- Jan 11, 2022
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Zhihao Cheng authoredMM defined the rule [1] very clearly that once page was set with PG_private flag, we should increment the refcount in that page, also main flows like pageout(), migrate_page() will assume there is one additional page reference count if page_has_private() returns true. Otherwise, we may get a BUG in page migration: page:0000000080d05b9d refcount:-1 mapcount:0 mapping:000000005f4d82a8 index:0xe2 pfn:0x14c12 aops:ubifs_file_address_operations [ubifs] ino:8f1 dentry name:"f30e" flags: 0x1fffff80002405(locked|uptodate|owner_priv_1|private|node=0| zone=1|lastcpupid=0x1fffff) page dumped because: VM_BUG_ON_PAGE(page_count(page) != 0) ------------[ cut here ]------------ kernel BUG at include/linux/page_ref.h:184! invalid opcode: 0000 [#1] SMP CPU: 3 PID: 38 Comm: kcompactd0 Not tainted 5.15.0-rc5 RIP: 0010:migrate_page_move_mapping+0xac3/0xe70 Call Trace: ubifs_migrate_page+0x22/0xc0 [ubifs] move_to_new_page+0xb4/0x600 migrate_pages+0x1523/0x1cc0 compact_zone+0x8c5/0x14b0 kcompactd+0x2bc/0x560 kthread+0x18c/0x1e0 ret_from_fork+0x1f/0x30 Before the time, we should make clean a concept, what does refcount means in page gotten from grab_cache_page_write_begin(). There are 2 situations: Situation 1: refcount is 3, page is created by __page_cache_alloc. TYPE_A - the write process is using this page TYPE_B - page is assigned to one certain mapping by calling __add_to_page_cache_locked() TYPE_C - page is added into pagevec list corresponding current cpu by calling lru_cache_add() Situation 2: refcount is 2, page is gotten from the mapping's tree TYPE_B - page has been assigned to one certain mapping TYPE_A - the write process is using this page (by calling page_cache_get_speculative()) Filesystem releases one refcount by calling put_page() in xxx_write_end(), the released refcount corresponds to TYPE_A (write task is using it). If there are any processes using a page, page migration process will skip the page by judging whether expected_page_refs() equals to page refcount. The BUG is caused by following process: PA(cpu 0) kcompactd(cpu 1) compact_zone ubifs_write_begin page_a = grab_cache_page_write_begin add_to_page_cache_lru lru_cache_add pagevec_add // put page into cpu 0's pagevec (refcnf = 3, for page creation process) ubifs_write_end SetPagePrivate(page_a) // doesn't increase page count ! unlock_page(page_a) put_page(page_a) // refcnt = 2 [...] PB(cpu 0) filemap_read filemap_get_pages add_to_page_cache_lru lru_cache_add __pagevec_lru_add // traverse all pages in cpu 0's pagevec __pagevec_lru_add_fn SetPageLRU(page_a) isolate_migratepages isolate_migratepages_block get_page_unless_zero(page_a) // refcnt = 3 list_add(page_a, from_list) migrate_pages(from_list) __unmap_and_move move_to_new_page ubifs_migrate_page(page_a) migrate_page_move_mapping expected_page_refs get 3 (migration[1] + mapping[1] + private[1]) release_pages put_page_testzero(page_a) // refcnt = 3 page_ref_freeze // refcnt = 0 page_ref_dec_and_test(0 - 1 = -1) page_ref_unfreeze VM_BUG_ON_PAGE(-1 != 0, page) UBIFS doesn't increase the page refcount after setting private flag, which leads to page migration task believes the page is not used by any other processes, so the page is migrated. This causes concurrent accessing on page refcount between put_page() called by other process(eg. read process calls lru_cache_add) and page_ref_unfreeze() called by migration task. Actually zhangjun has tried to fix this problem [2] by recalculating page refcnt in ubifs_migrate_page(). It's better to follow MM rules [1], because just like Kirill suggested in [2], we need to check all users of page_has_private() helper. Like f2fs does in [3], fix it by adding/deleting refcount when setting/clearing private for a page. BTW, according to [4], we set 'page->private' as 1 because ubifs just simply SetPagePrivate(). And, [5] provided a common helper to set/clear page private, ubifs can use this helper following the example of iomap, afs, btrfs, etc. Jump [6] to find a reproducer. [1] https://lore.kernel.org/lkml/2b19b3c4-2bc4-15fa-15cc-27a13e5c7af1@aol.com [2] https://www.spinics.net/lists/linux-mtd/msg04018.html [3] http://lkml.iu.edu/hypermail/linux/kernel/1903.0/03313.html [4] https://lore.kernel.org/linux-f2fs-devel/20210422154705.GO3596236@casper.infradead.org [5] https://lore.kernel.org/all/20200517214718.468-1-guoqing.jiang@cloud.ionos.com [6] https://bugzilla.kernel.org/show_bug.cgi?id=214961 Fixes: 1e51764a ("UBIFS: add new flash file system") Signed-off-by:
Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
Function ubifs_wbuf_write_nolock() may access buf out of bounds in following process: ubifs_wbuf_write_nolock(): aligned_len = ALIGN(len, 8); // Assume len = 4089, aligned_len = 4096 if (aligned_len <= wbuf->avail) ... // Not satisfy if (wbuf->used) { ubifs_leb_write() // Fill some data in avail wbuf len -= wbuf->avail; // len is still not 8-bytes aligned aligned_len -= wbuf->avail; } n = aligned_len >> c->max_write_shift; if (n) { n <<= c->max_write_shift; err = ubifs_leb_write(c, wbuf->lnum, buf + written, wbuf->offs, n); // n > len, read out of bounds less than 8(n-len) bytes } , which can be catched by KASAN: ========================================================= BUG: KASAN: slab-out-of-bounds in ecc_sw_hamming_calculate+0x1dc/0x7d0 Read of size 4 at addr ffff888105594ff8 by task kworker/u8:4/128 Workqueue: writeback wb_workfn (flush-ubifs_0_0) Call Trace: kasan_report.cold+0x81/0x165 nand_write_page_swecc+0xa9/0x160 ubifs_leb_write+0xf2/0x1b0 [ubifs] ubifs_wbuf_write_nolock+0x421/0x12c0 [ubifs] write_head+0xdc/0x1c0 [ubifs] ubifs_jnl_write_inode+0x627/0x960 [ubifs] wb_workfn+0x8af/0xb80 Function ubifs_wbuf_write_nolock() accepts that parameter 'len' is not 8 bytes aligned, the 'len' represents the true length of buf (which is allocated in 'ubifs_jnl_xxx', eg. ubifs_jnl_write_inode), so ubifs_wbuf_write_nolock() must handle the length read from 'buf' carefully to write leb safely. Fetch a reproducer in [Link]. Fixes: 1e51764a ("UBIFS: add new flash file system") Link: https://bugzilla.kernel.org/show_bug.cgi?id=214785 Reported-by:Chengsong Ke <kechengsong@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
Make 'ui->data_len' aligned with 8 bytes before it is assigned to dirtied_ino_d. Since 8871d84c("ubifs: convert to fileattr") applied, 'setflags()' only affects regular files and directories, only xattr inode, symlink inode and special inode(pipe/char_dev/block_dev) have none- zero 'ui->data_len' field, so assertion '!(req->dirtied_ino_d & 7)' cannot fail in ubifs_budget_space(). To avoid assertion fails in future evolution(eg. setflags can operate special inodes), it's better to make dirtied_ino_d 8 bytes aligned, after all aligned size is still zero for regular files. Fixes: 1e51764a ("UBIFS: add new flash file system") Signed-off-by:
Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
UBIFS should make sure the flash has enough space to store dirty (Data that is newer than disk) data (in memory), space budget is exactly designed to do that. If space budget calculates less data than we need, 'make_reservation()' will do more work(return -ENOSPC if no free space lelf, sometimes we can see "cannot reserve xxx bytes in jhead xxx, error -28" in ubifs error messages) with ubifs inodes locked, which may effect other syscalls. A simple way to decide how much space do we need when make a budget: See how much space is needed by 'make_reservation()' in ubifs_jnl_xxx() function according to corresponding operation. It's better to report ENOSPC in ubifs_budget_space(), as early as we can. Fixes: 474b9370 ("ubifs: Implement O_TMPFILE") Fixes: 1e51764a ("UBIFS: add new flash file system") Signed-off-by:
Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
'ui->dirty' is not protected by 'ui_mutex' in function do_tmpfile() which may race with ubifs_write_inode[wb_workfn] to access/update 'ui->dirty', finally dirty space is released twice. open(O_TMPFILE) wb_workfn do_tmpfile ubifs_budget_space(ino_req = { .dirtied_ino = 1}) d_tmpfile // mark inode(tmpfile) dirty ubifs_jnl_update // without holding tmpfile's ui_mutex mark_inode_clean(ui) if (ui->dirty) ubifs_release_dirty_inode_budget(ui) // release first time ubifs_write_inode mutex_lock(&ui->ui_mutex) ubifs_release_dirty_inode_budget(ui) // release second time mutex_unlock(&ui->ui_mutex) ui->dirty = 0 Run generic/476 can reproduce following message easily (See reproducer in [Link]): UBIFS error (ubi0:0 pid 2578): ubifs_assert_failed [ubifs]: UBIFS assert failed: c->bi.dd_growth >= 0, in fs/ubifs/budget.c:554 UBIFS warning (ubi0:0 pid 2578): ubifs_ro_mode [ubifs]: switched to read-only mode, error -22 Workqueue: writeback wb_workfn (flush-ubifs_0_0) Call Trace: ubifs_ro_mode+0x54/0x60 [ubifs] ubifs_assert_failed+0x4b/0x80 [ubifs] ubifs_release_budget+0x468/0x5a0 [ubifs] ubifs_release_dirty_inode_budget+0x53/0x80 [ubifs] ubifs_write_inode+0x121/0x1f0 [ubifs] ... wb_workfn+0x283/0x7b0 Fix it by holding tmpfile ubifs inode lock during ubifs_jnl_update(). Similar problem exists in whiteout renaming, but previous fix("ubifs: Rename whiteout atomically") has solved the problem. Fixes: 474b9370 ("ubifs: Implement O_TMPFILE") Link: https://bugzilla.kernel.org/show_bug.cgi?id=214765 Signed-off-by:Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
Currently, rename whiteout has 3 steps: 1. create tmpfile(which associates old dentry to tmpfile inode) for whiteout, and store tmpfile to disk 2. link whiteout, associate whiteout inode to old dentry agagin and store old dentry, old inode, new dentry on disk 3. writeback dirty whiteout inode to disk Suddenly power-cut or error occurring(eg. ENOSPC returned by budget, memory allocation failure) during above steps may cause kinds of problems: Problem 1: ENOSPC returned by whiteout space budget (before step 2), old dentry will disappear after rename syscall, whiteout file cannot be found either. ls dir // we get file, whiteout rename(dir/file, dir/whiteout, REANME_WHITEOUT) ENOSPC = ubifs_budget_space(&wht_req) // return ls dir // empty (no file, no whiteout) Problem 2: Power-cut happens before step 3, whiteout inode with 'nlink=1' is not stored on disk, whiteout dentry(old dentry) is written on disk, whiteout file is lost on next mount (We get "dead directory entry" after executing 'ls -l' on whiteout file). Now, we use following 3 steps to finish rename whiteout: 1. create an in-mem inode with 'nlink = 1' as whiteout 2. ubifs_jnl_rename (Write on disk to finish associating old dentry to whiteout inode, associating new dentry with old inode) 3. iput(whiteout) Rely writing in-mem inode on disk by ubifs_jnl_rename() to finish rename whiteout, which avoids middle disk state caused by suddenly power-cut and error occurring. Fixes: 9e0a1fff ("ubifs: Implement RENAME_WHITEOUT") Signed-off-by:Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
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- Jan 10, 2022
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Zhihao Cheng authored
whiteout inode should be put when do_tmpfile() failed if inode has been initialized. Otherwise we will get following warning during umount: UBIFS error (ubi0:0 pid 1494): ubifs_assert_failed [ubifs]: UBIFS assert failed: c->bi.dd_growth == 0, in fs/ubifs/super.c:1930 VFS: Busy inodes after unmount of ubifs. Self-destruct in 5 seconds. Fixes: 9e0a1fff ("ubifs: Implement RENAME_WHITEOUT") Signed-off-by:
Zhihao Cheng <chengzhihao1@huawei.com>
Suggested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
Since 9ec64962("ubifs: Implement RENAME_EXCHANGE") and 9e0a1fff ("ubifs: Implement RENAME_WHITEOUT") are applied, ubifs_rename locks and changes 4 ubifs inodes, correct the comment for ui_mutex in ubifs_inode. Signed-off-by:
Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
Following hung tasks: [ 77.028764] task:kworker/u8:4 state:D stack: 0 pid: 132 [ 77.028820] Call Trace: [ 77.029027] schedule+0x8c/0x1b0 [ 77.029067] mutex_lock+0x50/0x60 [ 77.029074] ubifs_write_inode+0x68/0x1f0 [ubifs] [ 77.029117] __writeback_single_inode+0x43c/0x570 [ 77.029128] writeback_sb_inodes+0x259/0x740 [ 77.029148] wb_writeback+0x107/0x4d0 [ 77.029163] wb_workfn+0x162/0x7b0 [ 92.390442] task:aa state:D stack: 0 pid: 1506 [ 92.390448] Call Trace: [ 92.390458] schedule+0x8c/0x1b0 [ 92.390461] wb_wait_for_completion+0x82/0xd0 [ 92.390469] __writeback_inodes_sb_nr+0xb2/0x110 [ 92.390472] writeback_inodes_sb_nr+0x14/0x20 [ 92.390476] ubifs_budget_space+0x705/0xdd0 [ubifs] [ 92.390503] do_rename.cold+0x7f/0x187 [ubifs] [ 92.390549] ubifs_rename+0x8b/0x180 [ubifs] [ 92.390571] vfs_rename+0xdb2/0x1170 [ 92.390580] do_renameat2+0x554/0x770 , are caused by concurrent rename whiteout and inode writeback processes: rename_whiteout(Thread 1) wb_workfn(Thread2) ubifs_rename do_rename lock_4_inodes (Hold ui_mutex) ubifs_budget_space make_free_space shrink_liability __writeback_inodes_sb_nr bdi_split_work_to_wbs (Queue new wb work) wb_do_writeback(wb work) __writeback_single_inode ubifs_write_inode LOCK(ui_mutex) ↑ wb_wait_for_completion (Wait wb work) <-- deadlock! Reproducer (Detail program in [Link]): 1. SYS_renameat2("/mp/dir/file", "/mp/dir/whiteout", RENAME_WHITEOUT) 2. Consume out of space before kernel(mdelay) doing budget for whiteout Fix it by doing whiteout space budget before locking ubifs inodes. BTW, it also fixes wrong goto tag 'out_release' in whiteout budget error handling path(It should at least recover dir i_size and unlock 4 ubifs inodes). Fixes: 9e0a1fff ("ubifs: Implement RENAME_WHITEOUT") Link: https://bugzilla.kernel.org/show_bug.cgi?id=214733 Signed-off-by:Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Zhihao Cheng authored
'whiteout_ui->data' will be freed twice if space budget fail for rename whiteout operation as following process: rename_whiteout dev = kmalloc whiteout_ui->data = dev kfree(whiteout_ui->data) // Free first time iput(whiteout) ubifs_free_inode kfree(ui->data) // Double free! KASAN reports: ================================================================== BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70 Call Trace: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f Allocated by task 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 Freed by task 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8 ================================================================== Let ubifs_free_inode() free 'whiteout_ui->data'. BTW, delete unused assignment 'whiteout_ui->data_len = 0', process 'ubifs_evict_inode() -> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode()' doesn't need it (because 'inc_nlink(whiteout)' won't be excuted by 'goto out_release', and the nlink of whiteout inode is 0). Fixes: 9e0a1fff ("ubifs: Implement RENAME_WHITEOUT") Signed-off-by:Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Baokun Li authored
Hulk Robot reported a KASAN report about use-after-free: ================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160 Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385 [...] Call Trace: klist_dec_and_del+0xa7/0x4a0 klist_put+0xc7/0x1a0 device_del+0x4d4/0xed0 cdev_device_del+0x1a/0x80 ubi_attach_mtd_dev+0x2951/0x34b0 [ubi] ctrl_cdev_ioctl+0x286/0x2f0 [ubi] Allocated by task 1414: device_add+0x60a/0x18b0 cdev_device_add+0x103/0x170 ubi_create_volume+0x1118/0x1a10 [ubi] ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi] Freed by task 1385: cdev_device_del+0x1a/0x80 ubi_remove_volume+0x438/0x6c0 [ubi] ubi_cdev_ioctl+0xbf4/0x1ba0 [ubi] [...] ================================================================== The lock held by ctrl_cdev_ioctl is ubi_devices_mutex, but the lock held by ubi_cdev_ioctl is ubi->device_mutex. Therefore, the two locks can be concurrent. ctrl_cdev_ioctl contains two operations: ubi_attach and ubi_detach. ubi_detach is bug-free because it uses reference counting to prevent concurrency. However, uif_init and uif_close in ubi_attach may race with ubi_cdev_ioctl. uif_init will race with ubi_cdev_ioctl as in the following stack. cpu1 cpu2 cpu3 _______________________|________________________|______________________ ctrl_cdev_ioctl ubi_attach_mtd_dev uif_init ubi_cdev_ioctl ubi_create_volume cdev_device_add ubi_add_volume // sysfs exist kill_volumes ubi_cdev_ioctl ubi_remove_volume cdev_device_del // first free ubi_free_volume cdev_del // double free cdev_device_del And uif_close will race with ubi_cdev_ioctl as in the following stack. cpu1 cpu2 cpu3 _______________________|________________________|______________________ ctrl_cdev_ioctl ubi_attach_mtd_dev uif_init ubi_cdev_ioctl ubi_create_volume cdev_device_add ubi_debugfs_init_dev //error goto out_uif; uif_close kill_volumes ubi_cdev_ioctl ubi_remove_volume cdev_device_del // first free ubi_free_volume // double free The cause of this problem is that commit 714fb87e make device "available" before it becomes accessible via sysfs. Therefore, we roll back the modification. We will fix the race condition between ubi device creation and udev by removing ubi_get_device in vol_attribute_show and dev_attribute_show.This avoids accessing uninitialized ubi_devices[ubi_num]. ubi_get_device is used to prevent devices from being deleted during sysfs execution. However, now kernfs ensures that devices will not be deleted before all reference counting are released. The key process is shown in the following stack. device_del device_remove_attrs device_remove_groups sysfs_remove_groups sysfs_remove_group remove_files kernfs_remove_by_name kernfs_remove_by_name_ns __kernfs_remove kernfs_drain Fixes: 714fb87e ("ubi: Fix race condition between ubi device creation and udev") Reported-by:Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
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- Dec 24, 2021
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Kyeong Yoo authored
GC task can deadlock in read_cache_page() because it may attempt to release a page that is actually allocated by another task in jffs2_write_begin(). The reason is that in jffs2_write_begin() there is a small window a cache page is allocated for use but not set Uptodate yet. This ends up with a deadlock between two tasks: 1) A task (e.g. file copy) - jffs2_write_begin() locks a cache page - jffs2_write_end() tries to lock "alloc_sem" from jffs2_reserve_space() <-- STUCK 2) GC task (jffs2_gcd_mtd3) - jffs2_garbage_collect_pass() locks "alloc_sem" - try to lock the same cache page in read_cache_page() <-- STUCK So to avoid this deadlock, hold "alloc_sem" in jffs2_write_begin() while reading data in a cache page. Signed-off-by:
Kyeong Yoo <kyeong.yoo@alliedtelesis.co.nz>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Baokun Li authored
If ubifs_garbage_collect_leb() returns -EAGAIN and ubifs_return_leb returns error, a LEB will always has a "taken" flag. In this case, set the ubifs to read-only to prevent a worse situation. Signed-off-by:
Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Baokun Li authored
If ubifs_garbage_collect_leb() returns -EAGAIN and enters the "out" branch, ubifs_return_leb will execute twice on the same lnum. This can cause data loss in concurrency situations. Reported-by:
Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Baokun Li authored
Hulk Robot reported a KASAN report about slab-out-of-bounds: ================================================================== BUG: KASAN: slab-out-of-bounds in ubifs_change_lp+0x3a9/0x1390 [ubifs] Read of size 8 at addr ffff888101c961f8 by task fsstress/1068 [...] Call Trace: check_memory_region+0x1c1/0x1e0 ubifs_change_lp+0x3a9/0x1390 [ubifs] ubifs_change_one_lp+0x170/0x220 [ubifs] ubifs_garbage_collect+0x7f9/0xda0 [ubifs] ubifs_budget_space+0xfe4/0x1bd0 [ubifs] ubifs_write_begin+0x528/0x10c0 [ubifs] Allocated by task 1068: kmemdup+0x25/0x50 ubifs_lpt_lookup_dirty+0x372/0xb00 [ubifs] ubifs_update_one_lp+0x46/0x260 [ubifs] ubifs_tnc_end_commit+0x98b/0x1720 [ubifs] do_commit+0x6cb/0x1950 [ubifs] ubifs_run_commit+0x15a/0x2b0 [ubifs] ubifs_budget_space+0x1061/0x1bd0 [ubifs] ubifs_write_begin+0x528/0x10c0 [ubifs] [...] ================================================================== In ubifs_garbage_collect(), if ubifs_find_dirty_leb returns an error, lp is an uninitialized variable. But lp.num might be used in the out branch, which is a random value. If the value is -1 or another value that can pass the check, soob may occur in the ubifs_change_lp() in the following procedure. To solve this problem, we initialize lp.lnum to -1, and then initialize it correctly in ubifs_find_dirty_leb, which is not equal to -1, and ubifs_return_leb is executed only when lp.lnum != -1. if find a retained or indexing LEB and continue to next loop, but break before find another LEB, the "taken" flag of this LEB will be cleaned in ubi_return_lebi(). This bug has also been fixed in this patch. Reported-by:
Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Dan Carpenter authored
The snprintf() function returns the number of bytes (not including the NUL terminator) which would have been printed if there were enough space. So it can be greater than UBIFS_DFS_DIR_LEN. And actually if it equals UBIFS_DFS_DIR_LEN then that's okay so this check is too strict. Fixes: 9a620291fc01 ("ubifs: Export filesystem error counters") Signed-off-by:Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Stefan Schaeckeler authored
Add documentation for the new sysfs nodes /sys/fs/ubifs/ubiX_Y/errors_magic /sys/fs/ubifs/ubiX_Y/errors_node /sys/fs/ubifs/ubiX_Y/errors_crc Signed-off-by:
Stefan Schaeckeler <sschaeck@cisco.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Stefan Schaeckeler authored
Not all ubifs filesystem errors are propagated to userspace. Export bad magic, bad node and crc errors via sysfs. This allows userspace to notice filesystem errors: /sys/fs/ubifs/ubiX_Y/errors_magic /sys/fs/ubifs/ubiX_Y/errors_node /sys/fs/ubifs/ubiX_Y/errors_crc The counters are reset to 0 with a remount. Signed-off-by:
Stefan Schaeckeler <sschaeck@cisco.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Petr Cvachoucek authored
it seems freeing the write buffers in the error path of the ubifs_remount_rw() is wrong. It leads later to a kernel oops like this: [10016.431274] UBIFS (ubi0:0): start fixing up free space [10090.810042] UBIFS (ubi0:0): free space fixup complete [10090.814623] UBIFS error (ubi0:0 pid 512): ubifs_remount_fs: cannot spawn "ubifs_bgt0_0", error -4 [10101.915108] UBIFS (ubi0:0): background thread "ubifs_bgt0_0" started, PID 517 [10105.275498] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000030 [10105.284352] Mem abort info: [10105.287160] ESR = 0x96000006 [10105.290252] EC = 0x25: DABT (current EL), IL = 32 bits [10105.295592] SET = 0, FnV = 0 [10105.298652] EA = 0, S1PTW = 0 [10105.301848] Data abort info: [10105.304723] ISV = 0, ISS = 0x00000006 [10105.308573] CM = 0, WnR = 0 [10105.311564] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000f03d1000 [10105.318034] [0000000000000030] pgd=00000000f6cee003, pud=00000000f4884003, pmd=0000000000000000 [10105.326783] Internal error: Oops: 96000006 [#1] PREEMPT SMP [10105.332355] Modules linked in: ath10k_pci ath10k_core ath mac80211 libarc4 cfg80211 nvme nvme_core cryptodev(O) [10105.342468] CPU: 3 PID: 518 Comm: touch Tainted: G O 5.4.3 #1 [10105.349517] Hardware name: HYPEX CPU (DT) [10105.353525] pstate: 40000005 (nZcv daif -PAN -UAO) [10105.358324] pc : atomic64_try_cmpxchg_acquire.constprop.22+0x8/0x34 [10105.364596] lr : mutex_lock+0x1c/0x34 [10105.368253] sp : ffff000075633aa0 [10105.371563] x29: ffff000075633aa0 x28: 0000000000000001 [10105.376874] x27: ffff000076fa80c8 x26: 0000000000000004 [10105.382185] x25: 0000000000000030 x24: 0000000000000000 [10105.387495] x23: 0000000000000000 x22: 0000000000000038 [10105.392807] x21: 000000000000000c x20: ffff000076fa80c8 [10105.398119] x19: ffff000076fa8000 x18: 0000000000000000 [10105.403429] x17: 0000000000000000 x16: 0000000000000000 [10105.408741] x15: 0000000000000000 x14: fefefefefefefeff [10105.414052] x13: 0000000000000000 x12: 0000000000000fe0 [10105.419364] x11: 0000000000000fe0 x10: ffff000076709020 [10105.424675] x9 : 0000000000000000 x8 : 00000000000000a0 [10105.429986] x7 : ffff000076fa80f4 x6 : 0000000000000030 [10105.435297] x5 : 0000000000000000 x4 : 0000000000000000 [10105.440609] x3 : 0000000000000000 x2 : ffff00006f276040 [10105.445920] x1 : ffff000075633ab8 x0 : 0000000000000030 [10105.451232] Call trace: [10105.453676] atomic64_try_cmpxchg_acquire.constprop.22+0x8/0x34 [10105.459600] ubifs_garbage_collect+0xb4/0x334 [10105.463956] ubifs_budget_space+0x398/0x458 [10105.468139] ubifs_create+0x50/0x180 [10105.471712] path_openat+0x6a0/0x9b0 [10105.475284] do_filp_open+0x34/0x7c [10105.478771] do_sys_open+0x78/0xe4 [10105.482170] __arm64_sys_openat+0x1c/0x24 [10105.486180] el0_svc_handler+0x84/0xc8 [10105.489928] el0_svc+0x8/0xc [10105.492808] Code: 52800013 17fffffb d2800003 f9800011 (c85ffc05) [10105.498903] ---[ end trace 46b721d93267a586 ]--- To reproduce the problem: 1. Filesystem initially mounted read-only, free space fixup flag set. 2. mount -o remount,rw <mountpoint> 3. it takes some time (free space fixup running) ... try to terminate running mount by CTRL-C ... does not respond, only after free space fixup is complete ... then "ubifs_remount_fs: cannot spawn "ubifs_bgt0_0", error -4" 4. mount -o remount,rw <mountpoint> ... now finished instantly (fixup already done). 5. Create file or just unmount the filesystem and we get the oops. Cc: <stable@vger.kernel.org> Fixes: b50b9f40 ("UBIFS: do not free write-buffers when in R/O mode") Signed-off-by:
Petr Cvachoucek <cvachoucek@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Cai Huoqing authored
Repalce kthread_create/wake_up_process() with kthread_run() to simplify the code. Signed-off-by:
Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Kai Song authored
Fixes: 2a734bb8 ("UBI: use debugfs for the extra checks knobs") There is a mistake in docstrings, it should be ubi_debugfs_exit_dev instead of dbg_debug_exit_dev. Signed-off-by:
Kai Song <songkai01@inspur.com>
Signed-off-by: Richard Weinberger <richard@nod.at> -
Alexander Dahl authored
Found with `codespell -i 3 -w fs/ubifs/**` and proof reading that parts. Signed-off-by:
Alexander Dahl <ada@thorsis.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
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- Dec 20, 2021
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull kvm fixes from Paolo Bonzini: "Two small fixes, one of which was being worked around in selftests" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Retry page fault if MMU reload is pending and root has no sp KVM: selftests: vmx_pmu_msrs_test: Drop tests mangling guest visible CPUIDs KVM: x86: Drop guest CPUID check for host initiated writes to MSR_IA32_PERF_CAPABILITIES
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block revert from Jens Axboe: "It turns out that the fix for not hammering on the delayed work timer too much caused a performance regression for BFQ, so let's revert the change for now. I've got some ideas on how to fix it appropriately, but they should wait for 5.17" * tag 'block-5.16-2021-12-19' of git://git.kernel.dk/linux-block: Revert "block: reduce kblockd_mod_delayed_work_on() CPU consumption"
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull irq fixes from Borislav Petkov: - Clear the PCI_MSIX_FLAGS_MASKALL bit too on the error path so that it is restored to its reset state - Mask MSI-X vectors late on the init path in order to handle out-of-spec Marvell NVME devices which apparently look at the MSI-X mask even when MSI-X is disabled * tag 'irq_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error PCI/MSI: Mask MSI-X vectors only on success
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fix from Borislav Petkov: - Make sure the CLOCK_REALTIME to CLOCK_MONOTONIC offset is never positive * tag 'timers_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Really make sure wall_to_monotonic isn't positive
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull locking fix from Borislav Petkov: - Fix the rtmutex condition checking when the optimistic spinning of a waiter needs to be terminated * tag 'locking_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rtmutex: Fix incorrect condition in rtmutex_spin_on_owner()
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull signal handlign fix from Borislav Petkov: - Prevent lock contention on the new sigaltstack lock on the common-case path, when no changes have been made to the alternative signal stack. * tag 'core_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: signal: Skip the altstack update when not needed
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git://git.kernel.org/pub/scm/linux/kernel/git/mips/linuxLinus Torvalds authored
Pull MIPS fix from Thomas Bogendoerfer: - only enable pci_remap_iospace() for Ralink devices * tag 'mips-fixes_5.16_3' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: MIPS: Only define pci_remap_iospace() for Ralink
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: "Fix a recently introduced oops at boot on 85xx in some configurations. Fix crashes when loading some livepatch modules with STRICT_MODULE_RWX. Thanks to Joe Lawrence, Russell Currey, and Xiaoming Ni" * tag 'powerpc-5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/module_64: Fix livepatching for RO modules powerpc/85xx: Fix oops when CONFIG_FSL_PMC=n
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull cifs fixes from Steve French: "Two cifs/smb3 fixes, one fscache related, and one mount parsing related for stable" * tag '5.16-rc5-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: sanitize multiple delimiters in prepath cifs: ignore resource_id while getting fscache super cookie
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Sean Christopherson authored
Play nice with a NULL shadow page when checking for an obsolete root in the page fault handler by flagging the page fault as stale if there's no shadow page associated with the root and KVM_REQ_MMU_RELOAD is pending. Invalidating memslots, which is the only case where _all_ roots need to be reloaded, requests all vCPUs to reload their MMUs while holding mmu_lock for lock. The "special" roots, e.g. pae_root when KVM uses PAE paging, are not backed by a shadow page. Running with TDP disabled or with nested NPT explodes spectaculary due to dereferencing a NULL shadow page pointer. Skip the KVM_REQ_MMU_RELOAD check if there is a valid shadow page for the root. Zapping shadow pages in response to guest activity, e.g. when the guest frees a PGD, can trigger KVM_REQ_MMU_RELOAD even if the current vCPU isn't using the affected root. I.e. KVM_REQ_MMU_RELOAD can be seen with a completely valid root shadow page. This is a bit of a moot point as KVM currently unloads all roots on KVM_REQ_MMU_RELOAD, but that will be cleaned up in the future. Fixes: a955cad8 ("KVM: x86/mmu: Retry page fault if root is invalidated by memslot update") Cc: stable@vger.kernel.org Cc: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by:
Sean Christopherson <seanjc@google.com>
Message-Id: <20211209060552.2956723-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> -
Vitaly Kuznetsov authored
Host initiated writes to MSR_IA32_PERF_CAPABILITIES should not depend on guest visible CPUIDs and (incorrect) KVM logic implementing it is about to change. Also, KVM_SET_CPUID{,2} after KVM_RUN is now forbidden and causes test to fail. Reported-by:kernel test robot <oliver.sang@intel.com>
Fixes: feb627e8
("KVM: x86: Forbid KVM_SET_CPUID{,2} after KVM_RUN")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211216165213.338923-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> -
Vitaly Kuznetsov authored
The ability to write to MSR_IA32_PERF_CAPABILITIES from the host should not depend on guest visible CPUID entries, even if just to allow creating/restoring guest MSRs and CPUIDs in any sequence. Fixes: 27461da3 ("KVM: x86/pmu: Support full width counting") Suggested-by:
Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211216165213.338923-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- Dec 19, 2021
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Jens Axboe authored
This reverts commit cb2ac291. Alex and the kernel test robot report that this causes a significant performance regression with BFQ. I can reproduce that result, so let's revert this one as we're close to -rc6 and we there's no point in trying to rush a fix. Link: https://lore.kernel.org/linux-block/1639853092.524jxfaem2.none@localhost/ Link: https://lore.kernel.org/lkml/20211219141852.GH14057@xsang-OptiPlex-9020/ Reported-by:
Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk> -
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/ttyLinus Torvalds authored
Pull tty/serial fixes from Greg KH: "Here are two small tty/serial fixes for 5.16-rc6. They include: - n_hdlc fix for syzbot reported problem that you were previously copied on. - 8250_fintek driver fix that resolved a console problem by removing a previous change. Both have been in linux-next with no reported issues" * tag 'tty-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: serial: 8250_fintek: Fix garbled text for console tty: n_hdlc: make n_hdlc_tty_wakeup() asynchronous -
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usbLinus Torvalds authored
Pull USB fixes from Greg KH: "Here are a number of small USB driver fixes for reported problems. They include: - dwc2 driver fixes - xhci driver fixes - cdnsp driver fixes - typec driver fix - gadget u_ether driver fix - new quirk additions - usb gadget endpoint calculation fix - usb serial new device ids - revert of a xhci-dbg change that broke early debug booting All changes, except for the revert, have been in linux-next with no reported problems. The revert was from yesterday, and it was reported by the developers affected that it resolved their problem" * tag 'usb-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: Revert "usb: early: convert to readl_poll_timeout_atomic()" usb: typec: tcpm: fix tcpm unregister port but leave a pending timer usb: cdnsp: Fix lack of spin_lock_irqsave/spin_lock_restore USB: NO_LPM quirk Lenovo USB-C to Ethernet Adapher(RTL8153-04) usb: xhci: Extend support for runtime power management for AMD's Yellow carp. usb: dwc2: fix STM ID/VBUS detection startup delay in dwc2_driver_probe USB: gadget: bRequestType is a bitfield, not a enum USB: serial: option: add Telit FN990 compositions USB: serial: cp210x: fix CP2105 GPIO registration usb: cdnsp: Fix incorrect status for control request usb: cdnsp: Fix issue in cdnsp_log_ep trace event usb: cdnsp: Fix incorrect calling of cdnsp_died function usb: xhci-mtk: fix list_del warning when enable list debug usb: gadget: u_ether: fix race in setting MAC address in setup phase
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Linus Torvalds authored
Merge tag 'perf-tools-fixes-for-v5.16-2021-12-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux Pull perf tools fixes from Arnaldo Carvalho de Melo: - Fix segfaults in 'perf inject' related to usage of unopened files - The return value of hashmap__new() should be checked using IS_ERR() * tag 'perf-tools-fixes-for-v5.16-2021-12-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: perf inject: Fix segfault due to perf_data__fd() without open perf inject: Fix segfault due to close without open perf expr: Fix missing check for return value of hashmap__new()
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- Dec 18, 2021
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Adrian Hunter authored
The fixed commit attempts to get the output file descriptor even if the file was never opened e.g. $ perf record uname Linux [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.002 MB perf.data (7 samples) ] $ perf inject -i perf.data --vm-time-correlation=dry-run Segmentation fault (core dumped) $ gdb --quiet perf Reading symbols from perf... (gdb) r inject -i perf.data --vm-time-correlation=dry-run Starting program: /home/ahunter/bin/perf inject -i perf.data --vm-time-correlation=dry-run [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. __GI___fileno (fp=0x0) at fileno.c:35 35 fileno.c: No such file or directory. (gdb) bt #0 __GI___fileno (fp=0x0) at fileno.c:35 #1 0x00005621e48dd987 in perf_data__fd (data=0x7fff4c68bd08) at util/data.h:72 #2 perf_data__fd (data=0x7fff4c68bd08) at util/data.h:69 #3 cmd_inject (argc=<optimized out>, argv=0x7fff4c69c1f0) at builtin-inject.c:1017 #4 0x00005621e4936783 in run_builtin (p=0x5621e4ee6878 <commands+600>, argc=4, argv=0x7fff4c69c1f0) at perf.c:313 #5 0x00005621e4897d5c in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:365 #6 run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:409 #7 main (argc=4, argv=0x7fff4c69c1f0) at perf.c:539 (gdb) Fixes: 0ae03893 ("perf tools: Pass a fd to perf_file_header__read_pipe()") Signed-off-by:
Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211213084829.114772-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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