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From:   Christoph Hellwig <hch@lst.de>
To:     Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>
Cc:     Jeremy Kerr <jk@ozlabs.org>, Arnd Bergmann <arnd@arndb.de>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH 2/8] signal: clean up __copy_siginfo_to_user32
Date:   Tue, 14 Apr 2020 09:01:36 +0200
Message-Id: <20200414070142.288696-3-hch@lst.de>
In-Reply-To: <20200414070142.288696-1-hch@lst.de>
References: <20200414070142.288696-1-hch@lst.de>
MIME-Version: 1.0
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Sender: linux-kernel-owner@vger.kernel.org
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Instead of an architecture specific calling convention in common code
just pass a flags argument with architecture specific values.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/x86/ia32/ia32_signal.c   |  2 +-
 arch/x86/include/asm/compat.h |  4 ----
 arch/x86/include/asm/signal.h |  3 +++
 arch/x86/kernel/signal.c      |  3 ++-
 include/linux/compat.h        |  2 ++
 kernel/signal.c               | 21 ++++++++++++---------
 6 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index f9d8804144d0..2bf188942d5c 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -350,7 +350,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
 	unsafe_put_user(*(__u64 *)set, (__u64 *)&frame->uc.uc_sigmask, Efault);
 	user_access_end();
 
-	if (__copy_siginfo_to_user32(&frame->info, &ksig->info, false))
+	if (__copy_siginfo_to_user32(&frame->info, &ksig->info, SA_IA32_ABI))
 		return -EFAULT;
 
 	/* Set up registers for signal handler */
diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h
index 52e9f3480f69..a787c9a82030 100644
--- a/arch/x86/include/asm/compat.h
+++ b/arch/x86/include/asm/compat.h
@@ -213,8 +213,4 @@ static inline bool in_compat_syscall(void)
 #define in_compat_syscall in_compat_syscall	/* override the generic impl */
 #endif
 
-struct compat_siginfo;
-int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
-		const kernel_siginfo_t *from, bool x32_ABI);
-
 #endif /* _ASM_X86_COMPAT_H */
diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h
index 33d3c88a7225..b3f7a14da428 100644
--- a/arch/x86/include/asm/signal.h
+++ b/arch/x86/include/asm/signal.h
@@ -28,6 +28,9 @@ typedef struct {
 #define SA_IA32_ABI	0x02000000u
 #define SA_X32_ABI	0x01000000u
 
+#define compat_siginfo_flags() \
+	(in_x32_syscall() ? SA_X32_ABI : SA_IA32_ABI)
+
 #ifndef CONFIG_COMPAT
 typedef sigset_t compat_sigset_t;
 #endif
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 83b74fb38c8f..bbd451631790 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -543,7 +543,8 @@ static int x32_setup_rt_frame(struct ksignal *ksig,
 	user_access_end();
 
 	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
-		if (__copy_siginfo_to_user32(&frame->info, &ksig->info, true))
+		if (__copy_siginfo_to_user32(&frame->info, &ksig->info,
+				SA_X32_ABI))
 			return -EFAULT;
 	}
 
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 0480ba4db592..14eec6116110 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -404,6 +404,8 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 		       unsigned long bitmap_size);
 int copy_siginfo_from_user32(kernel_siginfo_t *to, const struct compat_siginfo __user *from);
 int copy_siginfo_to_user32(struct compat_siginfo __user *to, const kernel_siginfo_t *from);
+int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
+		const kernel_siginfo_t *from, unsigned int flags);
 int get_compat_sigevent(struct sigevent *event,
 		const struct compat_sigevent __user *u_event);
 
diff --git a/kernel/signal.c b/kernel/signal.c
index e58a6c619824..092fee008242 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3235,15 +3235,8 @@ int copy_siginfo_from_user(kernel_siginfo_t *to, const siginfo_t __user *from)
 }
 
 #ifdef CONFIG_COMPAT
-int copy_siginfo_to_user32(struct compat_siginfo __user *to,
-			   const struct kernel_siginfo *from)
-#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION)
-{
-	return __copy_siginfo_to_user32(to, from, in_x32_syscall());
-}
 int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
-			     const struct kernel_siginfo *from, bool x32_ABI)
-#endif
+		const struct kernel_siginfo *from, unsigned int flags)
 {
 	struct compat_siginfo new;
 	memset(&new, 0, sizeof(new));
@@ -3298,7 +3291,7 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
 		new.si_uid    = from->si_uid;
 		new.si_status = from->si_status;
 #ifdef CONFIG_X86_X32_ABI
-		if (x32_ABI) {
+		if (flags & SA_X32_ABI) {
 			new._sifields._sigchld_x32._utime = from->si_utime;
 			new._sifields._sigchld_x32._stime = from->si_stime;
 		} else
@@ -3326,6 +3319,16 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
 	return 0;
 }
 
+#ifndef compat_siginfo_flags
+#define compat_siginfo_flags()		0
+#endif
+
+int copy_siginfo_to_user32(struct compat_siginfo __user *to,
+			   const struct kernel_siginfo *from)
+{
+	return __copy_siginfo_to_user32(to, from, compat_siginfo_flags());
+}
+
 static int post_copy_siginfo_from_user32(kernel_siginfo_t *to,
 					 const struct compat_siginfo *from)
 {
-- 
2.25.1