diff mbox series

[3/8] signal: replace __copy_siginfo_to_user32 with to_compat_siginfo

Message ID 20200414070142.288696-4-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [1/8] powerpc/spufs: simplify spufs core dumping | expand

Commit Message

Christoph Hellwig April 14, 2020, 7:01 a.m. UTC 
Move copying the siginfo to userspace into the callers, so that the
compat_siginfo conversion can be reused by the ELF coredump code without
set_fs magic.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/x86/ia32/ia32_signal.c |  4 +-
 arch/x86/kernel/signal.c    |  5 ++-
 include/linux/compat.h      |  4 +-
 kernel/signal.c             | 89 ++++++++++++++++++-------------------
 4 files changed, 52 insertions(+), 50 deletions(-)

Comments

Arnd Bergmann April 14, 2020, 2 p.m. UTC | #1 
On Tue, Apr 14, 2020 at 9:01 AM Christoph Hellwig <hch@lst.de> wrote:
>
> Move copying the siginfo to userspace into the callers, so that the
> compat_siginfo conversion can be reused by the ELF coredump code without
> set_fs magic.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks all good to me, but I noticed that the naming is now a bit
inconsistent. to_compat_siginfo() is basically the reverse of
post_copy_siginfo_from_user32(), but the names are very different.

I suppose this can always be cleaned up later though, as your
naming choice is more consistent with how things are in the
rest of the kernel these days.

    Arnd
diff mbox series

Patch

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index 2bf188942d5c..0fbaed2562bc 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -301,6 +301,7 @@  int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
 			compat_sigset_t *set, struct pt_regs *regs)
 {
 	struct rt_sigframe_ia32 __user *frame;
+	struct compat_siginfo new;
 	void __user *restorer;
 	void __user *fp = NULL;
 
@@ -350,7 +351,8 @@  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, SA_IA32_ABI))
+	to_compat_siginfo(&new, &ksig->info, SA_IA32_ABI);
+	if (copy_to_user(&frame->info, &new, sizeof(frame->info)))
 		return -EFAULT;
 
 	/* Set up registers for signal handler */
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index bbd451631790..6ff1265f071b 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -517,6 +517,7 @@  static int x32_setup_rt_frame(struct ksignal *ksig,
 {
 #ifdef CONFIG_X86_X32_ABI
 	struct rt_sigframe_x32 __user *frame;
+	struct compat_siginfo new;
 	unsigned long uc_flags;
 	void __user *restorer;
 	void __user *fp = NULL;
@@ -543,8 +544,8 @@  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,
-				SA_X32_ABI))
+		to_compat_siginfo(&new, &ksig->info, SA_X32_ABI);
+		if (copy_to_user(&frame->info, &new, sizeof(frame->info)))
 			return -EFAULT;
 	}
 
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 14eec6116110..218ebba1e454 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -404,8 +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);
+void to_compat_siginfo(struct compat_siginfo *to,
+		const struct kernel_siginfo *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 092fee008242..0f3e7fded3a5 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3235,88 +3235,82 @@  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,
+void to_compat_siginfo(struct compat_siginfo *to,
 		const struct kernel_siginfo *from, unsigned int flags)
 {
-	struct compat_siginfo new;
-	memset(&new, 0, sizeof(new));
+	memset(to, 0, sizeof(*to));
+	to->si_signo = from->si_signo;
+	to->si_errno = from->si_errno;
+	to->si_code  = from->si_code;
 
-	new.si_signo = from->si_signo;
-	new.si_errno = from->si_errno;
-	new.si_code  = from->si_code;
-	switch(siginfo_layout(from->si_signo, from->si_code)) {
+	switch (siginfo_layout(from->si_signo, from->si_code)) {
 	case SIL_KILL:
-		new.si_pid = from->si_pid;
-		new.si_uid = from->si_uid;
+		to->si_pid = from->si_pid;
+		to->si_uid = from->si_uid;
 		break;
 	case SIL_TIMER:
-		new.si_tid     = from->si_tid;
-		new.si_overrun = from->si_overrun;
-		new.si_int     = from->si_int;
+		to->si_tid     = from->si_tid;
+		to->si_overrun = from->si_overrun;
+		to->si_int     = from->si_int;
 		break;
 	case SIL_POLL:
-		new.si_band = from->si_band;
-		new.si_fd   = from->si_fd;
+		to->si_band = from->si_band;
+		to->si_fd   = from->si_fd;
 		break;
 	case SIL_FAULT:
-		new.si_addr = ptr_to_compat(from->si_addr);
+		to->si_addr = ptr_to_compat(from->si_addr);
 #ifdef __ARCH_SI_TRAPNO
-		new.si_trapno = from->si_trapno;
+		to->si_trapno = from->si_trapno;
 #endif
 		break;
 	case SIL_FAULT_MCEERR:
-		new.si_addr = ptr_to_compat(from->si_addr);
+		to->si_addr = ptr_to_compat(from->si_addr);
 #ifdef __ARCH_SI_TRAPNO
-		new.si_trapno = from->si_trapno;
+		to->si_trapno = from->si_trapno;
 #endif
-		new.si_addr_lsb = from->si_addr_lsb;
+		to->si_addr_lsb = from->si_addr_lsb;
 		break;
 	case SIL_FAULT_BNDERR:
-		new.si_addr = ptr_to_compat(from->si_addr);
+		to->si_addr = ptr_to_compat(from->si_addr);
 #ifdef __ARCH_SI_TRAPNO
-		new.si_trapno = from->si_trapno;
+		to->si_trapno = from->si_trapno;
 #endif
-		new.si_lower = ptr_to_compat(from->si_lower);
-		new.si_upper = ptr_to_compat(from->si_upper);
+		to->si_lower = ptr_to_compat(from->si_lower);
+		to->si_upper = ptr_to_compat(from->si_upper);
 		break;
 	case SIL_FAULT_PKUERR:
-		new.si_addr = ptr_to_compat(from->si_addr);
+		to->si_addr = ptr_to_compat(from->si_addr);
 #ifdef __ARCH_SI_TRAPNO
-		new.si_trapno = from->si_trapno;
+		to->si_trapno = from->si_trapno;
 #endif
-		new.si_pkey = from->si_pkey;
+		to->si_pkey = from->si_pkey;
 		break;
 	case SIL_CHLD:
-		new.si_pid    = from->si_pid;
-		new.si_uid    = from->si_uid;
-		new.si_status = from->si_status;
+		to->si_pid    = from->si_pid;
+		to->si_uid    = from->si_uid;
+		to->si_status = from->si_status;
 #ifdef CONFIG_X86_X32_ABI
 		if (flags & SA_X32_ABI) {
-			new._sifields._sigchld_x32._utime = from->si_utime;
-			new._sifields._sigchld_x32._stime = from->si_stime;
+			to->_sifields._sigchld_x32._utime = from->si_utime;
+			to->_sifields._sigchld_x32._stime = from->si_stime;
 		} else
 #endif
 		{
-			new.si_utime = from->si_utime;
-			new.si_stime = from->si_stime;
+			to->si_utime = from->si_utime;
+			to->si_stime = from->si_stime;
 		}
 		break;
 	case SIL_RT:
-		new.si_pid = from->si_pid;
-		new.si_uid = from->si_uid;
-		new.si_int = from->si_int;
+		to->si_pid = from->si_pid;
+		to->si_uid = from->si_uid;
+		to->si_int = from->si_int;
 		break;
 	case SIL_SYS:
-		new.si_call_addr = ptr_to_compat(from->si_call_addr);
-		new.si_syscall   = from->si_syscall;
-		new.si_arch      = from->si_arch;
+		to->si_call_addr = ptr_to_compat(from->si_call_addr);
+		to->si_syscall   = from->si_syscall;
+		to->si_arch      = from->si_arch;
 		break;
 	}
-
-	if (copy_to_user(to, &new, sizeof(struct compat_siginfo)))
-		return -EFAULT;
-
-	return 0;
 }
 
 #ifndef compat_siginfo_flags
@@ -3326,7 +3320,12 @@  int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
 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());
+	struct compat_siginfo new;
+
+	to_compat_siginfo(&new, from, compat_siginfo_flags());
+	if (copy_to_user(to, &new, sizeof(*to)))
+		return -EFAULT;
+	return 0;
 }
 
 static int post_copy_siginfo_from_user32(kernel_siginfo_t *to,