linux-kernel - [PATCH] module: do not print allocation-fail warning on bogus user buffer size

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]

Date:	Mon, 16 Feb 2015 13:23:03 +0200
From:	"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
To:	Rusty Russell <rusty@...tcorp.com.au>
Cc:	linux-kernel@...r.kernel.org,
	"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
	Dave Jones <davej@...emonkey.org.uk>,
	Sasha Levin <sasha.levin@...cle.com>
Subject: [PATCH] module: do not print allocation-fail warning on bogus user buffer size

init_module(2) passes user-specified buffer length directly to
vmalloc(). It makes warn_alloc_failed() to print out a lot of info into
dmesg if user specified insane size, like -1.

Let's silence the warning. It doesn't add much value to -ENOMEM return
code. Without the patch the syscall is prohibitive noisy for testing
with trinity.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>
Cc: Dave Jones <davej@...emonkey.org.uk>
Cc: Sasha Levin <sasha.levin@...cle.com>
---
 kernel/module.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/module.c b/kernel/module.c
index b34813f725e9..f63e5e8f3385 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2494,7 +2494,8 @@ static int copy_module_from_user(const void __user *umod, unsigned long len,
 		return err;
 
 	/* Suck in entire file: we'll want most of it. */
-	info->hdr = vmalloc(info->len);
+	info->hdr = __vmalloc(info->len,
+			GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
 	if (!info->hdr)
 		return -ENOMEM;
 
-- 
2.1.4

--
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/