diff options
| author | Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | 2023-01-02 10:12:16 -0500 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2023-01-02 16:34:12 +0100 |
| commit | bbd0b031509b880b4e9a880bb27ca2a30ad081ab (patch) | |
| tree | 3c16b06a9c0bc653348674cbc9dd5b743897f660 | |
| parent | c89970202a1153b2fc230e89f90c180bd5bcbcef (diff) | |
sched/rseq: Fix concurrency ID handling of usermodehelper kthreads
sched_mm_cid_after_execve() does not expect NULL t->mm, but it may happen
if a usermodehelper kthread fails when attempting to execute a binary.
sched_mm_cid_fork() can be issued from a usermodehelper kthread, which
has t->flags PF_KTHREAD set.
Fixes: af7f588d8f73 ("sched: Introduce per-memory-map concurrency ID")
Reported-by: kernel test robot <yujie.liu@intel.com>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/oe-lkp/202212301353.5c959d72-yujie.liu@intel.com
| -rw-r--r-- | kernel/sched/core.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 048ec2417990..f99ee69867e3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -11343,8 +11343,8 @@ void sched_mm_cid_after_execve(struct task_struct *t) struct mm_struct *mm = t->mm; unsigned long flags; - WARN_ON_ONCE((t->flags & PF_KTHREAD) || !t->mm); - + if (!mm) + return; local_irq_save(flags); t->mm_cid = mm_cid_get(mm); t->mm_cid_active = 1; @@ -11354,7 +11354,7 @@ void sched_mm_cid_after_execve(struct task_struct *t) void sched_mm_cid_fork(struct task_struct *t) { - WARN_ON_ONCE((t->flags & PF_KTHREAD) || !t->mm || t->mm_cid != -1); + WARN_ON_ONCE(!t->mm || t->mm_cid != -1); t->mm_cid_active = 1; } #endif |