From: Adrian Hunter <adrian.hunter@intel.com>
Date: Thu, 16 Mar 2023 21:41:55 +0200
Subject: [PATCH] perf symbols: Fix unaligned access in get_x86_64_plt_disp()
References: bsc#1012628
Patch-mainline: 6.3.3
Git-commit: a2410b579c72242ac0f77b3768093d8c1b48012e
[ Upstream commit a2410b579c72242ac0f77b3768093d8c1b48012e ]
Use memcpy() to avoid unaligned access.
Discovered using EXTRA_CFLAGS="-fsanitize=undefined -fsanitize=address".
Fixes: ce4c8e7966f317ef ("perf symbols: Get symbols for .plt.got for x86-64")
Reported-by: kernel test robot <yujie.liu@intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/oe-lkp/202303061424.6ad43294-yujie.liu@intel.com
Link: https://lore.kernel.org/r/20230316194156.8320-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
tools/perf/util/symbol-elf.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 98a18fb8..42b83bef 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -565,9 +565,12 @@ static u32 get_x86_64_plt_disp(const u8 *p)
n += 1;
/* jmp with 4-byte displacement */
if (p[n] == 0xff && p[n + 1] == 0x25) {
+ u32 disp;
+
n += 2;
/* Also add offset from start of entry to end of instruction */
- return n + 4 + le32toh(*(const u32 *)(p + n));
+ memcpy(&disp, p + n, sizeof(disp));
+ return n + 4 + le32toh(disp);
}
return 0;
}
--
2.35.3