- Dec 18, 2018
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Javier Barrio authored
Commit 1fa5efe3 (ext4: Use generic helpers for quotaon and quotaoff) made possible to call quotactl(Q_XQUOTAON/OFF) on ext4 filesystems with sysfile quota support. This leads to calling dquot_enable/disable without s_umount held in excl. mode, because quotactl_cmd_onoff checks only for Q_QUOTAON/OFF. The following WARN_ON_ONCE triggers (in this case for dquot_enable, ext4, latest Linus' tree): [ 117.807056] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: quota,prjquota [...] [ 155.036847] WARNING: CPU: 0 PID: 2343 at fs/quota/dquot.c:2469 dquot_enable+0x34/0xb9 [ 155.036851] Modules linked in: quota_v2 quota_tree ipv6 af_packet joydev mousedev psmouse serio_raw pcspkr i2c_piix4 intel_agp intel_gtt e1000 ttm drm_kms_helper drm agpgart fb_sys_fops syscopyarea sysfillrect sysimgblt i2c_core input_leds kvm_intel kvm irqbypass qemu_fw_cfg floppy evdev parport_pc parport button crc32c_generic dm_mod ata_generic pata_acpi ata_piix libata loop ext4 crc16 mbcache jbd2 usb_storage usbcore sd_mod scsi_mod [ 155.036901] CPU: 0 PID: 2343 Comm: qctl Not tainted 4.20.0-rc6-00025-gf5d582777bcb #9 [ 155.036903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 155.036911] RIP: 0010:dquot_enable+0x34/0xb9 [ 155.036915] Code: 41 56 41 55 41 54 55 53 4c 8b 6f 28 74 02 0f 0b 4d 8d 7d 70 49 89 fc 89 cb 41 89 d6 89 f5 4c 89 ff e8 23 09 ea ff 85 c0 74 0a <0f> 0b 4c 89 ff e8 8b 09 ea ff 85 db 74 6a 41 8b b5 f8 00 00 00 0f [ 155.036918] RSP: 0018:ffffb09b00493e08 EFLAGS: 00010202 [ 155.036922] RAX: 0000000000000001 RBX: 0000000000000008 RCX: 0000000000000008 [ 155.036924] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9781b67cd870 [ 155.036926] RBP: 0000000000000002 R08: 0000000000000000 R09: 61c8864680b583eb [ 155.036929] R10: ffffb09b00493e48 R11: ffffffffff7ce7d4 R12: ffff9781b7ee8d78 [ 155.036932] R13: ffff9781b67cd800 R14: 0000000000000004 R15: ffff9781b67cd870 [ 155.036936] FS: 00007fd813250b88(0000) GS:ffff9781ba000000(0000) knlGS:0000000000000000 [ 155.036939] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 155.036942] CR2: 00007fd812ff61d6 CR3: 000000007c882000 CR4: 00000000000006b0 [ 155.036951] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 155.036953] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 155.036955] Call Trace: [ 155.037004] dquot_quota_enable+0x8b/0xd0 [ 155.037011] kernel_quotactl+0x628/0x74e [ 155.037027] ? do_mprotect_pkey+0x2a6/0x2cd [ 155.037034] __x64_sys_quotactl+0x1a/0x1d [ 155.037041] do_syscall_64+0x55/0xe4 [ 155.037078] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 155.037105] RIP: 0033:0x7fd812fe1198 [ 155.037109] Code: 02 77 0d 48 89 c1 48 c1 e9 3f 75 04 48 8b 04 24 48 83 c4 50 5b c3 48 83 ec 08 49 89 ca 48 63 d2 48 63 ff b8 b3 00 00 00 0f 05 <48> 89 c7 e8 c1 eb ff ff 5a c3 48 63 ff b8 bb 00 00 00 0f 05 48 89 [ 155.037112] RSP: 002b:00007ffe8cd7b050 EFLAGS: 00000206 ORIG_RAX: 00000000000000b3 [ 155.037116] RAX: ffffffffffffffda RBX: 00007ffe8cd7b148 RCX: 00007fd812fe1198 [ 155.037119] RDX: 0000000000000000 RSI: 00007ffe8cd7cea9 RDI: 0000000000580102 [ 155.037121] RBP: 00007ffe8cd7b0f0 R08: 000055fc8eba8a9d R09: 0000000000000000 [ 155.037124] R10: 00007ffe8cd7b074 R11: 0000000000000206 R12: 00007ffe8cd7b168 [ 155.037126] R13: 000055fc8eba8897 R14: 0000000000000000 R15: 0000000000000000 [ 155.037131] ---[ end trace 210f864257175c51 ]--- and then the syscall proceeds without s_umount locking. This patch locks the superblock ->s_umount sem. in exclusive mode for all Q_XQUOTAON/OFF quotactls too in addition to Q_QUOTAON/OFF. AFAICT, other than ext4, only xfs and ocfs2 are affected by this change. The VFS will now call in xfs_quota_* functions with s_umount held, which wasn't the case before. This looks good to me but I can not say for sure. Ext4 and ocfs2 where already beeing called with s_umount exclusive via quota_quotaon/off which is basically the same. Signed-off-by:
Javier Barrio <javier.barrio.mart@gmail.com> Signed-off-by:
Jan Kara <jack@suse.cz>
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- Aug 22, 2018
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Jeremy Cline authored
'type' is user-controlled, so sanitize it after the bounds check to avoid using it in speculative execution. This covers the following potential gadgets detected with the help of smatch: * fs/ext4/super.c:5741 ext4_quota_read() warn: potential spectre issue 'sb_dqopt(sb)->files' [r] * fs/ext4/super.c:5778 ext4_quota_write() warn: potential spectre issue 'sb_dqopt(sb)->files' [r] * fs/f2fs/super.c:1552 f2fs_quota_read() warn: potential spectre issue 'sb_dqopt(sb)->files' [r] * fs/f2fs/super.c:1608 f2fs_quota_write() warn: potential spectre issue 'sb_dqopt(sb)->files' [r] * fs/quota/dquot.c:412 mark_info_dirty() warn: potential spectre issue 'sb_dqopt(sb)->info' [w] * fs/quota/dquot.c:933 dqinit_needed() warn: potential spectre issue 'dquots' [r] * fs/quota/dquot.c:2112 dquot_commit_info() warn: potential spectre issue 'dqopt->ops' [r] * fs/quota/dquot.c:2362 vfs_load_quota_inode() warn: potential spectre issue 'dqopt->files' [w] (local cap) * fs/quota/dquot.c:2369 vfs_load_quota_inode() warn: potential spectre issue 'dqopt->ops' [w] (local cap) * fs/quota/dquot.c:2370 vfs_load_quota_inode() warn: potential spectre issue 'dqopt->info' [w] (local cap) * fs/quota/quota.c:110 quota_getfmt() warn: potential spectre issue 'sb_dqopt(sb)->info' [r] * fs/quota/quota_v2.c:84 v2_check_quota_file() warn: potential spectre issue 'quota_magics' [w] * fs/quota/quota_v2.c:85 v2_check_quota_file() warn: potential spectre issue 'quota_versions' [w] * fs/quota/quota_v2.c:96 v2_read_file_info() warn: potential spectre issue 'dqopt->info' [r] * fs/quota/quota_v2.c:172 v2_write_file_info() warn: potential spectre issue 'dqopt->info' [r] Additionally, a quick inspection indicates there are array accesses with 'type' in quota_on() and quota_off() functions which are also addressed by this. Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: stable@vger.kernel.org Signed-off-by:
Jeremy Cline <jcline@redhat.com> Signed-off-by:
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Jeremy Cline authored
XQM_MAXQUOTAS and MAXQUOTAS are, it appears, equivalent. Replace all usage of XQM_MAXQUOTAS and remove it along with the unused XQM_*QUOTA definitions. Signed-off-by:
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- Jun 20, 2018
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Jan Kara authored
Use list_first_entry() and list_empty() instead of opencoded variants. Reviewed-by:
Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by:
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Greg Thelen authored
The dquots in the free_dquots list are not reclaimed in LRU way. put_dquot_last() puts entries to the tail and dqcache_shrink_scan() frees from the tail. Free unreferenced dquots in LRU order because it seems more reasonable than freeing most recently used. Signed-off-by:
Greg Thelen <gthelen@google.com> Signed-off-by:
Shakeel Butt <shakeelb@google.com> Signed-off-by:
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- Apr 09, 2018
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Jia-Ju Bai authored
dquot_init() is never called in atomic context. This function is only set as a parameter of fs_initcall(). Despite never getting called from atomic context, dquot_init() calls __get_free_pages() with GFP_ATOMIC, which waits busily for allocation. GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, to avoid busy waiting and improve the possibility of sucessful allocation. This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by:
Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by:
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- Apr 02, 2018
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Dominik Brodowski authored
While sys32_quotactl() is only needed on x86, it can use the recommended COMPAT_SYSCALL_DEFINEx() machinery for its setup. Acked-by:
Dominik Brodowski <linux@dominikbrodowski.net>
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Dominik Brodowski authored
Using the fs-internal kernel_quotactl() helper allows us to get rid of the fs-internal call to the sys_quotactl() syscall. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Acked-by:
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- Nov 29, 2017
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Tetsuo Handa authored
register_shrinker() might return -ENOMEM error since Linux 3.12. Call panic() as with other failure checks in this function if register_shrinker() failed. Fixes: 1d3d4437 ("vmscan: per-node deferred work") Signed-off-by:
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jan Kara <jack@suse.com> Cc: Michal Hocko <mhocko@suse.com> Reviewed-by:
Michal Hocko <mhocko@suse.com> Signed-off-by:
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- Nov 28, 2017
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Chao Yu authored
In commit 6184fc0b ("quota: Propagate error from ->acquire_dquot()"), we have propagated error from __dquot_initialize to caller, but we forgot to handle such error in add_dquot_ref(), so, currently, during quota accounting information initialization flow, if we failed for some of inodes, we just ignore such error, and do account for others, which is not a good implementation. In this patch, we choose to let user be aware of such error, so after turning on quota successfully, we can make sure all inodes disk usage can be accounted, which will be more reasonable. Suggested-by:
Chao Yu <yuchao0@huawei.com> Signed-off-by:
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- Nov 13, 2017
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Chao Yu authored
Commit 6184fc0b ("quota: Propagate error from ->acquire_dquot()") missed to handle error from dquot_initialize in dquot_file_open, fix it. Signed-off-by:
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- Nov 02, 2017
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Greg Kroah-Hartman authored
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by:
Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by:
Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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- Nov 01, 2017
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zhangyi (F) authored
In dquot_writeback_dquots(), we write back dquot from dirty dquots list. There is a potential infinite loop if ->write_dquot() failure and forget remove dquot from the list. This patch clear dirty bit anyway to avoid it. Signed-off-by:
zhangyi (F) <yi.zhang@huawei.com> Signed-off-by:
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- Oct 10, 2017
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Jan Kara authored
Eryu has reported that since commit 7b9ca4c6 "quota: Reduce contention on dq_data_lock" test generic/233 occasionally fails. This is caused by the fact that since that commit we don't generate warning and set grace time for quota allocations that have DQUOT_SPACE_NOFAIL set (these are for example some metadata allocations in ext4). We need these allocations to behave regularly wrt warning generation and grace time setting so fix the code to return to the original behavior. Reported-and-tested-by:
Eryu Guan <eguan@redhat.com> CC: stable@vger.kernel.org Fixes: 7b9ca4c6 Signed-off-by:
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- Sep 27, 2017
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Jan Kara authored
Eric has reported that since commit d2faa415 "quota: Do not acquire dqio_sem for dquot overwrites in v2 format" test generic/232 occasionally fails due to quota information being incorrect. Indeed that commit was too eager to remove dqio_sem completely from the path that just overwrites quota structure with updated information. Although that is innocent on its own, another process that inserts new quota structure to the same block can perform read-modify-write cycle of that block thus effectively discarding quota information update if they race in a wrong way. Fix the problem by acquiring dqio_sem for reading for overwrites of quota structure. Note that it *is* possible to completely avoid taking dqio_sem in the overwrite path however that will require modifying path inserting / deleting quota structures to avoid RMW cycles of the full block and for now it is not clear whether it is worth the hassle. Fixes: d2faa415 Reported-and-tested-by:
Eric Whitney <enwlinux@gmail.com> Signed-off-by:
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- Sep 18, 2017
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Konstantin Khlebnikov authored
Lock dq_dqb_lock around dquot_decr_inodes() Signed-off-by:
Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Fixes: 7b9ca4c6 ("quota: Reduce contention on dq_data_lock") Signed-off-by:
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- Aug 21, 2017
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Markus Elfring authored
Omit an extra message for a memory allocation failure in this function. This issue was detected by using the Coccinelle software. Signed-off-by:
Markus Elfring <elfring@users.sourceforge.net> Signed-off-by:
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- Aug 17, 2017
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Jan Kara authored
dq_data_lock is currently used to protect all modifications of quota accounting information, consistency of quota accounting on the inode, and dquot pointers from inode. As a result contention on the lock can be pretty heavy. Reduce the contention on the lock by protecting quota accounting information by a new dquot->dq_dqb_lock and consistency of quota accounting with inode usage by inode->i_lock. This change reduces time to create 500000 files on ext4 on ramdisk by 50 different processes in separate directories by 6% when user quota is turned on. When those 50 processes belong to 50 different users, the improvement is about 9%. Signed-off-by: -
Jan Kara authored
dquot_claim_reserved_space() and dquot_reclaim_reserved_space() have only a single callsite. Inline them there. Signed-off-by: -
Jan Kara authored
inode_incr_space() and inode_decr_space() have only two callsites. Inline them there as that will make locking changes simpler. Signed-off-by: -
Jan Kara authored
inode_add_rsv_space() and inode_sub_rsv_space() had only one callsite. Inline them there directly. inode_claim_rsv_space() and inode_reclaim_rsv_space() had two callsites so inline them there as well. This will simplify further locking changes. Signed-off-by: -
Jan Kara authored
Filesystems that are journalling quotas generally don't need tracking of dirty dquots in a list since forcing a transaction commit flushes all quotas anyway. Allow filesystem to say it doesn't want dquots to be tracked as it reduces contention on the dq_list_lock. Signed-off-by: -
Jan Kara authored
Currently every dquot carries a wait_queue_head_t used only when we are turning quotas off to wait for last users to drop dquot references. Since such rare case is not performance sensitive in any means, just use a global waitqueue for this and save space in struct dquot. Also convert the logic to use wait_event() instead of open-coding it. Signed-off-by: -
Jan Kara authored
Move locking of dq_list_lock into clear_dquot_dirty(). It makes the function more self-contained and will simplify our life later. Reviewed-by:
Andreas Dilger <adilger@dilger.ca> Signed-off-by:
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Jan Kara authored
Currently we mark dirty even dquots that are not active (i.e., initialization or reading failed for them). Thus later we have to check whether dirty dquot is really active and just clear the dirty bit if not. Avoid this complication by just never marking non-active dquot as dirty. Signed-off-by: -
Jan Kara authored
dqi_flags modifications are protected by dq_data_lock. However the modifications in vfs_load_quota_inode() and in mark_info_dirty() were not which could lead to corruption of dqi_flags. Since modifications to dqi_flags are rare, this is hard to observe in practice but in theory it could happen. Fix the problem by always using dq_data_lock for protection. Signed-off-by: -
Jan Kara authored
Currently we return -EIO on any error (or short read) from ->quota_read() while reading quota info. Propagate the error code instead. Suggested-by:
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Jan Kara authored
v2_read_file_info() returned -1 instead of proper error codes on error. Luckily this is not easily visible from userspace as we have called ->check_quota_file shortly before and thus already verified the quota file is sane. Still set the error codes to proper values. Reviewed-by:
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Jan Kara authored
Push down acquisition of dqio_sem into ->read_file_info() callback. This is for consistency with other operations and it also allows us to get rid of an ugliness in OCFS2. Reviewed-by:
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Jan Kara authored
Push down acquisition of dqio_sem into ->write_file_info() callback. Mostly for consistency with other operations. Reviewed-by:
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Jan Kara authored
Push down acquisition of dqio_sem into ->get_next_id() callback. Mostly for consistency with other operations. Reviewed-by:
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Jan Kara authored
Push down acquisition of dqio_sem into ->release_dqblk() callback. It will allow quota formats to decide whether they need it or not. Reviewed-by:
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Jan Kara authored
The old quota quota format has fixed offset in quota file based on ID so there's no locking needed against concurrent modifications of the file (locking against concurrent IO on the same dquot is still provided by dq_lock). Reviewed-by:
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Jan Kara authored
When dquot has space already allocated in a quota file, we just overwrite that place when writing dquot. So we don't need any protection against other modifications of quota file as these keep dquot in place. Reviewed-by:
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Jan Kara authored
Push down acquisition of dqio_sem into ->write_dqblk() callback. It will allow quota formats to decide whether they need it or not. Reviewed-by:
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Jan Kara authored
The old quota format has fixed offset in quota file based on ID so there's no locking needed against concurrent modifications of the file (locking against concurrent IO on the same dquot is still provided by dq_lock). Reviewed-by:
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Jan Kara authored
Push down acquisition of dqio_sem into ->read_dqblk() callback. It will allow quota formats to decide whether they need it or not. Reviewed-by:
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Jan Kara authored
Currently dquot writeout is only protected by dqio_sem held for writing. As we transition to a finer grained locking we will use dquot->dq_lock instead. So acquire it in dquot_commit() and move dqio_sem just around ->commit_dqblk() call as it is still needed to serialize quota file changes. Reviewed-by:
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Jan Kara authored
vfs_load_quota_inode() needs dqio_sem only for reading. In fact dqio_sem is not needed there at all since the function can be called only during quota on when quota file cannot be modified but let's leave the protection there since it is logical and the path is in no way performance critical. Reviewed-by:
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Jan Kara authored
dquot_get_next_id() needs dqio_sem only for reading to protect against racing with modification of quota file structure. Reviewed-by:
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