Re: Two vulnerabilities are founded,please confirm.

[Samuel Tardieu <sam@rfc1149.net>]

>>>>> "ADLab" == ADLab  <adlab@venustech.com.cn> writes:

ADLab> Advisory: [AD_LAB-06011] Linux kernel Filesystem Mount Dead
ADLab> Loop Class: Design Error

Would a simple fix like this one (untested) work?

Check that the requested block fits in the device.

Fix for advisory AD_LAB-06011 Linux kernel Filesystem Mount Dead Loop.

Signed-off-by: Samuel Tardieu <sam@rfc1149.net>

diff -r db51efd75e66 fs/buffer.c
--- a/fs/buffer.c	Sun Sep 10 01:02:33 2006 +0200
+++ b/fs/buffer.c	Tue Sep 12 17:54:13 2006 +0200
@@ -1456,7 +1456,17 @@ struct buffer_head *
 struct buffer_head *
 __getblk(struct block_device *bdev, sector_t block, int size)
 {
-	struct buffer_head *bh = __find_get_block(bdev, block, size);
+	struct buffer_head *bh;
+	char b[BDEVNAME_SIZE];
+
+	if (block >= bdev->bd_disk->capacity) {
+		printk(KERN_ERR "Invalid block number %Ld requested on device %s",
+		       (unsigned long long)block,
+		       bdevname(bdev, b));
+		return NULL;
+	}
+
+	bh = __find_get_block(bdev, block, size);
 
 	might_sleep();
 	if (bh == NULL)