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Revision be14eb619108fa8b7120eb2c42d66d5f623ae10e authored by Brian King on 10 September 2010, 07:03:21 UTC, committed by Jens Axboe on 10 September 2010, 07:03:21 UTC 
block: Range check cpu in blk_cpu_to_group
 
While testing CPU DLPAR, the following problem was discovered.
We were DLPAR removing the first CPU, which in this case was
logical CPUs 0-3. CPUs 0-2 were already marked offline and
we were in the process of offlining CPU 3. After marking
the CPU inactive and offline in cpu_disable, but before the
cpu was completely idle (cpu_die), we ended up in __make_request
on CPU 3. There we looked at the topology map to see which CPU
to complete the I/O on and found no CPUs in the cpu_sibling_map.
This resulted in the block layer setting the completion cpu
to be NR_CPUS, which then caused an oops when we tried to
complete the I/O.

Fix this by sanity checking the value we return from blk_cpu_to_group
to be a valid cpu value.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
1 parent edce682
Raw File
xattr_trusted.c 
/*
 * linux/fs/ext2/xattr_trusted.c
 * Handler for trusted extended attributes.
 *
 * Copyright (C) 2003 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
 */

#include <linux/module.h>
#include <linux/string.h>
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/ext2_fs.h>
#include "xattr.h"

static size_t
ext2_xattr_trusted_list(struct dentry *dentry, char *list, size_t list_size,
		const char *name, size_t name_len, int type)
{
	const int prefix_len = XATTR_TRUSTED_PREFIX_LEN;
	const size_t total_len = prefix_len + name_len + 1;

	if (!capable(CAP_SYS_ADMIN))
		return 0;

	if (list && total_len <= list_size) {
		memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
		memcpy(list+prefix_len, name, name_len);
		list[prefix_len + name_len] = '\0';
	}
	return total_len;
}

static int
ext2_xattr_trusted_get(struct dentry *dentry, const char *name,
		void *buffer, size_t size, int type)
{
	if (strcmp(name, "") == 0)
		return -EINVAL;
	return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_TRUSTED, name,
			      buffer, size);
}

static int
ext2_xattr_trusted_set(struct dentry *dentry, const char *name,
		const void *value, size_t size, int flags, int type)
{
	if (strcmp(name, "") == 0)
		return -EINVAL;
	return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_TRUSTED, name,
			      value, size, flags);
}

const struct xattr_handler ext2_xattr_trusted_handler = {
	.prefix	= XATTR_TRUSTED_PREFIX,
	.list	= ext2_xattr_trusted_list,
	.get	= ext2_xattr_trusted_get,
	.set	= ext2_xattr_trusted_set,
};
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