Date: Mon, 29 Aug 2022 07:15:15 +0000
From: HAGIO KAZUHITO(?????)  <k-hagio-ab@nec.com>
To: "Discussion list for crash utility usage, maintenance and
        development" <crash-utility@redhat.com>, Tao Liu <ltao@redhat.com>
Subject: Re: [Crash-utility] [PATCH v2] Add ending identifier for
        union when parsing task structure
Message-ID: <b5f22630-9649-20a2-6233-f229f76353dc@nec.com>
Content-Type: text/plain; charset="utf-8"

On 2022/08/25 15:39, Tao Liu wrote:
> Previously, the start and end identifier for union is "  {\n"
> and "  }, \n". However the end identifier is not always as
> expected. "  },\n" can also be the end identifier. As a result,
> variable "randomized" is in incorrect state after union, and
> fails to identify the later struct members. For example, we can
> reproduce the issue as follows:
>
>      crash> task
>      PID: 847      TASK: ffff94f8038f4000  CPU: 72   COMMAND: "khungtaskd"
>      struct task_struct {
>        thread_info = {
>       flags = 2148024320,
>       status = 0,
>       preempt_lazy_count = 0
>        },
>        {
>       <the union>
>        },
>        ...
>        wake_entry = {
>       next = 0x0
>        },
>        ...
>
> Before patch:
>
>      crash> task -R wake_entry
>      PID: 847      TASK: ffff94f8038f4000  CPU: 72   COMMAND: "khungtaskd"
>
> After patch:
>
>      crash> task -R wake_entry
>      PID: 847      TASK: ffff94f8038f4000  CPU: 72   COMMAND: "khungtaskd"
>        wake_entry = {
>       next = 0x0
>        },
>
> Signed-off-by: Tao Liu <ltao@redhat.com>
> ---
>
> v1 -> v2: Rewrite the commit log.

Thanks for the update.

I will add "with gdb-10.2" to the commit log when applying.

Acked-by: Kazuhito Hagio <k-hagio-ab@nec.com>

Thanks,
Kazu


>
> ---
>   task.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/task.c b/task.c
> index 071c787..db2abc8 100644
> --- a/task.c
> +++ b/task.c
> @@ -3436,7 +3436,8 @@ parse_task_thread(int argcnt, char *arglist[], struct task_context *tc) {
>           while (fgets(buf, BUFSIZE, pc->tmpfile)) {
>               if (STREQ(buf, "  {\n"))
>                       randomized = TRUE;
> -             else if (randomized && STREQ(buf, "  }, \n"))
> +             else if (randomized &&
> +                      (STREQ(buf, "  }, \n") || STREQ(buf, "  },\n")))

>                       randomized = FALSE;
>   
>               if (strlen(lookfor2)) {