/* * quota.c - NTFS kernel quota ($Quota) handling. Part of the Linux-NTFS * project. * * Copyright (c) 2004 Anton Altaparmakov * * This program/include file 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. * * This program/include file is distributed in the hope that it will be * useful, but WITHOUT ANY WARRANTY; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program (in the main directory of the Linux-NTFS * distribution in the file COPYING); if not, write to the Free Software * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifdef NTFS_RW #include "index.h" #include "quota.h" #include "debug.h" #include "ntfs.h" /** * ntfs_mark_quotas_out_of_date - mark the quotas out of date on an ntfs volume * @vol: ntfs volume on which to mark the quotas out of date * * Mark the quotas out of date on the ntfs volume @vol and return 'true' on * success and 'false' on error. */ bool ntfs_mark_quotas_out_of_date(ntfs_volume *vol) { ntfs_index_context *ictx; QUOTA_CONTROL_ENTRY *qce; const le32 qid = QUOTA_DEFAULTS_ID; int err; ntfs_debug("Entering."); if (NVolQuotaOutOfDate(vol)) goto done; if (!vol->quota_ino || !vol->quota_q_ino) { ntfs_error(vol->sb, "Quota inodes are not open."); return false; } inode_lock(vol->quota_q_ino); ictx = ntfs_index_ctx_get(NTFS_I(vol->quota_q_ino)); if (!ictx) { ntfs_error(vol->sb, "Failed to get index context."); goto err_out; } err = ntfs_index_lookup(&qid, sizeof(qid), ictx); if (err) { if (err == -ENOENT) ntfs_error(vol->sb, "Quota defaults entry is not " "present."); else ntfs_error(vol->sb, "Lookup of quota defaults entry " "failed."); goto err_out; } if (ictx->data_len < offsetof(QUOTA_CONTROL_ENTRY, sid)) { ntfs_error(vol->sb, "Quota defaults entry size is invalid. " "Run chkdsk."); goto err_out; } qce = (QUOTA_CONTROL_ENTRY*)ictx->data; if (le32_to_cpu(qce->version) != QUOTA_VERSION) { ntfs_error(vol->sb, "Quota defaults entry version 0x%x is not " "supported.", le32_to_cpu(qce->version)); goto err_out; } ntfs_debug("Quota defaults flags = 0x%x.", le32_to_cpu(qce->flags)); /* If quotas are already marked out of date, no need to do anything. */ if (qce->flags & QUOTA_FLAG_OUT_OF_DATE) goto set_done; /* * If quota tracking is neither requested, nor enabled and there are no * pending deletes, no need to mark the quotas out of date. */ if (!(qce->flags & (QUOTA_FLAG_TRACKING_ENABLED | QUOTA_FLAG_TRACKING_REQUESTED | QUOTA_FLAG_PENDING_DELETES))) goto set_done; /* * Set the QUOTA_FLAG_OUT_OF_DATE bit thus marking quotas out of date. * This is verified on WinXP to be sufficient to cause windows to * rescan the volume on boot and update all quota entries. */ qce->flags |= QUOTA_FLAG_OUT_OF_DATE; /* Ensure the modified flags are written to disk. */ ntfs_index_entry_flush_dcache_page(ictx); ntfs_index_entry_mark_dirty(ictx); set_done: ntfs_index_ctx_put(ictx); inode_unlock(vol->quota_q_ino); /* * We set the flag so we do not try to mark the quotas out of date * again on remount. */ NVolSetQuotaOutOfDate(vol); done: ntfs_debug("Done."); return true; err_out: if (ictx) ntfs_index_ctx_put(ictx); inode_unlock(vol->quota_q_ino); return false; } #endif /* NTFS_RW */ n value='2'>2space:mode:
authorDouglas Miller <dougmill@linux.vnet.ibm.com>2017-01-28 06:42:20 -0600
committerTejun Heo <tj@kernel.org>2017-01-28 07:49:42 -0500
commit966d2b04e070bc040319aaebfec09e0144dc3341 (patch)
tree4b96156e3d1dd4dfd6039b7c219c9dc4616da52d /fs/nfs/blocklayout/extent_tree.c
parent1b1bc42c1692e9b62756323c675a44cb1a1f9dbd (diff)
percpu-refcount: fix reference leak during percpu-atomic transition
percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'fs/nfs/blocklayout/extent_tree.c')