linux-kernel - [PATCH v2 19/40] ia64: fix put

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: <1420558883-10131-20-git-send-email-mst@redhat.com>
Date:	Tue, 6 Jan 2015 17:44:34 +0200
From:	"Michael S. Tsirkin" <mst@...hat.com>
To:	linux-kernel@...r.kernel.org
Cc:	Arnd Bergmann <arnd@...db.de>, linux-arch@...r.kernel.org,
	Tony Luck <tony.luck@...el.com>,
	Fenghua Yu <fenghua.yu@...el.com>,
	Thierry Reding <treding@...dia.com>, linux-ia64@...r.kernel.org
Subject: [PATCH v2 19/40] ia64: fix put_user sparse errors

virtio wants to write bitwise types to userspace using put_user.
At the moment this triggers sparse errors, since the value is passed
through an integer.

For example:

	__le32 __user *p;
	__le32 x;
	put_user(x, p);

is safe, but currently triggers a sparse warning.

Fix that up using __force.

Note: this does not suppress any useful sparse checks since callers
do a cast (__typeof__(*(ptr))) (x) which in turn forces all the
necessary type checks.

Signed-off-by: Michael S. Tsirkin <mst@...hat.com>
---
 arch/ia64/include/asm/uaccess.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 967c312..4f3fb6cc 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -169,10 +169,11 @@ do {									\
 	(err) = ia64_getreg(_IA64_REG_R8);				\
 	(val) = ia64_getreg(_IA64_REG_R9);				\
 } while (0)
-# define __put_user_size(val, addr, n, err)							\
-do {												\
-	__st_user("__ex_table", (unsigned long) addr, n, RELOC_TYPE, (unsigned long) (val));	\
-	(err) = ia64_getreg(_IA64_REG_R8);							\
+# define __put_user_size(val, addr, n, err)				\
+do {									\
+	__st_user("__ex_table", (unsigned long) addr, n, RELOC_TYPE,	\
+		  (__force unsigned long) (val));			\
+	(err) = ia64_getreg(_IA64_REG_R8);				\
 } while (0)
 #endif /* !ASM_SUPPORTED */
 
-- 
MST

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/