| From a09ac81cf8284c9df91d9614863e3f5c5b1e00dd Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Wed, 13 Oct 2021 20:19:14 +0800 |
| Subject: PM: hibernate: Get block device exclusively in swsusp_check() |
| |
| From: Ye Bin <yebin10@huawei.com> |
| |
| [ Upstream commit 39fbef4b0f77f9c89c8f014749ca533643a37c9f ] |
| |
| The following kernel crash can be triggered: |
| |
| [ 89.266592] ------------[ cut here ]------------ |
| [ 89.267427] kernel BUG at fs/buffer.c:3020! |
| [ 89.268264] invalid opcode: 0000 [#1] SMP KASAN PTI |
| [ 89.269116] CPU: 7 PID: 1750 Comm: kmmpd-loop0 Not tainted 5.10.0-862.14.0.6.x86_64-08610-gc932cda3cef4-dirty #20 |
| [ 89.273169] RIP: 0010:submit_bh_wbc.isra.0+0x538/0x6d0 |
| [ 89.277157] RSP: 0018:ffff888105ddfd08 EFLAGS: 00010246 |
| [ 89.278093] RAX: 0000000000000005 RBX: ffff888124231498 RCX: ffffffffb2772612 |
| [ 89.279332] RDX: 1ffff11024846293 RSI: 0000000000000008 RDI: ffff888124231498 |
| [ 89.280591] RBP: ffff8881248cc000 R08: 0000000000000001 R09: ffffed1024846294 |
| [ 89.281851] R10: ffff88812423149f R11: ffffed1024846293 R12: 0000000000003800 |
| [ 89.283095] R13: 0000000000000001 R14: 0000000000000000 R15: ffff8881161f7000 |
| [ 89.284342] FS: 0000000000000000(0000) GS:ffff88839b5c0000(0000) knlGS:0000000000000000 |
| [ 89.285711] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| [ 89.286701] CR2: 00007f166ebc01a0 CR3: 0000000435c0e000 CR4: 00000000000006e0 |
| [ 89.287919] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 |
| [ 89.289138] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 |
| [ 89.290368] Call Trace: |
| [ 89.290842] write_mmp_block+0x2ca/0x510 |
| [ 89.292218] kmmpd+0x433/0x9a0 |
| [ 89.294902] kthread+0x2dd/0x3e0 |
| [ 89.296268] ret_from_fork+0x22/0x30 |
| [ 89.296906] Modules linked in: |
| |
| by running the following commands: |
| |
| 1. mkfs.ext4 -O mmp /dev/sda -b 1024 |
| 2. mount /dev/sda /home/test |
| 3. echo "/dev/sda" > /sys/power/resume |
| |
| That happens because swsusp_check() calls set_blocksize() on the |
| target partition which confuses the file system: |
| |
| Thread1 Thread2 |
| mount /dev/sda /home/test |
| get s_mmp_bh --> has mapped flag |
| start kmmpd thread |
| echo "/dev/sda" > /sys/power/resume |
| resume_store |
| software_resume |
| swsusp_check |
| set_blocksize |
| truncate_inode_pages_range |
| truncate_cleanup_page |
| block_invalidatepage |
| discard_buffer --> clean mapped flag |
| write_mmp_block |
| submit_bh |
| submit_bh_wbc |
| BUG_ON(!buffer_mapped(bh)) |
| |
| To address this issue, modify swsusp_check() to open the target block |
| device with exclusive access. |
| |
| Signed-off-by: Ye Bin <yebin10@huawei.com> |
| [ rjw: Subject and changelog edits ] |
| Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| kernel/power/swap.c | 5 +++-- |
| 1 file changed, 3 insertions(+), 2 deletions(-) |
| |
| diff --git a/kernel/power/swap.c b/kernel/power/swap.c |
| index 0516c422206d8..d32cd03d5ff8c 100644 |
| --- a/kernel/power/swap.c |
| +++ b/kernel/power/swap.c |
| @@ -1509,9 +1509,10 @@ end: |
| int swsusp_check(void) |
| { |
| int error; |
| + void *holder; |
| |
| hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, |
| - FMODE_READ, NULL); |
| + FMODE_READ | FMODE_EXCL, &holder); |
| if (!IS_ERR(hib_resume_bdev)) { |
| set_blocksize(hib_resume_bdev, PAGE_SIZE); |
| clear_page(swsusp_header); |
| @@ -1533,7 +1534,7 @@ int swsusp_check(void) |
| |
| put: |
| if (error) |
| - blkdev_put(hib_resume_bdev, FMODE_READ); |
| + blkdev_put(hib_resume_bdev, FMODE_READ | FMODE_EXCL); |
| else |
| pr_debug("Image signature found, resuming\n"); |
| } else { |
| -- |
| 2.33.0 |
| |