linux-kernel - [PATCH] powerpc/uaccess: fix warning/error with access

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-next>] [day] [month] [year] [list]

Message-Id: <40873f45f922b28c727c013e3883be467fc31c56.1539852411.git.christophe.leroy@c-s.fr>
Date:   Thu, 18 Oct 2018 08:48:42 +0000 (UTC)
From:   Christophe Leroy <christophe.leroy@....fr>
To:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>
Cc:     linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH] powerpc/uaccess: fix warning/error with access_ok()

With the following peace of code, the following compilation warning
is encountered:

	if (_IOC_DIR(ioc) != _IOC_NONE) {
		int verify = _IOC_DIR(ioc) & _IOC_READ ? VERIFY_WRITE : VERIFY_READ;

		if (!access_ok(verify, ioarg, _IOC_SIZE(ioc))) {

drivers/platform/test/dev.c: In function ‘my_ioctl’:
drivers/platform/test/dev.c:219:7: warning: unused variable ‘verify’ [-Wunused-variable]
   int verify = _IOC_DIR(ioc) & _IOC_READ ? VERIFY_WRITE : VERIFY_READ;

This patch fixes it by handing the type to __access_ok(), changing it
to an inline function for PPC64 as already done for PPC32

Signed-off-by: Christophe Leroy <christophe.leroy@....fr>
---
 arch/powerpc/include/asm/uaccess.h | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 15bea9a0f260..97faf0353919 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -47,13 +47,16 @@ static inline void set_fs(mm_segment_t fs)
  * This check is sufficient because there is a large enough
  * gap between user addresses and the kernel addresses
  */
-#define __access_ok(addr, size, segment)	\
-	(((addr) <= (segment).seg) && ((size) <= (segment).seg))
+static inline int __access_ok(int type, unsigned long addr, unsigned long size,
+			      mm_segment_t seg)
+{
+	return addr <= seg.seg && size <= seg.seg;
+}
 
 #else
 
-static inline int __access_ok(unsigned long addr, unsigned long size,
-			mm_segment_t seg)
+static inline int __access_ok(int type, unsigned long addr, unsigned long size,
+			      mm_segment_t seg)
 {
 	if (addr > seg.seg)
 		return 0;
@@ -64,7 +67,7 @@ static inline int __access_ok(unsigned long addr, unsigned long size,
 
 #define access_ok(type, addr, size)		\
 	(__chk_user_ptr(addr),			\
-	 __access_ok((__force unsigned long)(addr), (size), get_fs()))
+	 __access_ok((type), (__force unsigned long)(addr), (size), get_fs()))
 
 /*
  * These are the main single-value transfer routines.  They automatically
-- 
2.13.3