diff options
| -rw-r--r-- | include/uapi/linux/sched.h | 3 | ||||
| -rw-r--r-- | kernel/fork.c | 16 |
2 files changed, 14 insertions, 5 deletions
diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h index 99335e1f4a27..1d500ed03c63 100644 --- a/include/uapi/linux/sched.h +++ b/include/uapi/linux/sched.h @@ -33,6 +33,9 @@ #define CLONE_NEWNET 0x40000000 /* New network namespace */ #define CLONE_IO 0x80000000 /* Clone io context */ +/* Flags for the clone3() syscall. */ +#define CLONE_CLEAR_SIGHAND 0x100000000ULL /* Clear any signal handler and reset to SIG_DFL. */ + #ifndef __ASSEMBLY__ /** * struct clone_args - arguments for the clone3 syscall diff --git a/kernel/fork.c b/kernel/fork.c index ffa314838b43..954e875e72b1 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1517,6 +1517,11 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk) spin_lock_irq(¤t->sighand->siglock); memcpy(sig->action, current->sighand->action, sizeof(sig->action)); spin_unlock_irq(¤t->sighand->siglock); + + /* Reset all signal handler not set to SIG_IGN to SIG_DFL. */ + if (clone_flags & CLONE_CLEAR_SIGHAND) + flush_signal_handlers(tsk, 0); + return 0; } @@ -2619,11 +2624,8 @@ noinline static int copy_clone_args_from_user(struct kernel_clone_args *kargs, static bool clone3_args_valid(const struct kernel_clone_args *kargs) { - /* - * All lower bits of the flag word are taken. - * Verify that no other unknown flags are passed along. - */ - if (kargs->flags & ~CLONE_LEGACY_FLAGS) + /* Verify that no unknown flags are passed along. */ + if (kargs->flags & ~(CLONE_LEGACY_FLAGS | CLONE_CLEAR_SIGHAND)) return false; /* @@ -2633,6 +2635,10 @@ static bool clone3_args_valid(const struct kernel_clone_args *kargs) if (kargs->flags & (CLONE_DETACHED | CSIGNAL)) return false; + if ((kargs->flags & (CLONE_SIGHAND | CLONE_CLEAR_SIGHAND)) == + (CLONE_SIGHAND | CLONE_CLEAR_SIGHAND)) + return false; + if ((kargs->flags & (CLONE_THREAD | CLONE_PARENT)) && kargs->exit_signal) return false; |