From 05585e449572d7bdb798a87a732f86760c6b3c77 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 20 Mar 2018 19:33:48 +0100 Subject: [PATCH] fs: add do_compat_select() helper; remove in-kernel call to compat syscall Using the fs-internal do_compat_select() helper allows us to get rid of the fs-internal call to the compat_sys_select() syscall. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro Cc: Andrew Morton Signed-off-by: Dominik Brodowski --- fs/select.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/select.c b/fs/select.c index b5df01c4587d..ba879c51288f 100644 --- a/fs/select.c +++ b/fs/select.c @@ -1265,9 +1265,9 @@ out_nofds: return ret; } -COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp, - compat_ulong_t __user *, outp, compat_ulong_t __user *, exp, - struct compat_timeval __user *, tvp) +static int do_compat_select(int n, compat_ulong_t __user *inp, + compat_ulong_t __user *outp, compat_ulong_t __user *exp, + struct compat_timeval __user *tvp) { struct timespec64 end_time, *to = NULL; struct compat_timeval tv; @@ -1290,6 +1290,13 @@ COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp, return ret; } +COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp, + compat_ulong_t __user *, outp, compat_ulong_t __user *, exp, + struct compat_timeval __user *, tvp) +{ + return do_compat_select(n, inp, outp, exp, tvp); +} + struct compat_sel_arg_struct { compat_ulong_t n; compat_uptr_t inp; @@ -1304,8 +1311,8 @@ COMPAT_SYSCALL_DEFINE1(old_select, struct compat_sel_arg_struct __user *, arg) if (copy_from_user(&a, arg, sizeof(a))) return -EFAULT; - return compat_sys_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp), - compat_ptr(a.exp), compat_ptr(a.tvp)); + return do_compat_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp), + compat_ptr(a.exp), compat_ptr(a.tvp)); } static long do_compat_pselect(int n, compat_ulong_t __user *inp, -- 2.30.2