]> git.ipfire.org Git - thirdparty/kernel/linux.git/commitdiff
perf annotate: Use jump__delete when freeing LoongArch jumps
authorRong Bao <rong.bao@csmantle.top>
Mon, 13 Apr 2026 10:03:55 +0000 (18:03 +0800)
committerNamhyung Kim <namhyung@kernel.org>
Tue, 14 Apr 2026 06:41:11 +0000 (23:41 -0700)
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: fb7fd2a14a503b9a ("perf annotate: Move raw_comment and raw_func_start fields out of 'struct ins_operands'")
Cc: stable@vger.kernel.org
Cc: WANG Rui <wangrui@loongson.cn>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: loongarch@lists.linux.dev
Signed-off-by: Rong Bao <rong.bao@csmantle.top>
Tested-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
tools/perf/util/annotate-arch/annotate-loongarch.c
tools/perf/util/disasm.c
tools/perf/util/disasm.h

index 950f34e59e5cd926cfa0fbf04bfe3fd00abc47d0..c2addca77320bea760dbd65a5441c5c3097705fa 100644 (file)
@@ -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,
index 4f5bd915355242ec7d4f7990b83169be08042aa2..59ba88e1f7443c027aa2badbc06339723a9172cc 100644 (file)
@@ -452,7 +452,7 @@ 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
index a6e478caf61a95857e86e1154dbef6d2a2078447..25756e3f47e47240edf254fc46442320c1d85fa8 100644 (file)
@@ -161,6 +161,8 @@ int jump__scnprintf(const struct ins *ins, char *bf, size_t size,
 int mov__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 symbol__disassemble(struct symbol *sym, struct annotate_args *args);
 
 char *expand_tabs(char *line, char **storage, size_t *storage_len);