[MIPS] Fix sigset_t endianess swapping issues in 32-bit compat code.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 55 insertions, 0 deletions

diff --git a/include/asm-mips/compat-signal.h b/include/asm-mips/compat-signal.h
new file mode 100644
index 000000000000..672077084aa1
--- /dev/null
+++ b/include/asm-mips/compat-signal.h
@@ -0,0 +1,55 @@
+#ifndef __ASM_COMPAT_SIGNAL_H
+#define __ASM_COMPAT_SIGNAL_H
+
+#include <linux/bug.h>
+#include <linux/compat.h>
+#include <linux/compiler.h>
+
+static inline int __copy_conv_sigset_to_user(compat_sigset_t __user *d,
+	const sigset_t *s)
+{
+	int err;
+
+	BUG_ON(sizeof(*d) != sizeof(*s));
+	BUG_ON(_NSIG_WORDS != 2);
+
+	err  = __put_user(s->sig[0],       &d->sig[0]);
+	err |= __put_user(s->sig[0] >> 32, &d->sig[1]);
+	err |= __put_user(s->sig[1],       &d->sig[2]);
+	err |= __put_user(s->sig[1] >> 32, &d->sig[3]);
+
+	return err;
+}
+
+static inline int __copy_conv_sigset_from_user(sigset_t *d,
+	const compat_sigset_t __user *s)
+{
+	int err;
+	union sigset_u {
+		sigset_t	s;
+		compat_sigset_t c;
+	} *u = (union sigset_u *) d;
+
+	BUG_ON(sizeof(*d) != sizeof(*s));
+	BUG_ON(_NSIG_WORDS != 2);
+
+	if (unlikely(!access_ok(VERIFY_READ, d, sizeof(*d))))
+		return -EFAULT;
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	err  = __get_user(u->c.sig[1], &s->sig[0]);
+	err |= __get_user(u->c.sig[0], &s->sig[1]);
+	err |= __get_user(u->c.sig[3], &s->sig[2]);
+	err |= __get_user(u->c.sig[2], &s->sig[3]);
+#endif
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+	err  = __get_user(u->c.sig[0], &s->sig[0]);
+	err |= __get_user(u->c.sig[1], &s->sig[1]);
+	err |= __get_user(u->c.sig[2], &s->sig[2]);
+	err |= __get_user(u->c.sig[3], &s->sig[3]);
+#endif
+
+	return err;
+}
+
+#endif /* __ASM_COMPAT_SIGNAL_H */