linux-kernel - [PATCH 1/2] module: fix BUG_ON() for powerpc (and other function descriptor archs)

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: <200908262202.54457.rusty@rustcorp.com.au>
Date:	Wed, 26 Aug 2009 22:02:54 +0930
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	linux-kernel@...r.kernel.org, Paul Mackerras <paulus@...ba.org>
Subject: [PATCH 1/2] module: fix BUG_ON() for powerpc (and other function descriptor archs)

The rarely-used symbol_put_addr() needs to use dereference_function_descriptor
on powerpc.

Reported-by: Paul Mackerras <paulus@...ba.org>
Signed-off-by: Rusty Russell <rusty@...tcorp.com.au.

diff --git a/kernel/module.c b/kernel/module.c
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -909,16 +909,18 @@ void __symbol_put(const char *symbol)
 }
 EXPORT_SYMBOL(__symbol_put);
 
+/* Note this assumes addr is a function, which it currently always is. */
 void symbol_put_addr(void *addr)
 {
 	struct module *modaddr;
+	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
 
-	if (core_kernel_text((unsigned long)addr))
+	if (core_kernel_text(a))
 		return;
 
 	/* module_text_address is safe here: we're supposed to have reference
 	 * to module from symbol_get, so it can't go away. */
-	modaddr = __module_text_address((unsigned long)addr);
+	modaddr = __module_text_address(a);
 	BUG_ON(!modaddr);
 	module_put(modaddr);
 }
--
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/