Re: [PATCH 2/2] f2fs: fix to do sanity check with inline flags
From: Jaegeuk Kim
Date: Fri Jul 06 2018 - 21:13:02 EST
Hi Chao,
I'm hitting some messages below during fault injection test. I'll dig in the
issue later, but meanwhile could you review this patch again?
Thanks,
On 06/28, Chao Yu wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=200221
>
> - Overview
> BUG() in clear_inode() when mounting and un-mounting a corrupted f2fs image
>
> - Reproduce
>
> - Kernel message
> [ 538.601448] F2FS-fs (loop0): Invalid segment/section count (31, 24 x 1376257)
> [ 538.601458] F2FS-fs (loop0): Can't find valid F2FS filesystem in 2th superblock
> [ 538.724091] F2FS-fs (loop0): Try to recover 2th superblock, ret: 0
> [ 538.724102] F2FS-fs (loop0): Mounted with checkpoint version = 2
> [ 540.970834] ------------[ cut here ]------------
> [ 540.970838] kernel BUG at fs/inode.c:512!
> [ 540.971750] invalid opcode: 0000 [#1] SMP KASAN PTI
> [ 540.972755] CPU: 1 PID: 1305 Comm: umount Not tainted 4.18.0-rc1+ #4
> [ 540.974034] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> [ 540.982913] RIP: 0010:clear_inode+0xc0/0xd0
> [ 540.983774] Code: 8d a3 30 01 00 00 4c 89 e7 e8 1c ec f8 ff 48 8b 83 30 01 00 00 49 39 c4 75 1a 48 c7 83 a0 00 00 00 60 00 00 00 5b 41 5c 5d c3 <0f> 0b 0f 0b 0f 0b 0f 0b 0f 0b 0f 0b 0f 1f 40 00 66 66 66 66 90 55
> [ 540.987570] RSP: 0018:ffff8801e34a7b70 EFLAGS: 00010002
> [ 540.988636] RAX: 0000000000000000 RBX: ffff8801e9b744e8 RCX: ffffffffb840eb3a
> [ 540.990063] RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff8801e9b746b8
> [ 540.991499] RBP: ffff8801e34a7b80 R08: ffffed003d36e8ce R09: ffffed003d36e8ce
> [ 540.992923] R10: 0000000000000001 R11: ffffed003d36e8cd R12: ffff8801e9b74668
> [ 540.994360] R13: ffff8801e9b74760 R14: ffff8801e9b74528 R15: ffff8801e9b74530
> [ 540.995786] FS: 00007f4662bdf840(0000) GS:ffff8801f6f00000(0000) knlGS:0000000000000000
> [ 540.997403] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 540.998571] CR2: 000000000175c568 CR3: 00000001dcfe6000 CR4: 00000000000006e0
> [ 541.000015] Call Trace:
> [ 541.000554] f2fs_evict_inode+0x253/0x630
> [ 541.001381] evict+0x16f/0x290
> [ 541.002015] iput+0x280/0x300
> [ 541.002654] dentry_unlink_inode+0x165/0x1e0
> [ 541.003528] __dentry_kill+0x16a/0x260
> [ 541.004300] dentry_kill+0x70/0x250
> [ 541.005018] dput+0x154/0x1d0
> [ 541.005635] do_one_tree+0x34/0x40
> [ 541.006354] shrink_dcache_for_umount+0x3f/0xa0
> [ 541.007285] generic_shutdown_super+0x43/0x1c0
> [ 541.008192] kill_block_super+0x52/0x80
> [ 541.008978] kill_f2fs_super+0x62/0x70
> [ 541.009750] deactivate_locked_super+0x6f/0xa0
> [ 541.010664] deactivate_super+0x5e/0x80
> [ 541.011450] cleanup_mnt+0x61/0xa0
> [ 541.012151] __cleanup_mnt+0x12/0x20
> [ 541.012893] task_work_run+0xc8/0xf0
> [ 541.013635] exit_to_usermode_loop+0x125/0x130
> [ 541.014555] do_syscall_64+0x138/0x170
> [ 541.015340] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [ 541.016375] RIP: 0033:0x7f46624bf487
> [ 541.017104] Code: 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 c9 2b 00 f7 d8 64 89 01 48
> [ 541.020923] RSP: 002b:00007fff5e12e9a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
> [ 541.022452] RAX: 0000000000000000 RBX: 0000000001753030 RCX: 00007f46624bf487
> [ 541.023885] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000175a1e0
> [ 541.025318] RBP: 000000000175a1e0 R08: 0000000000000000 R09: 0000000000000014
> [ 541.026755] R10: 00000000000006b2 R11: 0000000000000246 R12: 00007f46629c883c
> [ 541.028186] R13: 0000000000000000 R14: 0000000001753210 R15: 00007fff5e12ec30
> [ 541.029626] Modules linked in: snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_pcm snd_timer snd mac_hid i2c_piix4 soundcore ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx raid1 raid0 multipath linear 8139too crct10dif_pclmul crc32_pclmul qxl drm_kms_helper syscopyarea aesni_intel sysfillrect sysimgblt fb_sys_fops ttm drm aes_x86_64 crypto_simd cryptd 8139cp glue_helper mii pata_acpi floppy
> [ 541.039445] ---[ end trace 4ce02f25ff7d3df5 ]---
> [ 541.040392] RIP: 0010:clear_inode+0xc0/0xd0
> [ 541.041240] Code: 8d a3 30 01 00 00 4c 89 e7 e8 1c ec f8 ff 48 8b 83 30 01 00 00 49 39 c4 75 1a 48 c7 83 a0 00 00 00 60 00 00 00 5b 41 5c 5d c3 <0f> 0b 0f 0b 0f 0b 0f 0b 0f 0b 0f 0b 0f 1f 40 00 66 66 66 66 90 55
> [ 541.045042] RSP: 0018:ffff8801e34a7b70 EFLAGS: 00010002
> [ 541.046099] RAX: 0000000000000000 RBX: ffff8801e9b744e8 RCX: ffffffffb840eb3a
> [ 541.047537] RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff8801e9b746b8
> [ 541.048965] RBP: ffff8801e34a7b80 R08: ffffed003d36e8ce R09: ffffed003d36e8ce
> [ 541.050402] R10: 0000000000000001 R11: ffffed003d36e8cd R12: ffff8801e9b74668
> [ 541.051832] R13: ffff8801e9b74760 R14: ffff8801e9b74528 R15: ffff8801e9b74530
> [ 541.053263] FS: 00007f4662bdf840(0000) GS:ffff8801f6f00000(0000) knlGS:0000000000000000
> [ 541.054891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 541.056039] CR2: 000000000175c568 CR3: 00000001dcfe6000 CR4: 00000000000006e0
> [ 541.058506] ==================================================================
> [ 541.059991] BUG: KASAN: stack-out-of-bounds in update_stack_state+0x38c/0x3e0
> [ 541.061513] Read of size 8 at addr ffff8801e34a7970 by task umount/1305
>
> [ 541.063302] CPU: 1 PID: 1305 Comm: umount Tainted: G D 4.18.0-rc1+ #4
> [ 541.064838] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
> [ 541.066778] Call Trace:
> [ 541.067294] dump_stack+0x7b/0xb5
> [ 541.067986] print_address_description+0x70/0x290
> [ 541.068941] kasan_report+0x291/0x390
> [ 541.069692] ? update_stack_state+0x38c/0x3e0
> [ 541.070598] __asan_load8+0x54/0x90
> [ 541.071315] update_stack_state+0x38c/0x3e0
> [ 541.072172] ? __read_once_size_nocheck.constprop.7+0x20/0x20
> [ 541.073340] ? vprintk_func+0x27/0x60
> [ 541.074096] ? printk+0xa3/0xd3
> [ 541.074762] ? __save_stack_trace+0x5e/0x100
> [ 541.075634] unwind_next_frame.part.5+0x18e/0x490
> [ 541.076594] ? unwind_dump+0x290/0x290
> [ 541.077368] ? __show_regs+0x2c4/0x330
> [ 541.078142] __unwind_start+0x106/0x190
> [ 541.085422] __save_stack_trace+0x5e/0x100
> [ 541.086268] ? __save_stack_trace+0x5e/0x100
> [ 541.087161] ? unlink_anon_vmas+0xba/0x2c0
> [ 541.087997] save_stack_trace+0x1f/0x30
> [ 541.088782] save_stack+0x46/0xd0
> [ 541.089475] ? __alloc_pages_slowpath+0x1420/0x1420
> [ 541.090477] ? flush_tlb_mm_range+0x15e/0x220
> [ 541.091364] ? __dec_node_state+0x24/0xb0
> [ 541.092180] ? lock_page_memcg+0x85/0xf0
> [ 541.092979] ? unlock_page_memcg+0x16/0x80
> [ 541.093812] ? page_remove_rmap+0x198/0x520
> [ 541.094674] ? mark_page_accessed+0x133/0x200
> [ 541.095559] ? _cond_resched+0x1a/0x50
> [ 541.096326] ? unmap_page_range+0xcd4/0xe50
> [ 541.097179] ? rb_next+0x58/0x80
> [ 541.097845] ? rb_next+0x58/0x80
> [ 541.098518] __kasan_slab_free+0x13c/0x1a0
> [ 541.099352] ? unlink_anon_vmas+0xba/0x2c0
> [ 541.100184] kasan_slab_free+0xe/0x10
> [ 541.100934] kmem_cache_free+0x89/0x1e0
> [ 541.101724] unlink_anon_vmas+0xba/0x2c0
> [ 541.102534] free_pgtables+0x101/0x1b0
> [ 541.103299] exit_mmap+0x146/0x2a0
> [ 541.103996] ? __ia32_sys_munmap+0x50/0x50
> [ 541.104829] ? kasan_check_read+0x11/0x20
> [ 541.105649] ? mm_update_next_owner+0x322/0x380
> [ 541.106578] mmput+0x8b/0x1d0
> [ 541.107191] do_exit+0x43a/0x1390
> [ 541.107876] ? mm_update_next_owner+0x380/0x380
> [ 541.108791] ? deactivate_super+0x5e/0x80
> [ 541.109610] ? cleanup_mnt+0x61/0xa0
> [ 541.110351] ? __cleanup_mnt+0x12/0x20
> [ 541.111115] ? task_work_run+0xc8/0xf0
> [ 541.111879] ? exit_to_usermode_loop+0x125/0x130
> [ 541.112817] rewind_stack_do_exit+0x17/0x20
> [ 541.113666] RIP: 0033:0x7f46624bf487
> [ 541.114404] Code: Bad RIP value.
> [ 541.115094] RSP: 002b:00007fff5e12e9a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
> [ 541.116605] RAX: 0000000000000000 RBX: 0000000001753030 RCX: 00007f46624bf487
> [ 541.118034] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000175a1e0
> [ 541.119472] RBP: 000000000175a1e0 R08: 0000000000000000 R09: 0000000000000014
> [ 541.120890] R10: 00000000000006b2 R11: 0000000000000246 R12: 00007f46629c883c
> [ 541.122321] R13: 0000000000000000 R14: 0000000001753210 R15: 00007fff5e12ec30
>
> [ 541.124061] The buggy address belongs to the page:
> [ 541.125042] page:ffffea00078d29c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
> [ 541.126651] flags: 0x2ffff0000000000()
> [ 541.127418] raw: 02ffff0000000000 dead000000000100 dead000000000200 0000000000000000
> [ 541.128963] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
> [ 541.130516] page dumped because: kasan: bad access detected
>
> [ 541.131954] Memory state around the buggy address:
> [ 541.132924] ffff8801e34a7800: 00 f1 f1 f1 f1 00 f4 f4 f4 f3 f3 f3 f3 00 00 00
> [ 541.134378] ffff8801e34a7880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> [ 541.135814] >ffff8801e34a7900: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
> [ 541.137253] ^
> [ 541.138637] ffff8801e34a7980: f1 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> [ 541.140075] ffff8801e34a7a00: 00 00 00 00 00 00 00 00 f3 00 00 00 00 00 00 00
> [ 541.141509] ==================================================================
>
> - Location
> https://elixir.bootlin.com/linux/v4.18-rc1/source/fs/inode.c#L512
> BUG_ON(inode->i_data.nrpages);
>
> The root cause is root directory inode is corrupted, it has both
> inline_data and inline_dentry flag, and its nlink is zero, so in
> ->evict(), after dropping all page cache, it grabs page #0 for inline
> data truncation, result in panic in later clear_inode() where we will
> check inode->i_data.nrpages value.
>
> This patch adds inline flags check in sanity_check_inode, in addition,
> do sanity check with root inode's nlink.
>
> Reported-by Wen Xu <wen.xu@xxxxxxxxxx>
> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> ---
> fs/f2fs/inode.c | 20 ++++++++++++++++++++
> fs/f2fs/super.c | 3 ++-
> 2 files changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
> index 54067e456610..4cf0a05cc03e 100644
> --- a/fs/f2fs/inode.c
> +++ b/fs/f2fs/inode.c
> @@ -224,6 +224,26 @@ static bool sanity_check_inode(struct inode *inode)
> return false;
> }
> }
> +
> + if (f2fs_has_inline_data(inode) &&
> + (!S_ISREG(inode->i_mode) || !S_ISLNK(inode->i_mode))) {
> + set_sbi_flag(sbi, SBI_NEED_FSCK);
> + f2fs_msg(sbi->sb, KERN_WARNING,
> + "%s: inode (ino=%lx, mode=%u) should not have "
> + "inline_data, run fsck to fix",
> + __func__, inode->i_ino, inode->i_mode);
> + return false;
> + }
> +
> + if (f2fs_has_inline_dentry(inode) && !S_ISDIR(inode->i_mode)) {
> + set_sbi_flag(sbi, SBI_NEED_FSCK);
> + f2fs_msg(sbi->sb, KERN_WARNING,
> + "%s: inode (ino=%lx, mode=%u) should not have "
> + "inline_dentry, run fsck to fix",
> + __func__, inode->i_ino, inode->i_mode);
> + return false;
> + }
> +
> return true;
> }
>
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 657757635306..7405762d2bc9 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -2942,7 +2942,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
> err = PTR_ERR(root);
> goto free_stats;
> }
> - if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
> + if (!S_ISDIR(root->i_mode) || !root->i_blocks ||
> + !root->i_size || !root->i_nlink) {
> iput(root);
> err = -EINVAL;
> goto free_stats;
> --
> 2.18.0.rc1