lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220216131332.1489939-5-arnd@kernel.org>
Date:   Wed, 16 Feb 2022 14:13:18 +0100
From:   Arnd Bergmann <arnd@...nel.org>
To:     Linus Torvalds <torvalds@...ux-foundation.org>,
        Christoph Hellwig <hch@....de>, linux-arch@...r.kernel.org,
        linux-mm@...ck.org, linux-api@...r.kernel.org, arnd@...db.de,
        linux-kernel@...r.kernel.org, viro@...iv.linux.org.uk
Cc:     linux@...linux.org.uk, will@...nel.org, guoren@...nel.org,
        bcain@...eaurora.org, geert@...ux-m68k.org, monstr@...str.eu,
        tsbogend@...ha.franken.de, nickhu@...estech.com,
        green.hu@...il.com, dinguyen@...nel.org, shorne@...il.com,
        deller@....de, mpe@...erman.id.au, peterz@...radead.org,
        mingo@...hat.com, mark.rutland@....com, hca@...ux.ibm.com,
        dalias@...c.org, davem@...emloft.net, richard@....at,
        x86@...nel.org, jcmvbkbc@...il.com, ebiederm@...ssion.com,
        akpm@...ux-foundation.org, ardb@...nel.org,
        linux-alpha@...r.kernel.org, linux-snps-arc@...ts.infradead.org,
        linux-csky@...r.kernel.org, linux-hexagon@...r.kernel.org,
        linux-ia64@...r.kernel.org, linux-m68k@...ts.linux-m68k.org,
        linux-mips@...r.kernel.org, openrisc@...ts.librecores.org,
        linux-parisc@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        linux-riscv@...ts.infradead.org, linux-s390@...r.kernel.org,
        linux-sh@...r.kernel.org, sparclinux@...r.kernel.org,
        linux-um@...ts.infradead.org, linux-xtensa@...ux-xtensa.org
Subject: [PATCH v2 04/18] sparc64: add __{get,put}_kernel_nocheck()

From: Arnd Bergmann <arnd@...db.de>

sparc64 is one of the architectures that uses separate address
spaces for kernel and user addresses, so __get_kernel_nofault()
can not just call into the normal __get_user() without the
access_ok() check.

Instead duplicate __get_user() and __put_user() into their
in-kernel versions, with minor changes for the calling conventions
and leaving out the address space modifier on the assembler
instruction.

This could surely be written more elegantly, but duplicating it
gets the job done.

Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
 arch/sparc/include/asm/uaccess_64.h | 78 +++++++++++++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h
index 30eb4c6414d1..b283798315b1 100644
--- a/arch/sparc/include/asm/uaccess_64.h
+++ b/arch/sparc/include/asm/uaccess_64.h
@@ -100,6 +100,42 @@ void __retl_efault(void);
 struct __large_struct { unsigned long buf[100]; };
 #define __m(x) ((struct __large_struct *)(x))
 
+#define __put_kernel_nofault(dst, src, type, label)			\
+do {									\
+	type *addr = (type __force *)(dst);				\
+	type data = *(type *)src;					\
+	register int __pu_ret;						\
+	switch (sizeof(type)) {						\
+	case 1: __put_kernel_asm(data, b, addr, __pu_ret); break;	\
+	case 2: __put_kernel_asm(data, h, addr, __pu_ret); break;	\
+	case 4: __put_kernel_asm(data, w, addr, __pu_ret); break;	\
+	case 8: __put_kernel_asm(data, x, addr, __pu_ret); break;	\
+	default: __pu_ret = __put_user_bad(); break;			\
+	}								\
+	if (__pu_ret)							\
+		goto label;						\
+} while (0)
+
+#define __put_kernel_asm(x, size, addr, ret)				\
+__asm__ __volatile__(							\
+		"/* Put kernel asm, inline. */\n"			\
+	"1:\t"	"st"#size " %1, [%2]\n\t"				\
+		"clr	%0\n"						\
+	"2:\n\n\t"							\
+		".section .fixup,#alloc,#execinstr\n\t"			\
+		".align	4\n"						\
+	"3:\n\t"							\
+		"sethi	%%hi(2b), %0\n\t"				\
+		"jmpl	%0 + %%lo(2b), %%g0\n\t"			\
+		" mov	%3, %0\n\n\t"					\
+		".previous\n\t"						\
+		".section __ex_table,\"a\"\n\t"				\
+		".align	4\n\t"						\
+		".word	1b, 3b\n\t"					\
+		".previous\n\n\t"					\
+	       : "=r" (ret) : "r" (x), "r" (__m(addr)),			\
+		 "i" (-EFAULT))
+
 #define __put_user_nocheck(data, addr, size) ({			\
 	register int __pu_ret;					\
 	switch (size) {						\
@@ -134,6 +170,48 @@ __asm__ __volatile__(							\
 
 int __put_user_bad(void);
 
+#define __get_kernel_nofault(dst, src, type, label)			     \
+do {									     \
+	type *addr = (type __force *)(src);		     		     \
+	register int __gu_ret;						     \
+	register unsigned long __gu_val;				     \
+	switch (sizeof(type)) {						     \
+		case 1: __get_kernel_asm(__gu_val, ub, addr, __gu_ret); break; \
+		case 2: __get_kernel_asm(__gu_val, uh, addr, __gu_ret); break; \
+		case 4: __get_kernel_asm(__gu_val, uw, addr, __gu_ret); break; \
+		case 8: __get_kernel_asm(__gu_val, x, addr, __gu_ret); break;  \
+		default:						     \
+			__gu_val = 0;					     \
+			__gu_ret = __get_user_bad();			     \
+			break;						     \
+	} 								     \
+	if (__gu_ret)							     \
+		goto label;						     \
+	*(type *)dst = (__force type) __gu_val;				     \
+} while (0)
+#define __get_kernel_asm(x, size, addr, ret)				\
+__asm__ __volatile__(							\
+		"/* Get kernel asm, inline. */\n"			\
+	"1:\t"	"ld"#size " [%2], %1\n\t"				\
+		"clr	%0\n"						\
+	"2:\n\n\t"							\
+		".section .fixup,#alloc,#execinstr\n\t"			\
+		".align	4\n"						\
+	"3:\n\t"							\
+		"sethi	%%hi(2b), %0\n\t"				\
+		"clr	%1\n\t"						\
+		"jmpl	%0 + %%lo(2b), %%g0\n\t"			\
+		" mov	%3, %0\n\n\t"					\
+		".previous\n\t"						\
+		".section __ex_table,\"a\"\n\t"				\
+		".align	4\n\t"						\
+		".word	1b, 3b\n\n\t"					\
+		".previous\n\t"						\
+	       : "=r" (ret), "=r" (x) : "r" (__m(addr)),		\
+		 "i" (-EFAULT))
+
+#define HAVE_GET_KERNEL_NOFAULT
+
 #define __get_user_nocheck(data, addr, size, type) ({			     \
 	register int __gu_ret;						     \
 	register unsigned long __gu_val;				     \
-- 
2.29.2

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ