Re: [PATCH v3 04/21] perf annotate-arm64: Generalize arm64_mov__parse to support more instructions

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The parsing logic permanently corrupts the raw instruction string buffer (`ops->raw`) when restoring the `<` character after extracting a source symbol name.
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commit 13742d589ccf5a86dcfd0991f541a8f1d46f7e0f
Author: Tengda Wu <wutengda@huaweicloud.com>

perf annotate-arm64: Generalize arm64_mov__parse to support more instructions

This commit generalizes arm64_mov__parse() to parse source and target operands
for a wider variety of arm64 instructions. It utilizes arm64__check_multi_regs()
to identify multiple registers while attempting to preserve parsing behavior for
instructions containing the addr <symbol> suffix.

> diff --git a/tools/perf/util/annotate-arch/annotate-arm64.c b/tools/perf/util/annotate-arch/annotate-arm64.c
> index 33080fdca125f..a1667237114a6 100644
> --- a/tools/perf/util/annotate-arch/annotate-arm64.c
> +++ b/tools/perf/util/annotate-arch/annotate-arm64.c

[ ... ]

> @@ -14,59 +16,129 @@
>  static int arm64_mov__parse(const struct arch *arch,
>  			    struct ins_operands *ops,
>  			    struct map_symbol *ms __maybe_unused,
>  			    struct disasm_line *dl __maybe_unused)
>  {

[ ... ]

> +	/* Parse a symbol followed by an address, if present */
>  	s = strchr(endptr, '<');
>  	if (s == NULL)
> -		goto out_free_target;
> -	endptr = strchr(s + 1, '>');
> +		return 0;
> +	endptr = strrchr(s + 1, '>');
>  	if (endptr == NULL)
> -		goto out_free_target;
> +		return 0;
>  
>  	*endptr = '\0';
>  	*s = ' ';
> -	ops->target.name = strdup(s);
> +	s = skip_spaces(++s);
> +	ops->source.name = strdup(s);
>  	*s = '<';
>  	*endptr = '>';

[Severity: Medium]
Does this code overwrite the first character of the symbol name?

Because s is advanced by skip_spaces(++s), s now points to the first character
of the symbol name. When *s = '<' is executed immediately after, it appears to
corrupt the ops->raw instruction string buffer instead of restoring the '<'
character at its original position. 

This could result in a visual glitch in the fallback raw instruction view
where the first character of the symbol name is overwritten (for example,
0x1000 <sym> becomes 0x1000  <ym>).

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Sashiko AI review · https://sashiko.dev/#/patchset/20260701035355.752944-1-wutengda@huaweicloud.com?part=4