tomoyo: recognize kernel threads correctly

commit 9c83465f3245c2faa82ffeb7016f40f02bfaa0ad upstream.

Commit db68ce10c4 ("new helper: uaccess_kernel()") replaced
segment_eq(get_fs(), KERNEL_DS) with uaccess_kernel(). But the correct
method for tomoyo to check whether current is a kernel thread in order
to assume that kernel threads are privileged for socket operations was
(current->flags & PF_KTHREAD). Now that uaccess_kernel() became 0 on x86,
tomoyo has to fix this problem. Do like commit 942cb357ae7d9249 ("Smack:
Handle io_uring kernel thread privileges") does.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tetsuo Handa 2021-02-01 11:53:05 +09:00 committed by Greg Kroah-Hartman
parent 4645271c32
commit aa40f5e33c

View File

@ -613,7 +613,7 @@ static int tomoyo_check_unix_address(struct sockaddr *addr,
static bool tomoyo_kernel_service(void)
{
/* Nothing to do if I am a kernel service. */
return uaccess_kernel();
return (current->flags & (PF_KTHREAD | PF_IO_WORKER)) == PF_KTHREAD;
}
/**