From f3c2682bad7bc6033c837e9c66e5af881fe8d465 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Tue, 1 Mar 2022 20:22:39 +0100 Subject: random: provide notifier for VM fork Drivers such as WireGuard need to learn when VMs fork in order to clear sessions. This commit provides a simple notifier_block for that, with a register and unregister function. When no VM fork detection is compiled in, this turns into a no-op, similar to how the power notifier works. Cc: Dominik Brodowski Cc: Theodore Ts'o Reviewed-by: Greg Kroah-Hartman Signed-off-by: Jason A. Donenfeld --- include/linux/random.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/random.h') diff --git a/include/linux/random.h b/include/linux/random.h index fab1ab0563b4..c0baffe7afb1 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -32,6 +32,11 @@ extern void add_hwgenerator_randomness(const void *buffer, size_t count, size_t entropy); #if IS_ENABLED(CONFIG_VMGENID) extern void add_vmfork_randomness(const void *unique_vm_id, size_t size); +extern int register_random_vmfork_notifier(struct notifier_block *nb); +extern int unregister_random_vmfork_notifier(struct notifier_block *nb); +#else +static inline int register_random_vmfork_notifier(struct notifier_block *nb) { return 0; } +static inline int unregister_random_vmfork_notifier(struct notifier_block *nb) { return 0; } #endif extern void get_random_bytes(void *buf, size_t nbytes); -- cgit v1.2.3