Re: [PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

From: Arnaldo Carvalho de Melo
Date: Tue Jul 28 2020 - 08:10:49 EST


Em Fri, Jul 24, 2020 at 06:07:06PM +0800, Wang ShaoBo escreveu:
> Function jvmti_write_code called by compiled_method_load_cb may return
> error in using fwrite_unlocked, this failure should be captured and
> warned.

Thanks, applied.

- Arnaldo

> Signed-off-by: Wang ShaoBo <bobo.shaobowang@xxxxxxxxxx>
> ---
> tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
> 1 file changed, 15 insertions(+), 8 deletions(-)
>
> diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
> index 88108598d6e9..a1fe6aa16b6d 100644
> --- a/tools/perf/jvmti/jvmti_agent.c
> +++ b/tools/perf/jvmti/jvmti_agent.c
> @@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
> struct jr_code_load rec;
> size_t sym_len;
> FILE *fp = agent;
> - int ret = -1;
> + int ret;
>
> /* don't care about 0 length function, no samples */
> if (size == 0)
> @@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
> rec.code_index = code_generation++;
>
> ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
> - fwrite_unlocked(sym, sym_len, 1, fp);
> + if (ret)
> + goto error;
> + ret = fwrite_unlocked(sym, sym_len, 1, fp);
> + if (ret)
> + goto error;
>
> - if (code)
> - fwrite_unlocked(code, size, 1, fp);
> + if (code) {
> + ret = fwrite_unlocked(code, size, 1, fp);
> + if (ret)
> + goto error;
> + }
>
> funlockfile(fp);
> -
> - ret = 0;
> -
> - return ret;
> + return 0;
> +error:
> + funlockfile(fp);
> + return -1;
> }
>
> int
> --
> 2.17.1
>

--

- Arnaldo