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Date: Mon, 28 Jul 2003 00:22:16 -0700
From: Andrew Morton <akpm@osdl.org>
To: "Andrey Borzenkov" <arvidjaar@mail.ru>
Cc: linux-kernel@vger.kernel.org, webvenza@libero.it
Subject: Re: 2.6.0-test1 devfs question
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"Andrey Borzenkov" <arvidjaar@mail.ru> wrote:
>
> the bug is almost for sure in init/do_mount_devfs.c:read_dir; it
>  allocates static buffer of size at most 2**MAX_ORDER and tries to
>  read the whole dir at once.

Yes, that function is buggy.

diff -puN init/do_mounts_devfs.c~read_dir-fix init/do_mounts_devfs.c
--- 25/init/do_mounts_devfs.c~read_dir-fix	2003-07-28 00:21:40.000000000 -0700
+++ 25-akpm/init/do_mounts_devfs.c	2003-07-28 00:21:40.000000000 -0700
@@ -54,7 +54,7 @@ static void * __init read_dir(char *path
 	if (fd < 0)
 		return NULL;
 
-	for (size = 1 << 9; size <= (1 << MAX_ORDER); size <<= 1) {
+	for (size = 1 << 9; size <= (PAGE_SIZE << MAX_ORDER); size <<= 1) {
 		void *p = kmalloc(size, GFP_KERNEL);
 		int n;
 		if (!p)

_