diff options
| author | German Gomez <german.gomez@arm.com> | 2021-12-01 12:33:29 +0000 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-12-11 08:19:46 -0300 |
| commit | c897899752478d4c905c56f2b54b99ba82b34e13 (patch) | |
| tree | e0ccdf9e72abe14007e7c6ae84773c2bb1492e30 /tools/perf | |
| parent | 6f513529296fd4f696afb4354c46508abe646541 (diff) | |
| download | linux-c897899752478d4c905c56f2b54b99ba82b34e13.tar.bz2 | |
perf tools: Prevent out-of-bounds access to registers
The size of the cache of register values is arch-dependant
(PERF_REGS_MAX). This has the potential of causing an out-of-bounds
access in the function "perf_reg_value" if the local architecture
contains less registers than the one the perf.data file was recorded on.
Since the maximum number of registers is bound by the bitmask "u64
cache_mask", and the size of the cache when running under x86 systems is
64 already, fix the size to 64 and add a range-check to the function
"perf_reg_value" to prevent out-of-bounds access.
Reported-by: Alexandre Truong <alexandre.truong@arm.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: German Gomez <german.gomez@arm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-csky@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20211201123334.679131-2-german.gomez@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
| -rw-r--r-- | tools/perf/util/event.h | 5 | ||||
| -rw-r--r-- | tools/perf/util/perf_regs.c | 3 |
2 files changed, 7 insertions, 1 deletions
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 95ffed66369c..c59331eea1d9 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -44,13 +44,16 @@ struct perf_event_attr; /* perf sample has 16 bits size limit */ #define PERF_SAMPLE_MAX_SIZE (1 << 16) +/* number of register is bound by the number of bits in regs_dump::mask (64) */ +#define PERF_SAMPLE_REGS_CACHE_SIZE (8 * sizeof(u64)) + struct regs_dump { u64 abi; u64 mask; u64 *regs; /* Cached values/mask filled by first register access. */ - u64 cache_regs[PERF_REGS_MAX]; + u64 cache_regs[PERF_SAMPLE_REGS_CACHE_SIZE]; u64 cache_mask; }; diff --git a/tools/perf/util/perf_regs.c b/tools/perf/util/perf_regs.c index 5ee47ae1509c..06a7461ba864 100644 --- a/tools/perf/util/perf_regs.c +++ b/tools/perf/util/perf_regs.c @@ -25,6 +25,9 @@ int perf_reg_value(u64 *valp, struct regs_dump *regs, int id) int i, idx = 0; u64 mask = regs->mask; + if ((u64)id >= PERF_SAMPLE_REGS_CACHE_SIZE) + return -EINVAL; + if (regs->cache_mask & (1ULL << id)) goto out; |