[PATCH linux-next] perf annotate: use strscpy() is more robust and safer

[PATCH linux-next] perf annotate: use strscpy() is more robust and safer

[cgel.zte]

From: ye xingchen <ye.xingchen@zte.com.cn>

The implementation of strscpy() is more robust and safer.

That's now the recommended way to copy NUL terminated strings.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
---
 tools/perf/util/annotate.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 5bc63c9e0324..e2b038b14ff6 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1702,7 +1702,7 @@ static int dso__disassemble_filename(struct dso *dso, char *filename, size_t fil
 			char *new_name = filename_with_chroot(dso->nsinfo->pid,
 							      filename);
 			if (new_name) {
-				strlcpy(filename, new_name, filename_size);
+				strscpy(filename, new_name, filename_size);
 				free(new_name);
 			}
 		}
@@ -2002,7 +2002,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args)
 		kce.len = sym->end - sym->start;
 		if (!kcore_extract__create(&kce)) {
 			delete_extract = true;
-			strlcpy(symfs_filename, kce.extract_filename,
+			strscpy(symfs_filename, kce.extract_filename,
 				sizeof(symfs_filename));
 		}
 	} else if (dso__needs_decompress(dso)) {
-- 
2.25.1

Re: [PATCH linux-next] perf annotate: use strscpy() is more robust and safer

[Arnaldo Carvalho de Melo]

Em Thu, Sep 22, 2022 at 01:24:31AM +0000, cgel.zte@gmail.com escreveu:
> From: ye xingchen <ye.xingchen@zte.com.cn>
> 
> The implementation of strscpy() is more robust and safer.

Where is strscpy() defined?

I see it defined in the kernel:

⬢[acme@toolbox perf]$ grep -w strscpy include/linux/string.h
ssize_t strscpy(char *, const char *, size_t);
/* Wraps calls to strscpy()/memset(), no arch specific code required */
⬢[acme@toolbox perf]$

But not in tools/

Have you actually build with these patches?

- Arnaldo
 
> That's now the recommended way to copy NUL terminated strings.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
> ---
>  tools/perf/util/annotate.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 5bc63c9e0324..e2b038b14ff6 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -1702,7 +1702,7 @@ static int dso__disassemble_filename(struct dso *dso, char *filename, size_t fil
>  			char *new_name = filename_with_chroot(dso->nsinfo->pid,
>  							      filename);
>  			if (new_name) {
> -				strlcpy(filename, new_name, filename_size);
> +				strscpy(filename, new_name, filename_size);
>  				free(new_name);
>  			}
>  		}
> @@ -2002,7 +2002,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args)
>  		kce.len = sym->end - sym->start;
>  		if (!kcore_extract__create(&kce)) {
>  			delete_extract = true;
> -			strlcpy(symfs_filename, kce.extract_filename,
> +			strscpy(symfs_filename, kce.extract_filename,
>  				sizeof(symfs_filename));
>  		}
>  	} else if (dso__needs_decompress(dso)) {
> -- 
> 2.25.1

-- 

- Arnaldo