BMC/Intel-BMC/linux.git/fs/f2fs/segment.c, branch dev-5.2

f2fs: avoid out-of-range memory access

2019-07-31T05:24:52+00:00

[ Upstream commit 56f3ce675103e3fb9e631cfb4131fc768bc23e9a ] blkoff_off might over 512 due to fs corrupt or security vulnerability. That should be checked before being using. Use ENTRIES_IN_SUM to protect invalid value in cur_data_blkoff. Signed-off-by: Ocean Chen Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to avoid long latency during umount

2019-07-31T05:24:52+00:00

[ Upstream commit 6e0cd4a9dd4df1a0afcb454f1e654b5c80685913 ] In umount, we give an constand time to handle pending discard, previously, in __issue_discard_cmd() we missed to check timeout condition in loop, result in delaying long time, fix it. Signed-off-by: Heng Xiao [Chao Yu: add commit message] Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: Lower threshold for disable_cp_again

2019-07-31T05:24:36+00:00

[ Upstream commit ae4ad7ea09d32ff1b6fb908ff12f8c1bd5241b29 ] The existing threshold for allowable holes at checkpoint=disable time is too high. The OVP space contains reserved segments, which are always in the form of free segments. These must be subtracted from the OVP value. The current threshold is meant to be the maximum value of holes of a single type we can have and still guarantee that we can fill the disk without failing to find space for a block of a given type. If the disk is full, ignoring current reserved, which only helps us, the amount of unused blocks is equal to the OVP area. Of that, there are reserved segments, which must be free segments, and the rest of the ovp area, which can come from either free segments or holes. The maximum possible amount of holes is OVP-reserved. Now, consider the disk when mounting with checkpoint=disable. We must be able to fill all available free space with either data or node blocks. When we start with checkpoint=disable, holes are locked to their current type. Say we have H of one type of hole, and H+X of the other. We can fill H of that space with arbitrary typed blocks via SSR. For the remaining H+X blocks, we may not have any of a given block type left at all. For instance, if we were to fill the disk entirely with blocks of the type with fewer holes, the H+X blocks of the opposite type would not be used. If H+X > OVP-reserved, there would be more holes than could possibly exist, and we would have failed to find a suitable block earlier on, leading to a crash in update_sit_entry. If H+X <= OVP-reserved, then the holes end up effectively masked by the OVP region in this case. Signed-off-by: Daniel Rosenberg Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to avoid deadloop if data_flush is on

2019-07-31T05:24:33+00:00

[ Upstream commit 040d2bb318d1aea4f28cc22504b44e446666c86e ] As Hagbard Celine reported: [ 615.697824] INFO: task kworker/u16:5:344 blocked for more than 120 seconds. [ 615.697825] Not tainted 5.0.15-gentoo-f2fslog #4 [ 615.697826] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 615.697827] kworker/u16:5 D 0 344 2 0x80000000 [ 615.697831] Workqueue: writeback wb_workfn (flush-259:0) [ 615.697832] Call Trace: [ 615.697836] ? __schedule+0x2c5/0x8b0 [ 615.697839] schedule+0x32/0x80 [ 615.697841] schedule_preempt_disabled+0x14/0x20 [ 615.697842] __mutex_lock.isra.8+0x2ba/0x4d0 [ 615.697845] ? log_store+0xf5/0x260 [ 615.697848] f2fs_write_data_pages+0x133/0x320 [ 615.697851] ? trace_hardirqs_on+0x2c/0xe0 [ 615.697854] do_writepages+0x41/0xd0 [ 615.697857] __filemap_fdatawrite_range+0x81/0xb0 [ 615.697859] f2fs_sync_dirty_inodes+0x1dd/0x200 [ 615.697861] f2fs_balance_fs_bg+0x2a7/0x2c0 [ 615.697863] ? up_read+0x5/0x20 [ 615.697865] ? f2fs_do_write_data_page+0x2cb/0x940 [ 615.697867] f2fs_balance_fs+0xe5/0x2c0 [ 615.697869] __write_data_page+0x1c8/0x6e0 [ 615.697873] f2fs_write_cache_pages+0x1e0/0x450 [ 615.697878] f2fs_write_data_pages+0x14b/0x320 [ 615.697880] ? trace_hardirqs_on+0x2c/0xe0 [ 615.697883] do_writepages+0x41/0xd0 [ 615.697885] __filemap_fdatawrite_range+0x81/0xb0 [ 615.697887] f2fs_sync_dirty_inodes+0x1dd/0x200 [ 615.697889] f2fs_balance_fs_bg+0x2a7/0x2c0 [ 615.697891] f2fs_write_node_pages+0x51/0x220 [ 615.697894] do_writepages+0x41/0xd0 [ 615.697897] __writeback_single_inode+0x3d/0x3d0 [ 615.697899] writeback_sb_inodes+0x1e8/0x410 [ 615.697902] __writeback_inodes_wb+0x5d/0xb0 [ 615.697904] wb_writeback+0x28f/0x340 [ 615.697906] ? cpumask_next+0x16/0x20 [ 615.697908] wb_workfn+0x33e/0x420 [ 615.697911] process_one_work+0x1a1/0x3d0 [ 615.697913] worker_thread+0x30/0x380 [ 615.697915] ? process_one_work+0x3d0/0x3d0 [ 615.697916] kthread+0x116/0x130 [ 615.697918] ? kthread_create_worker_on_cpu+0x70/0x70 [ 615.697921] ret_from_fork+0x3a/0x50 There is still deadloop in below condition: d A - do_writepages - f2fs_write_node_pages - f2fs_balance_fs_bg - f2fs_sync_dirty_inodes - f2fs_write_cache_pages - mutex_lock(&sbi->writepages) -- lock once - __write_data_page - f2fs_balance_fs_bg - f2fs_sync_dirty_inodes - f2fs_write_data_pages - mutex_lock(&sbi->writepages) -- lock again Thread A Thread B - do_writepages - f2fs_write_node_pages - f2fs_balance_fs_bg - f2fs_sync_dirty_inodes - .cp_task = current - f2fs_sync_dirty_inodes - .cp_task = current - filemap_fdatawrite - .cp_task = NULL - filemap_fdatawrite - f2fs_write_cache_pages - enter f2fs_balance_fs_bg since .cp_task is NULL - .cp_task = NULL Change as below to avoid this: - add condition to avoid holding .writepages mutex lock in path of data flush - introduce mutex lock sbi.flush_lock to exclude concurrent data flush in background. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to avoid potential race on sbi->unusable_block_count access/update

2019-05-09T04:23:13+00:00

Use sbi.stat_lock to protect sbi->unusable_block_count accesss/udpate, in order to avoid potential race on it. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: introduce DATA_GENERIC_ENHANCE

2019-05-09T04:23:13+00:00

Previously, f2fs_is_valid_blkaddr(, blkaddr, DATA_GENERIC) will check whether @blkaddr locates in main area or not. That check is weak, since the block address in range of main area can point to the address which is not valid in segment info table, and we can not detect such condition, we may suffer worse corruption as system continues running. So this patch introduce DATA_GENERIC_ENHANCE to enhance the sanity check which trigger SIT bitmap check rather than only range check. This patch did below changes as wel: - set SBI_NEED_FSCK in f2fs_is_valid_blkaddr(). - get rid of is_valid_data_blkaddr() to avoid panic if blkaddr is invalid. - introduce verify_fio_blkaddr() to wrap fio {new,old}_blkaddr validation check. - spread blkaddr check in: * f2fs_get_node_info() * __read_out_blkaddrs() * f2fs_submit_page_read() * ra_data_block() * do_recover_data() This patch can fix bug reported from bugzilla below: https://bugzilla.kernel.org/show_bug.cgi?id=203215 https://bugzilla.kernel.org/show_bug.cgi?id=203223 https://bugzilla.kernel.org/show_bug.cgi?id=203231 https://bugzilla.kernel.org/show_bug.cgi?id=203235 https://bugzilla.kernel.org/show_bug.cgi?id=203241 = Update by Jaegeuk Kim = DATA_GENERIC_ENHANCE enhanced to validate block addresses on read/write paths. But, xfstest/generic/446 compalins some generated kernel messages saying invalid bitmap was detected when reading a block. The reaons is, when we get the block addresses from extent_cache, there is no lock to synchronize it from truncating the blocks in parallel. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix to avoid panic in f2fs_inplace_write_data()

2019-05-09T04:23:09+00:00

As Jungyeon reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203239 - Overview When mounting the attached crafted image and running program, following errors are reported. Additionally, it hangs on sync after running program. The image is intentionally fuzzed from a normal f2fs image for testing. Compile options for F2FS are as follows. CONFIG_F2FS_FS=y CONFIG_F2FS_STAT_FS=y CONFIG_F2FS_FS_XATTR=y CONFIG_F2FS_FS_POSIX_ACL=y CONFIG_F2FS_CHECK_FS=y - Reproduces cc poc_15.c ./run.sh f2fs sync - Kernel messages ------------[ cut here ]------------ kernel BUG at fs/f2fs/segment.c:3162! RIP: 0010:f2fs_inplace_write_data+0x12d/0x160 Call Trace: f2fs_do_write_data_page+0x3c1/0x820 __write_data_page+0x156/0x720 f2fs_write_cache_pages+0x20d/0x460 f2fs_write_data_pages+0x1b4/0x300 do_writepages+0x15/0x60 __filemap_fdatawrite_range+0x7c/0xb0 file_write_and_wait_range+0x2c/0x80 f2fs_do_sync_file+0x102/0x810 do_fsync+0x33/0x60 __x64_sys_fsync+0xb/0x10 do_syscall_64+0x43/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The reason is f2fs_inplace_write_data() will trigger kernel panic due to data block locates in node type segment. To avoid panic, let's just return error code and set SBI_NEED_FSCK to give a hint to fsck for latter repairing. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: improve discard handling with multi-device volumes

2019-04-05T16:33:55+00:00

f2fs_hw_support_discard() only tests if the super block device supports discard. However, for a multi-device volume, not all disks used may support discard. Improve the check performed to test all devices of the volume and report discard as supported if at least one device of the volume supports discard. To implement this, introduce the helper function f2fs_bdev_support_discard(), which returns true for zoned block devices (where discard is processed as a zone reset) and for regular disks supporting the discard command. f2fs_bdev_support_discard() is also used in __queue_discard_cmd() to handle discard command issuing for a particular device of the volume. That is, prevent issuing a discard command for block devices that do not support it. Signed-off-by: Damien Le Moal Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: Reduce zoned block device memory usage

2019-04-05T16:33:55+00:00

For zoned block devices, an array of zone types for each device is allocated and initialized in order to determine if a section is stored on a sequential zone (zone reset needed) or a conventional zone (no zone reset needed and regular discard applies). Considering this usage, the zone types stored in memory can be replaced with a bitmap to indicate an equivalent information, that is, if a zone is sequential or not. This reduces the memory usage for each zoned device by roughly 8: on a 14TB disk with zones of 256 MB, the zone type array consumes 13x4KB pages while the bitmap uses only 2x4KB pages. This patch changes the f2fs_dev_info structure blkz_type field to the bitmap blkz_seq. Access to this bitmap is done using the helper function f2fs_blkz_is_seq(), which is a rewrite of the function get_blkz_type(). Signed-off-by: Damien Le Moal Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: Fix use of number of devices

2019-04-05T16:33:54+00:00

For a single device mount using a zoned block device, the zone information for the device is stored in the sbi->devs single entry array and sbi->s_ndevs is set to 1. This differs from a single device mount using a regular block device which does not allocate sbi->devs and sets sbi->s_ndevs to 0. However, sbi->s_devs == 0 condition is used throughout the code to differentiate a single device mount from a multi-device mount where sbi->s_ndevs is always larger than 1. This results in problems with single zoned block device volumes as these are treated as multi-device mounts but do not have the start_blk and end_blk information set. One of the problem observed is skipping of zone discard issuing resulting in write commands being issued to full zones or unaligned to a zone write pointer. Fix this problem by simply treating the cases sbi->s_ndevs == 0 (single regular block device mount) and sbi->s_ndevs == 1 (single zoned block device mount) in the same manner. This is done by introducing the helper function f2fs_is_multi_device() and using this helper in place of direct tests of sbi->s_ndevs value, improving code readability. Fixes: 7bb3a371d199 ("f2fs: Fix zoned block device support") Cc: Signed-off-by: Damien Le Moal Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim