2015-05-14 12:23:36

by Wang Nan

Subject: [PATCH] tools perf: set vmlinux_path__nr_entries to 0 in vmlinux_path__exit.

Original vmlinux_path__exit() doesn't revert vmlinux_path__nr_entries
to its original state. After the while loop vmlinux_path__nr_entries
becomes -1 instead of 0. This makes a problem that, if runs twice,
during the second run vmlinux_path__init() will set vmlinux_path[-1]
to strdup("vmlinux"), corrupts random memory.

This patch reset vmlinux_path__nr_entries to 0 after the while loop.

Signed-off-by: Wang Nan <[email protected]>
---
tools/perf/util/symbol.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 201f6c4c..451777f 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1802,6 +1802,7 @@ static void vmlinux_path__exit(void)
{
while (--vmlinux_path__nr_entries >= 0)
zfree(&vmlinux_path[vmlinux_path__nr_entries]);
+ vmlinux_path__nr_entries = 0;

zfree(&vmlinux_path);
}
--
1.8.3.4

2015-05-15 02:27:20

by Namhyung Kim

Subject: Re: [PATCH] tools perf: set vmlinux_path__nr_entries to 0 in vmlinux_path__exit.

Hello,

On Thu, May 14, 2015 at 12:22:30PM +0000, Wang Nan wrote:
> Original vmlinux_path__exit() doesn't revert vmlinux_path__nr_entries
> to its original state. After the while loop vmlinux_path__nr_entries
> becomes -1 instead of 0. This makes a problem that, if runs twice,
> during the second run vmlinux_path__init() will set vmlinux_path[-1]
> to strdup("vmlinux"), corrupts random memory.
>
> This patch reset vmlinux_path__nr_entries to 0 after the while loop.
>
> Signed-off-by: Wang Nan <[email protected]>

Acked-by: Namhyung Kim <[email protected]>

Thanks,
Namhyung


> ---
> tools/perf/util/symbol.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 201f6c4c..451777f 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1802,6 +1802,7 @@ static void vmlinux_path__exit(void)
> {
> while (--vmlinux_path__nr_entries >= 0)
> zfree(&vmlinux_path[vmlinux_path__nr_entries]);
> + vmlinux_path__nr_entries = 0;
>
> zfree(&vmlinux_path);
> }
> --
> 1.8.3.4
>
> --
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