From: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Date: Thu, 22 Jan 2026 17:17:04 +0000 (+0530)
Subject: perf annotate: Fix memcpy size in arch__grow_instructions()
X-Git-Tag: v7.0-rc1~16^2~129
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f0d98c78f8bf73ce2a9b7793f66cda240fa9ab10;p=thirdparty%2Flinux.git

perf annotate: Fix memcpy size in arch__grow_instructions()

The memcpy() in arch__grow_instructions() is copying the wrong number of
bytes when growing from a non-allocated table.

It should copy arch->nr_instructions * sizeof(struct ins) bytes, not
just arch->nr_instructions bytes.

This bug causes data corruption as only a partial copy of the
instruction table is made, leading to garbage data in most entries and
potential crashes

Fixes: 2a1ff812c40be982 ("perf annotate: Introduce alternative method of keeping instructions table")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/util/disasm.c b/tools/perf/util/disasm.c
index 4f60726247d6..9b0ba1fc5aec 100644
--- a/tools/perf/util/disasm.c
+++ b/tools/perf/util/disasm.c
@@ -82,7 +82,7 @@ grow_from_non_allocated_table:
 	if (new_instructions == NULL)
 		return -1;
 
-	memcpy(new_instructions, arch->instructions, arch->nr_instructions);
+	memcpy(new_instructions, arch->instructions, arch->nr_instructions * sizeof(struct ins));
 	goto out_update_instructions;
 }