[tip:x86/entry] x86/syscalls: Use the compat versions of rt_sigsuspend() and rt_sigprocmask()

From: tip-bot for Andy Lutomirski
Date: Mon Jul 22 2019 - 04:35:01 EST


Commit-ID: a8d03c3f300eefff3b5c14798409e4b43e37dd9b
Gitweb: https://git.kernel.org/tip/a8d03c3f300eefff3b5c14798409e4b43e37dd9b
Author: Andy Lutomirski <luto@xxxxxxxxxx>
AuthorDate: Wed, 3 Jul 2019 13:34:02 -0700
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Mon, 22 Jul 2019 10:31:22 +0200

x86/syscalls: Use the compat versions of rt_sigsuspend() and rt_sigprocmask()

I'm working on some code that detects at build time if there's a
COMPAT_SYSCALL_DEFINE() that is not referenced in the x86 syscall tables.
It catches three offenders: rt_sigsuspend(), rt_sigprocmask(), and
sendfile64().

For rt_sigsuspend() and rt_sigprocmask(), the only potential difference
between the native and compat versions is that the compat version converts
the sigset_t, but, on little endian architectures, the conversion is a
no-op. This is why they both currently work on x86.

To make the code more consistent, and to make the upcoming patches work,
rewire x86 to use the compat vesions.

sendfile64() is more complicated, and will be addressed separately.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/51643ac3157b5921eae0e172a8a0b1d953e68ebb.1562185330.git.luto@xxxxxxxxxx

---
arch/x86/entry/syscalls/syscall_32.tbl | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index c00019abd076..3fe02546aed3 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -186,11 +186,11 @@
172 i386 prctl sys_prctl __ia32_sys_prctl
173 i386 rt_sigreturn sys_rt_sigreturn sys32_rt_sigreturn
174 i386 rt_sigaction sys_rt_sigaction __ia32_compat_sys_rt_sigaction
-175 i386 rt_sigprocmask sys_rt_sigprocmask __ia32_sys_rt_sigprocmask
+175 i386 rt_sigprocmask sys_rt_sigprocmask __ia32_compat_sys_rt_sigprocmask
176 i386 rt_sigpending sys_rt_sigpending __ia32_compat_sys_rt_sigpending
177 i386 rt_sigtimedwait sys_rt_sigtimedwait_time32 __ia32_compat_sys_rt_sigtimedwait_time32
178 i386 rt_sigqueueinfo sys_rt_sigqueueinfo __ia32_compat_sys_rt_sigqueueinfo
-179 i386 rt_sigsuspend sys_rt_sigsuspend __ia32_sys_rt_sigsuspend
+179 i386 rt_sigsuspend sys_rt_sigsuspend __ia32_compat_sys_rt_sigsuspend
180 i386 pread64 sys_pread64 __ia32_compat_sys_x86_pread
181 i386 pwrite64 sys_pwrite64 __ia32_compat_sys_x86_pwrite
182 i386 chown sys_chown16 __ia32_sys_chown16