2019-10-16 12:59:43

by Yunfeng Ye

[permalink] [raw]
Subject: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()

The memory @orig_flags is allocated by strdup(), it is freed on the
normal path, but leak to free on the error path.

Fix this by adding free(orig_flags) on the error path.

Signed-off-by: Yunfeng Ye <[email protected]>
---
tools/perf/builtin-kmem.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index 1e61e353f579..9661671cc26e 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
new = realloc(new_flags, len + strlen(cpt) + 2);
if (new == NULL) {
free(new_flags);
+ free(orig_flags);
return NULL;
}

--
2.7.4.3


2019-10-16 16:01:50

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: Re: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()

Em Wed, Oct 16, 2019 at 04:38:45PM +0800, Yunfeng Ye escreveu:
> The memory @orig_flags is allocated by strdup(), it is freed on the
> normal path, but leak to free on the error path.

Are you using some tool to find out these problems? Or is it just visual
inspection?

- Arnaldo

> Fix this by adding free(orig_flags) on the error path.
>
> Signed-off-by: Yunfeng Ye <[email protected]>
> ---
> tools/perf/builtin-kmem.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
> index 1e61e353f579..9661671cc26e 100644
> --- a/tools/perf/builtin-kmem.c
> +++ b/tools/perf/builtin-kmem.c
> @@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
> new = realloc(new_flags, len + strlen(cpt) + 2);
> if (new == NULL) {
> free(new_flags);
> + free(orig_flags);
> return NULL;
> }
>
> --
> 2.7.4.3

--

- Arnaldo

2019-10-16 16:04:02

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: Re: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()

Em Wed, Oct 16, 2019 at 10:04:03AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Wed, Oct 16, 2019 at 04:38:45PM +0800, Yunfeng Ye escreveu:
> > The memory @orig_flags is allocated by strdup(), it is freed on the
> > normal path, but leak to free on the error path.
>
> Are you using some tool to find out these problems? Or is it just visual
> inspection?

Anyway, applied after adding this to the commit log message:

Fixes: 0e11115644b3 ("perf kmem: Print gfp flags in human readable string")

- Arnaldo

> - Arnaldo
>
> > Fix this by adding free(orig_flags) on the error path.
> >
> > Signed-off-by: Yunfeng Ye <[email protected]>
> > ---
> > tools/perf/builtin-kmem.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
> > index 1e61e353f579..9661671cc26e 100644
> > --- a/tools/perf/builtin-kmem.c
> > +++ b/tools/perf/builtin-kmem.c
> > @@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
> > new = realloc(new_flags, len + strlen(cpt) + 2);
> > if (new == NULL) {
> > free(new_flags);
> > + free(orig_flags);
> > return NULL;
> > }
> >
> > --
> > 2.7.4.3
>
> --
>
> - Arnaldo

--

- Arnaldo

2019-10-16 16:05:05

by Yunfeng Ye

[permalink] [raw]
Subject: Re: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()



On 2019/10/16 21:09, Arnaldo Carvalho de Melo wrote:
> Em Wed, Oct 16, 2019 at 10:04:03AM -0300, Arnaldo Carvalho de Melo escreveu:
>> Em Wed, Oct 16, 2019 at 04:38:45PM +0800, Yunfeng Ye escreveu:
>>> The memory @orig_flags is allocated by strdup(), it is freed on the
>>> normal path, but leak to free on the error path.
>>
>> Are you using some tool to find out these problems? Or is it just visual
>> inspection?
>
By a static code anaylsis tool which not an open source tool. thanks.

> Anyway, applied after adding this to the commit log message:
>
> Fixes: 0e11115644b3 ("perf kmem: Print gfp flags in human readable string")
>
ok, thanks.

> - Arnaldo
>
>> - Arnaldo
>>
>>> Fix this by adding free(orig_flags) on the error path.
>>>
>>> Signed-off-by: Yunfeng Ye <[email protected]>
>>> ---
>>> tools/perf/builtin-kmem.c | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
>>> index 1e61e353f579..9661671cc26e 100644
>>> --- a/tools/perf/builtin-kmem.c
>>> +++ b/tools/perf/builtin-kmem.c
>>> @@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
>>> new = realloc(new_flags, len + strlen(cpt) + 2);
>>> if (new == NULL) {
>>> free(new_flags);
>>> + free(orig_flags);
>>> return NULL;
>>> }
>>>
>>> --
>>> 2.7.4.3
>>
>> --
>>
>> - Arnaldo
>

2019-10-16 16:15:08

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: Re: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()

Em Wed, Oct 16, 2019 at 09:19:54PM +0800, Yunfeng Ye escreveu:
>
>
> On 2019/10/16 21:09, Arnaldo Carvalho de Melo wrote:
> > Em Wed, Oct 16, 2019 at 10:04:03AM -0300, Arnaldo Carvalho de Melo escreveu:
> >> Em Wed, Oct 16, 2019 at 04:38:45PM +0800, Yunfeng Ye escreveu:
> >>> The memory @orig_flags is allocated by strdup(), it is freed on the
> >>> normal path, but leak to free on the error path.
> >>
> >> Are you using some tool to find out these problems? Or is it just visual
> >> inspection?
> >
> By a static code anaylsis tool which not an open source tool. thanks.

Ok, so please state that next time, just for the fullest possible
disclosure and for people to realize to what extent problems in the
kernel and in tooling hosted in the kernel is being fixed by such tools.

I.e. you don't need to release the tool, not even give out its name,
just something like:

"Found by internal static analysis tool."

Thanks,

- Arnaldo

> > Anyway, applied after adding this to the commit log message:
> >
> > Fixes: 0e11115644b3 ("perf kmem: Print gfp flags in human readable string")
> >
> ok, thanks.
>
> > - Arnaldo
> >
> >> - Arnaldo
> >>
> >>> Fix this by adding free(orig_flags) on the error path.
> >>>
> >>> Signed-off-by: Yunfeng Ye <[email protected]>
> >>> ---
> >>> tools/perf/builtin-kmem.c | 1 +
> >>> 1 file changed, 1 insertion(+)
> >>>
> >>> diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
> >>> index 1e61e353f579..9661671cc26e 100644
> >>> --- a/tools/perf/builtin-kmem.c
> >>> +++ b/tools/perf/builtin-kmem.c
> >>> @@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
> >>> new = realloc(new_flags, len + strlen(cpt) + 2);
> >>> if (new == NULL) {
> >>> free(new_flags);
> >>> + free(orig_flags);
> >>> return NULL;
> >>> }
> >>>
> >>> --
> >>> 2.7.4.3
> >>
> >> --
> >>
> >> - Arnaldo
> >

--

- Arnaldo

2019-10-16 16:19:18

by Yunfeng Ye

[permalink] [raw]
Subject: Re: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()



On 2019/10/16 22:08, Arnaldo Carvalho de Melo wrote:
> Em Wed, Oct 16, 2019 at 09:19:54PM +0800, Yunfeng Ye escreveu:
>>
>>
>> On 2019/10/16 21:09, Arnaldo Carvalho de Melo wrote:
>>> Em Wed, Oct 16, 2019 at 10:04:03AM -0300, Arnaldo Carvalho de Melo escreveu:
>>>> Em Wed, Oct 16, 2019 at 04:38:45PM +0800, Yunfeng Ye escreveu:
>>>>> The memory @orig_flags is allocated by strdup(), it is freed on the
>>>>> normal path, but leak to free on the error path.
>>>>
>>>> Are you using some tool to find out these problems? Or is it just visual
>>>> inspection?
>>>
>> By a static code anaylsis tool which not an open source tool. thanks.
>
> Ok, so please state that next time, just for the fullest possible
> disclosure and for people to realize to what extent problems in the
> kernel and in tooling hosted in the kernel is being fixed by such tools.
>
> I.e. you don't need to release the tool, not even give out its name,
> just something like:
>
> "Found by internal static analysis tool."
>
ok, thanks.

> Thanks,
>
> - Arnaldo
>
>>> Anyway, applied after adding this to the commit log message:
>>>
>>> Fixes: 0e11115644b3 ("perf kmem: Print gfp flags in human readable string")
>>>
>> ok, thanks.
>>
>>> - Arnaldo
>>>
>>>> - Arnaldo
>>>>
>>>>> Fix this by adding free(orig_flags) on the error path.
>>>>>
>>>>> Signed-off-by: Yunfeng Ye <[email protected]>
>>>>> ---
>>>>> tools/perf/builtin-kmem.c | 1 +
>>>>> 1 file changed, 1 insertion(+)
>>>>>
>>>>> diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
>>>>> index 1e61e353f579..9661671cc26e 100644
>>>>> --- a/tools/perf/builtin-kmem.c
>>>>> +++ b/tools/perf/builtin-kmem.c
>>>>> @@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
>>>>> new = realloc(new_flags, len + strlen(cpt) + 2);
>>>>> if (new == NULL) {
>>>>> free(new_flags);
>>>>> + free(orig_flags);
>>>>> return NULL;
>>>>> }
>>>>>
>>>>> --
>>>>> 2.7.4.3
>>>>
>>>> --
>>>>
>>>> - Arnaldo
>>>
>

Subject: [tip: perf/urgent] perf kmem: Fix memory leak in compact_gfp_flags()

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID: 1abecfcaa7bba21c9985e0136fa49836164dd8fd
Gitweb: https://git.kernel.org/tip/1abecfcaa7bba21c9985e0136fa49836164dd8fd
Author: Yunfeng Ye <[email protected]>
AuthorDate: Wed, 16 Oct 2019 16:38:45 +08:00
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitterDate: Wed, 16 Oct 2019 10:08:32 -03:00

perf kmem: Fix memory leak in compact_gfp_flags()

The memory @orig_flags is allocated by strdup(), it is freed on the
normal path, but leak to free on the error path.

Fix this by adding free(orig_flags) on the error path.

Fixes: 0e11115644b3 ("perf kmem: Print gfp flags in human readable string")
Signed-off-by: Yunfeng Ye <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Feilong Lin <[email protected]>
Cc: Hu Shiyuan <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/builtin-kmem.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index 1e61e35..9661671 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
new = realloc(new_flags, len + strlen(cpt) + 2);
if (new == NULL) {
free(new_flags);
+ free(orig_flags);
return NULL;
}