[PATCH] perf annotate: Use jump__delete when freeing LoongArch jumps
From: Rong Bao
Date: Sun Apr 12 2026 - 02:50:52 EST
Currently, the initialization of loongarch_jump_ops does not contain an
assignment to its .free field. This causes disasm_line__free() to fall
through to ins_ops__delete() for LoongArch jump instructions.
ins_ops__delete() will free ins_operands.source.raw and
ins_operands.source.name, and these fields overlaps with
ins_operands.jump.raw_comment and ins_operands.jump.raw_func_start.
Since in loongarch_jump__parse(), these two fields are populated by
strchr()-ing the same buffer, trying to free them will lead to undefined
behavior.
This invalid free usually leads to crashes:
Process 1712902 (perf) of user 1000 dumped core.
Stack trace of thread 1712902:
#0 0x00007fffef155c58 n/a (libc.so.6 + 0x95c58)
#1 0x00007fffef0f7a94 raise (libc.so.6 + 0x37a94)
#2 0x00007fffef0dd6a8 abort (libc.so.6 + 0x1d6a8)
#3 0x00007fffef145490 n/a (libc.so.6 + 0x85490)
#4 0x00007fffef1646f4 n/a (libc.so.6 + 0xa46f4)
#5 0x00007fffef164718 n/a (libc.so.6 + 0xa4718)
#6 0x00005555583a6764 __zfree (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x106764)
#7 0x000055555854fb70 disasm_line__free (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x2afb70)
#8 0x000055555853d618 annotated_source__purge (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x29d618)
#9 0x000055555852300c __hist_entry__tui_annotate (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x28300c)
#10 0x0000555558526718 do_annotate (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x286718)
#11 0x000055555852ed94 evsel__hists_browse (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x28ed94)
#12 0x000055555831fdd0 cmd_report (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x7fdd0)
#13 0x000055555839b644 handle_internal_command (/home/csmantle/dist/linux-arch/tools/perf/perf + 0xfb644)
#14 0x00005555582fe6ac main (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x5e6ac)
#15 0x00007fffef0ddd90 n/a (libc.so.6 + 0x1dd90)
#16 0x00007fffef0ddf0c __libc_start_main (libc.so.6 + 0x1df0c)
#17 0x00005555582fed10 _start (/home/csmantle/dist/linux-arch/tools/perf/perf + 0x5ed10)
ELF object binary architecture: LoongArch
... and it can be confirmed with Valgrind:
==1721834== Invalid free() / delete / delete[] / realloc()
==1721834== at 0x4EA9014: free (in /usr/lib/valgrind/vgpreload_memcheck-loongarch64-linux.so)
==1721834== by 0x4106287: __zfree (zalloc.c:13)
==1721834== by 0x42ADC8F: disasm_line__free (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x429B737: annotated_source__purge (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42811EB: __hist_entry__tui_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42848D7: do_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x428CF33: evsel__hists_browse (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== Address 0x7d34303 is 35 bytes inside a block of size 62 alloc'd
==1721834== at 0x4EA59B8: malloc (in /usr/lib/valgrind/vgpreload_memcheck-loongarch64-linux.so)
==1721834== by 0x6B80B6F: strdup (strdup.c:42)
==1721834== by 0x42AD917: disasm_line__new (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42AE5A3: symbol__disassemble_objdump (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42AF0A7: symbol__disassemble (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x429B3CF: symbol__annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x429C233: symbol__annotate2 (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42804D3: __hist_entry__tui_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x42848D7: do_annotate (in /home/csmantle/dist/linux-arch/tools/perf/perf)
==1721834== by 0x428CF33: evsel__hists_browse (in /home/csmantle/dist/linux-arch/tools/perf/perf)
This patch adds the missing free() specialization in loongarch_jump_ops,
which prevents disasm_line__free() from invoking the default cleanup
function.
Fixes: 4ca0d340ce206 ("perf annotate: Fix instruction association and parsing for LoongArch")
Cc: stable@xxxxxxxxxxxxxxx
Cc: WANG Rui <wangrui@xxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: WANG Xuerui <kernel@xxxxxxxxxx>
Cc: loongarch@xxxxxxxxxxxxxxx
Signed-off-by: Rong Bao <rong.bao@xxxxxxxxxxxx>
---
tools/perf/util/annotate-arch/annotate-loongarch.c | 1 +
tools/perf/util/disasm.c | 2 +-
tools/perf/util/disasm.h | 1 +
3 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/annotate-arch/annotate-loongarch.c b/tools/perf/util/annotate-arch/annotate-loongarch.c
index 950f34e59e5cd..c2addca77320b 100644
--- a/tools/perf/util/annotate-arch/annotate-loongarch.c
+++ b/tools/perf/util/annotate-arch/annotate-loongarch.c
@@ -110,6 +110,7 @@ static int loongarch_jump__parse(const struct arch *arch, struct ins_operands *o
}
static const struct ins_ops loongarch_jump_ops = {
+ .free = jump__delete,
.parse = loongarch_jump__parse,
.scnprintf = jump__scnprintf,
.is_jump = true,
diff --git a/tools/perf/util/disasm.c b/tools/perf/util/disasm.c
index 9e0420e14be19..62bd8c3e53051 100644
--- a/tools/perf/util/disasm.c
+++ b/tools/perf/util/disasm.c
@@ -451,7 +451,7 @@ int jump__scnprintf(const struct ins *ins, char *bf, size_t size,
ops->target.offset);
}
-static void jump__delete(struct ins_operands *ops __maybe_unused)
+void jump__delete(struct ins_operands *ops __maybe_unused)
{
/*
* The ops->jump.raw_comment and ops->jump.raw_func_start belong to the
diff --git a/tools/perf/util/disasm.h b/tools/perf/util/disasm.h
index a6e478caf61a9..6b7fef3bbc42f 100644
--- a/tools/perf/util/disasm.h
+++ b/tools/perf/util/disasm.h
@@ -158,6 +158,7 @@ int call__scnprintf(const struct ins *ins, char *bf, size_t size,
struct ins_operands *ops, int max_ins_name);
int jump__scnprintf(const struct ins *ins, char *bf, size_t size,
struct ins_operands *ops, int max_ins_name);
+void jump__delete(struct ins_operands *ops);
int mov__scnprintf(const struct ins *ins, char *bf, size_t size,
struct ins_operands *ops, int max_ins_name);
base-commit: f5459048c38a00fc583658d6dcd0f894aff6df8f
--
2.53.0