Revision 1d02369dba2cd9db110f0f35d9a777ee691e498b authored by Linus Torvalds on 25 March 2016, 03:00:44 UTC, committed by Linus Torvalds on 25 March 2016, 03:00:44 UTC
Pull block fixes from Jens Axboe:
 "Final round of fixes for this merge window - some of this has come up
  after the initial pull request, and some of it was put in a post-merge
  branch before the merge window.

  This contains:

   - Fix for a bad check for an error on dma mapping in the mtip32xx
     driver, from Alexey Khoroshilov.

   - A set of fixes for lightnvm, from Javier, Matias, and Wenwei.

   - An NVMe completion record corruption fix from Marta, ensuring that
     we read things in the right order.

   - Two writeback fixes from Tejun, marked for stable@ as well.

   - A blk-mq sw queue iterator fix from Thomas, fixing an oops for
     sparse CPU maps.  They hit this in the hot plug/unplug rework"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: avoid cqe corruption when update at the same time as read
  writeback, cgroup: fix use of the wrong bdi_writeback which mismatches the inode
  writeback, cgroup: fix premature wb_put() in locked_inode_to_wb_and_lock_list()
  blk-mq: Use proper cpumask iterator
  mtip32xx: fix checks for dma mapping errors
  lightnvm: do not load L2P table if not supported
  lightnvm: do not reserve lun on l2p loading
  nvme: lightnvm: return ppa completion status
  lightnvm: add a bitmap of luns
  lightnvm: specify target's logical address area
  null_blk: add lightnvm null_blk device to the nullb_list
2 parent s 8f40842 + d783e0b
Raw File
min_addr.c
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/security.h>
#include <linux/sysctl.h>

/* amount of vm to protect from userspace access by both DAC and the LSM*/
unsigned long mmap_min_addr;
/* amount of vm to protect from userspace using CAP_SYS_RAWIO (DAC) */
unsigned long dac_mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
/* amount of vm to protect from userspace using the LSM = CONFIG_LSM_MMAP_MIN_ADDR */

/*
 * Update mmap_min_addr = max(dac_mmap_min_addr, CONFIG_LSM_MMAP_MIN_ADDR)
 */
static void update_mmap_min_addr(void)
{
#ifdef CONFIG_LSM_MMAP_MIN_ADDR
	if (dac_mmap_min_addr > CONFIG_LSM_MMAP_MIN_ADDR)
		mmap_min_addr = dac_mmap_min_addr;
	else
		mmap_min_addr = CONFIG_LSM_MMAP_MIN_ADDR;
#else
	mmap_min_addr = dac_mmap_min_addr;
#endif
}

/*
 * sysctl handler which just sets dac_mmap_min_addr = the new value and then
 * calls update_mmap_min_addr() so non MAP_FIXED hints get rounded properly
 */
int mmap_min_addr_handler(struct ctl_table *table, int write,
			  void __user *buffer, size_t *lenp, loff_t *ppos)
{
	int ret;

	if (write && !capable(CAP_SYS_RAWIO))
		return -EPERM;

	ret = proc_doulongvec_minmax(table, write, buffer, lenp, ppos);

	update_mmap_min_addr();

	return ret;
}

static int __init init_mmap_min_addr(void)
{
	update_mmap_min_addr();

	return 0;
}
pure_initcall(init_mmap_min_addr);
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