From 4c48abe91be03d191d0c20cc755877da2cb35622 Mon Sep 17 00:00:00 2001 From: Al Viro <viro@zeniv.linux.org.uk> Date: Sun, 14 May 2017 19:27:32 -0400 Subject: [PATCH] waitid(): switch copyout of siginfo to unsafe_put_user() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> --- kernel/exit.c | 40 +++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-) diff --git a/kernel/exit.c b/kernel/exit.c index 97db9ee03f9012..f3b8c3a87bc197 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1625,15 +1625,18 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *, if (!infop) return err; - if (put_user(err ? 0 : SIGCHLD, &infop->si_signo) || - put_user(0, &infop->si_errno) || - put_user((short)info.cause, &infop->si_code) || - put_user(info.pid, &infop->si_pid) || - put_user(info.uid, &infop->si_uid) || - put_user(info.status, &infop->si_status)) - err = -EFAULT; - + user_access_begin(); + unsafe_put_user(err ? 0 : SIGCHLD, &infop->si_signo, Efault); + unsafe_put_user(0, &infop->si_errno, Efault); + unsafe_put_user((short)info.cause, &infop->si_code, Efault); + unsafe_put_user(info.pid, &infop->si_pid, Efault); + unsafe_put_user(info.uid, &infop->si_uid, Efault); + unsafe_put_user(info.status, &infop->si_status, Efault); + user_access_end(); return err; +Efault: + user_access_end(); + return -EFAULT; } static long kernel_wait4(pid_t upid, int __user *stat_addr, @@ -1736,13 +1739,20 @@ COMPAT_SYSCALL_DEFINE5(waitid, return -EFAULT; } - if (put_user(err ? 0 : SIGCHLD, &infop->si_signo) || - put_user(0, &infop->si_errno) || - put_user((short)info.cause, &infop->si_code) || - put_user(info.pid, &infop->si_pid) || - put_user(info.uid, &infop->si_uid) || - put_user(info.status, &infop->si_status)) - err = -EFAULT; + if (!infop) + return err; + + user_access_begin(); + unsafe_put_user(err ? 0 : SIGCHLD, &infop->si_signo, Efault); + unsafe_put_user(0, &infop->si_errno, Efault); + unsafe_put_user((short)info.cause, &infop->si_code, Efault); + unsafe_put_user(info.pid, &infop->si_pid, Efault); + unsafe_put_user(info.uid, &infop->si_uid, Efault); + unsafe_put_user(info.status, &infop->si_status, Efault); + user_access_end(); return err; +Efault: + user_access_end(); + return -EFAULT; } #endif -- GitLab