
> -#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> -#define le16_to_cpu bswap_16
> -#define le32_to_cpu bswap_32
> -#define le64_to_cpu bswap_64
> -#define memcpy_le64(d, s, n) do { \
> - memcpy((d), (s), (n)); \
> - *(d) = le64_to_cpu(*(d)); \
> -} while (0)
> -#else
> -#define le16_to_cpu
> -#define le32_to_cpu
> -#define le64_to_cpu
> -#define memcpy_le64 memcpy
> -#endif
> -
> static const char * const arm_spe_packet_name[] = {
> [ARM_SPE_PAD] = "PAD",
> [ARM_SPE_END] = "END",
> @@ -70,9 +57,9 @@ static int arm_spe_get_payload(const unsigned char *buf, size_t len,
>
> switch (payload_len) {
> case 1: packet->payload = *(uint8_t *)buf; break;
> - case 2: packet->payload = le16_to_cpu(*(uint16_t *)buf); break;
> - case 4: packet->payload = le32_to_cpu(*(uint32_t *)buf); break;
> - case 8: packet->payload = le64_to_cpu(*(uint64_t *)buf); break;
> + case 2: packet->payload = get_unaligned_le16(buf); break;
> + case 4: packet->payload = get_unaligned_le32(buf); break;
> + case 8: packet->payload = get_unaligned_le64(buf); break;
> default: return ARM_SPE_BAD_PACKET;
> }
>

2024-05-29 19:25:31

by Namhyung Kim

Subject: Re: [PATCH v1] perf arm-spe: Unaligned pointer work around

On Mon, 13 May 2024 22:24:02 -0700, Ian Rogers wrote:
> Use get_unaligned_leXX instead of leXX_to_cpu to handle unaligned
> pointers. Such pointers occur with libFuzzer testing.
>
> A similar change for intel-pt was done in:
> https://lore.kernel.org/r/[email protected]
>
>
> [...]

Applied to perf-tools-next, thanks!

Best regards,
--
Namhyung Kim <[email protected]>