Re: [Crash-utility] [PATCH v2] Add ending identifier for union when parsing task structure
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(a)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(a)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)) {