bpf: task_group_seq_get_next: use __next_thread() rather than next_thread()

Browse source

Lockless use of next_thread() should be avoided, kernel/bpf/task_iter.c
is the last user and the usage is wrong.

task_group_seq_get_next() can return the group leader twice if it races
with mt-thread exec which changes the group->leader's pid.

Change the main loop to use __next_thread(), kill "next_tid == common->pid"
check.

__next_thread() can't loop forever, we can also change this code to retry
if next_tid == 0.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231114163234.GA890@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

...

This commit is contained in:

Oleg Nesterov 2023-11-14 17:32:34 +01:00 • committed by Alexei Starovoitov

parent 16b3129e14

commit 2d1618054f

1 changed files with 5 additions and 7 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

12

kernel/bpf/task_iter.c

View file