https://github.com/torvalds/linux
Revision 7e76f34fa103677a27d96a7cfef8ce61389a32de authored by Aruna Balakrishnaiah on 08 August 2013, 17:03:49 UTC, committed by Benjamin Herrenschmidt on 09 August 2013, 08:06:40 UTC
When reading from pstore there is a buffer overflow during decompression
due to the header added in unzip_oops. Remove unzip_oops and call
pstore_decompress directly in nvram_pstore_read. Allocate buffer of size
report_length of the oops header as header will not be deallocated in pstore.
Since we have 'openssl' command line tool to decompress the compressed data,
dump the compressed data in case decompression fails instead of not dumping
anything.

Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
1 parent 4e90a2a
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Tip revision: 7e76f34fa103677a27d96a7cfef8ce61389a32de authored by Aruna Balakrishnaiah on 08 August 2013, 17:03:49 UTC
powerpc/pseries: Fix buffer overflow when reading from pstore
Tip revision: 7e76f34
proc.c
/*
 * Scatterlist Cryptographic API.
 *
 * Procfs information.
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option) 
 * any later version.
 *
 */

#include <linux/atomic.h>
#include <linux/init.h>
#include <linux/crypto.h>
#include <linux/module.h>	/* for module_name() */
#include <linux/rwsem.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/sysctl.h>
#include "internal.h"

#ifdef CONFIG_CRYPTO_FIPS
static struct ctl_table crypto_sysctl_table[] = {
	{
		.procname       = "fips_enabled",
		.data           = &fips_enabled,
		.maxlen         = sizeof(int),
		.mode           = 0444,
		.proc_handler   = proc_dointvec
	},
	{}
};

static struct ctl_table crypto_dir_table[] = {
	{
		.procname       = "crypto",
		.mode           = 0555,
		.child          = crypto_sysctl_table
	},
	{}
};

static struct ctl_table_header *crypto_sysctls;

static void crypto_proc_fips_init(void)
{
	crypto_sysctls = register_sysctl_table(crypto_dir_table);
}

static void crypto_proc_fips_exit(void)
{
	if (crypto_sysctls)
		unregister_sysctl_table(crypto_sysctls);
}
#else
#define crypto_proc_fips_init()
#define crypto_proc_fips_exit()
#endif

static void *c_start(struct seq_file *m, loff_t *pos)
{
	down_read(&crypto_alg_sem);
	return seq_list_start(&crypto_alg_list, *pos);
}

static void *c_next(struct seq_file *m, void *p, loff_t *pos)
{
	return seq_list_next(p, &crypto_alg_list, pos);
}

static void c_stop(struct seq_file *m, void *p)
{
	up_read(&crypto_alg_sem);
}

static int c_show(struct seq_file *m, void *p)
{
	struct crypto_alg *alg = list_entry(p, struct crypto_alg, cra_list);
	
	seq_printf(m, "name         : %s\n", alg->cra_name);
	seq_printf(m, "driver       : %s\n", alg->cra_driver_name);
	seq_printf(m, "module       : %s\n", module_name(alg->cra_module));
	seq_printf(m, "priority     : %d\n", alg->cra_priority);
	seq_printf(m, "refcnt       : %d\n", atomic_read(&alg->cra_refcnt));
	seq_printf(m, "selftest     : %s\n",
		   (alg->cra_flags & CRYPTO_ALG_TESTED) ?
		   "passed" : "unknown");

	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
		seq_printf(m, "type         : larval\n");
		seq_printf(m, "flags        : 0x%x\n", alg->cra_flags);
		goto out;
	}

	if (alg->cra_type && alg->cra_type->show) {
		alg->cra_type->show(m, alg);
		goto out;
	}
	
	switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_LARVAL)) {
	case CRYPTO_ALG_TYPE_CIPHER:
		seq_printf(m, "type         : cipher\n");
		seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
		seq_printf(m, "min keysize  : %u\n",
					alg->cra_cipher.cia_min_keysize);
		seq_printf(m, "max keysize  : %u\n",
					alg->cra_cipher.cia_max_keysize);
		break;
	case CRYPTO_ALG_TYPE_COMPRESS:
		seq_printf(m, "type         : compression\n");
		break;
	default:
		seq_printf(m, "type         : unknown\n");
		break;
	}

out:
	seq_putc(m, '\n');
	return 0;
}

static const struct seq_operations crypto_seq_ops = {
	.start		= c_start,
	.next		= c_next,
	.stop		= c_stop,
	.show		= c_show
};

static int crypto_info_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &crypto_seq_ops);
}
        
static const struct file_operations proc_crypto_ops = {
	.open		= crypto_info_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release
};

void __init crypto_init_proc(void)
{
	proc_create("crypto", 0, NULL, &proc_crypto_ops);
	crypto_proc_fips_init();
}

void __exit crypto_exit_proc(void)
{
	crypto_proc_fips_exit();
	remove_proc_entry("crypto", NULL);
}
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