如何找到是否启用了CONFIG_FANOTIFY_ACCESS_PERMISSIONS ?

I want to make use of fanotify(7) and the problem I run into is that on some kernels CONFIG_FANOTIFY_ACCESS_PERMISSIONS does not work, although CONFIG_FANOTIFY is configured.

我想使用fanotify(7)，我遇到的问题是，在一些内核CONFIG_FANOTIFY_ACCESS_PERMISSIONS不能工作，尽管配置了CONFIG_FANOTIFY，但仍然存在这个问题。

At the very least I'd like to report this condition.

至少我想报告一下这个情况。

Now on Debian and Ubuntu I could use the equivalent of grep CONFIG_FANOTIFY_ACCESS_PERMISSIONS /boot/config-$(uname -r) to verify that the feature is available. On some other systems I could use the equivalent of zgrep CONFIG_FANOTIFY_ACCESS_PERMISSIONS /proc/config.gz, but there are probably some more systems that are not covered by these two methods.

现在，在Debian和Ubuntu上，我可以使用grep CONFIG_FANOTIFY_ACCESS_PERMISSIONS /boot/config-$(uname -r)来验证该特性是否可用。在其他一些系统上，我可以使用等效的zgrep CONFIG_FANOTIFY_ACCESS_PERMISSIONS / proc/config/ config。gz，但是可能还有更多的系统没有被这两种方法覆盖。

Is there a way to figure out in any of the fanotify(7) functions whether or not fanotify permission handling is available on the kernel currently running?

是否有一种方法可以在任何一个fanotify(7)函数中找到，在当前运行的内核中是否可以使用fanotify权限处理?

I was thinking of a method similar to the returned ENOSYS when fanotify_mark() is not implemented (fanotify_mark(2)), but could not find anything like that in the documentation.

当fanotify_mark()没有实现(fanotify_mark(2))时，我想到了一个类似于返回的ENOSYS的方法，但是在文档中找不到类似的东西。

1 个解决方案

#1

It seems that fanotify_mark() returns EINVAL when FAN_ALL_PERM_EVENTS is passed but CONFIG_FANOTIFY_ACCESS_PERMISSIONS is disabled.

似乎在传递FAN_ALL_PERM_EVENTS时，fanotify_mark()返回EINVAL，但禁用了CONFIG_FANOTIFY_ACCESS_PERMISSIONS。

See fs/notify/fanotify/fanotify_user.c in kernel sources:

看到fs /通知/ fanotify / fanotify_user。c在内核来源:

SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
                              __u64, mask, int, dfd,
                              const char  __user *, pathname)
{
...

#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
        if (mask & ~(FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD))
#else
        if (mask & ~(FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD))
#endif
                return -EINVAL;

#1