Qian Cai 6772387e82 ext4: fix a data race at inode->i_blocks ... commit 28936b62e7 upstream. inode->i_blocks could be accessed concurrently as noticed by KCSAN, BUG: KCSAN: data-race in ext4_do_update_inode [ext4] / inode_add_bytes write to 0xffff9a00d4b982d0 of 8 bytes by task 22100 on cpu 118: inode_add_bytes+0x65/0xf0 __inode_add_bytes at fs/stat.c:689 (inlined by) inode_add_bytes at fs/stat.c:702 ext4_mb_new_blocks+0x418/0xca0 [ext4] ext4_ext_map_blocks+0x1a6b/0x27b0 [ext4] ext4_map_blocks+0x1a9/0x950 [ext4] _ext4_get_block+0xfc/0x270 [ext4] ext4_get_block_unwritten+0x33/0x50 [ext4] __block_write_begin_int+0x22e/0xae0 __block_write_begin+0x39/0x50 ext4_write_begin+0x388/0xb50 [ext4] ext4_da_write_begin+0x35f/0x8f0 [ext4] generic_perform_write+0x15d/0x290 ext4_buffered_write_iter+0x11f/0x210 [ext4] ext4_file_write_iter+0xce/0x9e0 [ext4] new_sync_write+0x29c/0x3b0 __vfs_write+0x92/0xa0 vfs_write+0x103/0x260 ksys_write+0x9d/0x130 __x64_sys_write+0x4c/0x60 do_syscall_64+0x91/0xb05 entry_SYSCALL_64_after_hwframe+0x49/0xbe read to 0xffff9a00d4b982d0 of 8 bytes by task 8 on cpu 65: ext4_do_update_inode+0x4a0/0xf60 [ext4] ext4_inode_blocks_set at fs/ext4/inode.c:4815 ext4_mark_iloc_dirty+0xaf/0x160 [ext4] ext4_mark_inode_dirty+0x129/0x3e0 [ext4] ext4_convert_unwritten_extents+0x253/0x2d0 [ext4] ext4_convert_unwritten_io_end_vec+0xc5/0x150 [ext4] ext4_end_io_rsv_work+0x22c/0x350 [ext4] process_one_work+0x54f/0xb90 worker_thread+0x80/0x5f0 kthread+0x1cd/0x1f0 ret_from_fork+0x27/0x50 4 locks held by kworker/u256:0/8: #0: ffff9a025abc4328 ((wq_completion)ext4-rsv-conversion){+.+.}, at: process_one_work+0x443/0xb90 #1: ffffab5a862dbe20 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}, at: process_one_work+0x443/0xb90 #2: ffff9a025a9d0f58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2] #3: ffff9a00d4b985d8 (&(&ei->i_raw_lock)->rlock){+.+.}, at: ext4_do_update_inode+0xaa/0xf60 [ext4] irq event stamp: 3009267 hardirqs last enabled at (3009267): [<ffffffff980da9b7>] __find_get_block+0x107/0x790 hardirqs last disabled at (3009266): [<ffffffff980da8f9>] __find_get_block+0x49/0x790 softirqs last enabled at (3009230): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c softirqs last disabled at (3009223): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0 Reported by Kernel Concurrency Sanitizer on: CPU: 65 PID: 8 Comm: kworker/u256:0 Tainted: G L 5.6.0-rc2-next-20200221+ #7 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work [ext4] The plain read is outside of inode->i_lock critical section which results in a data race. Fix it by adding READ_ONCE() there. Link: https://lore.kernel.org/r/20200222043258.2279-1-cai@lca.pw Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-04-17 10:50:21 +02:00
..
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	ext4: add basic fs-verity support	2019-08-12 19:33:50 -07:00
acl.c	ext4: compare old and new mode before setting update_mode flag	2018-12-10 00:22:38 -05:00
acl.h	ext4: fix up remaining files with SPDX cleanups	2017-12-17 22:00:59 -05:00
balloc.c	ext4: fix potential race between online resizing and write operations	2020-02-28 17:22:22 +01:00
bitmap.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
block_validity.c	ext4: add cond_resched() to ext4_protect_reserved_inode	2020-02-19 19:52:59 +01:00
dir.c	ext4: fix checksum errors with indexed dirs	2020-02-19 19:52:59 +01:00
ext4.h	ext4: fix race between writepages and enabling EXT4_EXTENTS_FL	2020-02-28 17:22:23 +01:00
ext4_extents.h	ext4: adjust reserved cluster count when removing extents	2018-10-01 14:25:08 -04:00
ext4_jbd2.c	ext4: shutdown should not prevent get_write_access	2018-02-18 22:07:36 -05:00
ext4_jbd2.h	ext4: use jbd2_inode dirty range scoping	2019-06-20 17:26:26 -04:00
extents.c	ext4: fix warning inside ext4_convert_unwritten_extents_endio	2019-08-22 22:53:46 -04:00
extents_status.c	ext4: use percpu_counters for extent_status cache hits/misses	2019-08-28 11:19:23 -04:00
extents_status.h	ext4: use percpu_counters for extent_status cache hits/misses	2019-08-28 11:19:23 -04:00
file.c	ext4: fix ext4_dax_read/write inode locking sequence for IOCB_NOWAIT	2020-02-24 08:36:24 +01:00
fsmap.c	ext4: fix miscellaneous sparse warnings	2019-05-12 04:49:47 -04:00
fsmap.h	ext4: fix up remaining files with SPDX cleanups	2017-12-17 22:00:59 -05:00
fsync.c	Revert "ext4: use ext4_write_inode() when fsyncing w/o a journal"	2019-01-31 23:41:11 -05:00
hash.c	ext4: fix kernel oops caused by spurious casefold flag	2019-09-03 01:43:17 -04:00
ialloc.c	ext4: fix potential race between s_flex_groups online resizing and access	2020-02-28 17:22:22 +01:00
indirect.c	ext4: clean up kerneldoc warnigns when building with W=1	2019-06-19 16:30:03 -04:00
inline.c	ext4: set error return correctly when ext4_htree_store_dirent fails	2019-08-12 14:29:38 -04:00
inode.c	ext4: fix a data race at inode->i_blocks	2020-04-17 10:50:21 +02:00
ioctl.c	Added new ext4 debugging ioctls to allow userspace to get information	2019-09-21 13:37:39 -07:00
mballoc.c	ext4: fix potential race between s_flex_groups online resizing and access	2020-02-28 17:22:22 +01:00
mballoc.h	ext4: fix up remaining files with SPDX cleanups	2017-12-17 22:00:59 -05:00
migrate.c	ext4: fix race between writepages and enabling EXT4_EXTENTS_FL	2020-02-28 17:22:23 +01:00
mmp.c	ext4: don't assume that mmp_nodename/bdevname have NUL	2020-02-19 19:52:58 +01:00
move_extent.c	ext4: use jbd2_inode dirty range scoping	2019-06-20 17:26:26 -04:00
namei.c	ext4: add cond_resched() to __ext4_find_entry()	2020-02-28 17:22:22 +01:00
page-io.c	ext4: fix deadlock allocating crypto bounce page from mempool	2020-02-11 04:35:32 -08:00
readpage.c	ext4: fix deadlock allocating bio_post_read_ctx from mempool	2020-02-24 08:36:29 +01:00
resize.c	ext4: fix potential race between s_flex_groups online resizing and access	2020-02-28 17:22:22 +01:00
super.c	ext4: potential crash on allocation error in ext4_alloc_flex_bg_array()	2020-03-05 16:43:41 +01:00
symlink.c	ext4: switch to fscrypt_get_symlink()	2018-01-11 22:10:40 -05:00
sysfs.c	ext4: add basic fs-verity support	2019-08-12 19:33:50 -07:00
truncate.h	ext4: handle layout changes to pinned DAX mappings	2018-07-29 17:00:22 -04:00
verity.c	ext4: add basic fs-verity support	2019-08-12 19:33:50 -07:00
xattr.c	ext4: ignore e_value_offs for xattrs with value-in-ea-inode	2019-04-10 00:37:36 -04:00
xattr.h	ext4: add extra checks to ext4_xattr_block_get()	2018-03-30 20:04:11 -04:00
xattr_security.c	ext4: use XATTR_CREATE in ext4_initxattrs()	2018-05-10 11:52:14 -04:00
xattr_trusted.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
xattr_user.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00