xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

BACKPORT: sched: Fix yet more sched_fork() races

Browse Source 
Where commit 4ef0c5c6b5ba ("kernel/sched: Fix sched_fork() access an
invalid sched_task_group") fixed a fork race vs cgroup, it opened up a
race vs syscalls by not placing the task on the runqueue before it
gets exposed through the pidhash.

Commit 13765de8148f ("sched/fair: Fix fault in reweight_entity") is
trying to fix a single instance of this, instead fix the whole class
of issues, effectively reverting this commit.

Change-Id: If8d8fc38f2ab1334c45e530aaaedfc7b2825a7e5
Fixes: 4ef0c5c6b5ba ("kernel/sched: Fix sched_fork() access an invalid sched_task_group")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Tested-by: Zhang Qiao <zhangqiao22@huawei.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/YgoeCbwj5mbCR0qA@hirez.programming.kicks-ass.net
BUG: 221793230
(cherry picked from commit b1e8206582f9d680cff7d04828708c8b6ab32957)
[quic_ashayj: Resolved minor merge conflicts]
Signed-off-by: Ashay Jaiswal <quic_ashayj@quicinc.com>
This commit is contained in:
Peter Zijlstra
2022-02-14 10:16:57 +01:00
committed by Todd Kjos
parent cd6e5d5d7d
commit 8248a3e758
3 changed files with 36 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
include/linux/sched/task.h
View File

@@ -55,8 +55,8 @@ extern asmlinkage void schedule_tail(struct task_struct *prev);
extern void init_idle(struct task_struct *idle, int cpu);
extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
extern void sched_post_fork(struct task_struct *p,
struct kernel_clone_args *kargs);
extern void sched_cgroup_fork(struct task_struct *p, struct kernel_clone_args *kargs);
extern void sched_post_fork(struct task_struct *p);
extern void sched_dead(struct task_struct *p);
void __noreturn do_task_dead(void);