From: gushengxian <[email protected]>
Some memory leak issues should be fixed by free().
Reported by cppcheck.
Signed-off-by: gushengxian <[email protected]>
---
tools/perf/arch/arm/tests/dwarf-unwind.c | 1 +
tools/perf/arch/arm64/tests/dwarf-unwind.c | 1 +
tools/perf/arch/powerpc/tests/dwarf-unwind.c | 1 +
tools/perf/arch/x86/tests/dwarf-unwind.c | 1 +
4 files changed, 4 insertions(+)
diff --git a/tools/perf/arch/arm/tests/dwarf-unwind.c b/tools/perf/arch/arm/tests/dwarf-unwind.c
index ccfa87055c4a..f2541d1dbb02 100644
--- a/tools/perf/arch/arm/tests/dwarf-unwind.c
+++ b/tools/perf/arch/arm/tests/dwarf-unwind.c
@@ -39,6 +39,7 @@ static int sample_ustack(struct perf_sample *sample,
memcpy(buf, (void *) sp, stack_size);
stack->data = (char *) buf;
stack->size = stack_size;
+ free(buf);
return 0;
}
diff --git a/tools/perf/arch/arm64/tests/dwarf-unwind.c b/tools/perf/arch/arm64/tests/dwarf-unwind.c
index 46147a483049..ecd25c77a71f 100644
--- a/tools/perf/arch/arm64/tests/dwarf-unwind.c
+++ b/tools/perf/arch/arm64/tests/dwarf-unwind.c
@@ -39,6 +39,7 @@ static int sample_ustack(struct perf_sample *sample,
memcpy(buf, (void *) sp, stack_size);
stack->data = (char *) buf;
stack->size = stack_size;
+ free(buf);
return 0;
}
diff --git a/tools/perf/arch/powerpc/tests/dwarf-unwind.c b/tools/perf/arch/powerpc/tests/dwarf-unwind.c
index 8efd9ed9e9db..e57a8ca52ce7 100644
--- a/tools/perf/arch/powerpc/tests/dwarf-unwind.c
+++ b/tools/perf/arch/powerpc/tests/dwarf-unwind.c
@@ -40,6 +40,7 @@ static int sample_ustack(struct perf_sample *sample,
memcpy(buf, (void *) sp, stack_size);
stack->data = (char *) buf;
stack->size = stack_size;
+ free(buf);
return 0;
}
diff --git a/tools/perf/arch/x86/tests/dwarf-unwind.c b/tools/perf/arch/x86/tests/dwarf-unwind.c
index 478078fb0f22..da90b33a1e28 100644
--- a/tools/perf/arch/x86/tests/dwarf-unwind.c
+++ b/tools/perf/arch/x86/tests/dwarf-unwind.c
@@ -47,6 +47,7 @@ static int sample_ustack(struct perf_sample *sample,
#endif
stack->data = (char *) buf;
stack->size = stack_size;
+ free(buf);
return 0;
}
--
2.25.1
Em Thu, Jul 01, 2021 at 09:09:55PM -0700, gushengxian escreveu:
> From: gushengxian <[email protected]>
>
> Some memory leak issues should be fixed by free().
> Reported by cppcheck.
Thanks, applied.
- Arnaldo
> Signed-off-by: gushengxian <[email protected]>
> ---
> tools/perf/arch/arm/tests/dwarf-unwind.c | 1 +
> tools/perf/arch/arm64/tests/dwarf-unwind.c | 1 +
> tools/perf/arch/powerpc/tests/dwarf-unwind.c | 1 +
> tools/perf/arch/x86/tests/dwarf-unwind.c | 1 +
> 4 files changed, 4 insertions(+)
>
> diff --git a/tools/perf/arch/arm/tests/dwarf-unwind.c b/tools/perf/arch/arm/tests/dwarf-unwind.c
> index ccfa87055c4a..f2541d1dbb02 100644
> --- a/tools/perf/arch/arm/tests/dwarf-unwind.c
> +++ b/tools/perf/arch/arm/tests/dwarf-unwind.c
> @@ -39,6 +39,7 @@ static int sample_ustack(struct perf_sample *sample,
> memcpy(buf, (void *) sp, stack_size);
> stack->data = (char *) buf;
> stack->size = stack_size;
> + free(buf);
> return 0;
> }
>
> diff --git a/tools/perf/arch/arm64/tests/dwarf-unwind.c b/tools/perf/arch/arm64/tests/dwarf-unwind.c
> index 46147a483049..ecd25c77a71f 100644
> --- a/tools/perf/arch/arm64/tests/dwarf-unwind.c
> +++ b/tools/perf/arch/arm64/tests/dwarf-unwind.c
> @@ -39,6 +39,7 @@ static int sample_ustack(struct perf_sample *sample,
> memcpy(buf, (void *) sp, stack_size);
> stack->data = (char *) buf;
> stack->size = stack_size;
> + free(buf);
> return 0;
> }
>
> diff --git a/tools/perf/arch/powerpc/tests/dwarf-unwind.c b/tools/perf/arch/powerpc/tests/dwarf-unwind.c
> index 8efd9ed9e9db..e57a8ca52ce7 100644
> --- a/tools/perf/arch/powerpc/tests/dwarf-unwind.c
> +++ b/tools/perf/arch/powerpc/tests/dwarf-unwind.c
> @@ -40,6 +40,7 @@ static int sample_ustack(struct perf_sample *sample,
> memcpy(buf, (void *) sp, stack_size);
> stack->data = (char *) buf;
> stack->size = stack_size;
> + free(buf);
> return 0;
> }
>
> diff --git a/tools/perf/arch/x86/tests/dwarf-unwind.c b/tools/perf/arch/x86/tests/dwarf-unwind.c
> index 478078fb0f22..da90b33a1e28 100644
> --- a/tools/perf/arch/x86/tests/dwarf-unwind.c
> +++ b/tools/perf/arch/x86/tests/dwarf-unwind.c
> @@ -47,6 +47,7 @@ static int sample_ustack(struct perf_sample *sample,
> #endif
> stack->data = (char *) buf;
> stack->size = stack_size;
> + free(buf);
> return 0;
> }
>
> --
> 2.25.1
>
--
- Arnaldo
Hi Arnaldo,
On Fri, Jul 02, 2021 at 09:58:52AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Thu, Jul 01, 2021 at 09:09:55PM -0700, gushengxian escreveu:
> > From: gushengxian <[email protected]>
> >
> > Some memory leak issues should be fixed by free().
> > Reported by cppcheck.
I don't think this patch does the right thing. You could see that the
memory is allocated in arch specific function sample_ustack(), and the
"buf" pointer is assigned to sample->user_stack.data; and the memory
actually is released in the caller function test_dwarf_unwind__thread:
noinline int test_dwarf_unwind__thread(struct thread *thread)
{
struct perf_sample sample;
unsigned long cnt = 0;
int err = -1;
memset(&sample, 0, sizeof(sample));
if (test__arch_unwind_sample(&sample, thread)) {
pr_debug("failed to get unwind sample\n");
goto out;
}
[...]
out:
zfree(&sample.user_stack.data);
zfree(&sample.user_regs.regs);
return err;
}
So this patch will break the testing and doesn't fix any memory leak
issue.
Thanks,
Leo
Em Fri, Jul 02, 2021 at 09:56:41PM +0800, Leo Yan escreveu:
> Hi Arnaldo,
>
> On Fri, Jul 02, 2021 at 09:58:52AM -0300, Arnaldo Carvalho de Melo wrote:
> > Em Thu, Jul 01, 2021 at 09:09:55PM -0700, gushengxian escreveu:
> > > From: gushengxian <[email protected]>
> > >
> > > Some memory leak issues should be fixed by free().
> > > Reported by cppcheck.
>
> I don't think this patch does the right thing. You could see that the
> memory is allocated in arch specific function sample_ustack(), and the
> "buf" pointer is assigned to sample->user_stack.data; and the memory
> actually is released in the caller function test_dwarf_unwind__thread:
>
> noinline int test_dwarf_unwind__thread(struct thread *thread)
> {
> struct perf_sample sample;
> unsigned long cnt = 0;
> int err = -1;
>
> memset(&sample, 0, sizeof(sample));
>
> if (test__arch_unwind_sample(&sample, thread)) {
> pr_debug("failed to get unwind sample\n");
> goto out;
> }
>
> [...]
>
> out:
> zfree(&sample.user_stack.data);
> zfree(&sample.user_regs.regs);
> return err;
> }
>
> So this patch will break the testing and doesn't fix any memory leak
> issue.
You are right, those buffers are allocated in those functions and then
_returned_ via sample->user_stack, the tool (and myself, ugh) got
fooled, I'll remove that from my local tree.
Thanks Leo!
- Arnaldo