c576c4bf9e
In journal_init_dev(), if super bdev is used as 'j_dev_bd', then blkdev_get_by_dev() is called with NULL holder, otherwise, holder will be journal. However, later in release_journal_dev(), blkdev_put() is called with journal unconditionally, cause following warning: WARNING: CPU: 1 PID: 5034 at block/bdev.c:617 bd_end_claim block/bdev.c:617 [inline] WARNING: CPU: 1 PID: 5034 at block/bdev.c:617 blkdev_put+0x562/0x8a0 block/bdev.c:901 RIP: 0010:blkdev_put+0x562/0x8a0 block/bdev.c:901 Call Trace: <TASK> release_journal_dev fs/reiserfs/journal.c:2592 [inline] free_journal_ram+0x421/0x5c0 fs/reiserfs/journal.c:1896 do_journal_release fs/reiserfs/journal.c:1960 [inline] journal_release+0x276/0x630 fs/reiserfs/journal.c:1971 reiserfs_put_super+0xe4/0x5c0 fs/reiserfs/super.c:616 generic_shutdown_super+0x158/0x480 fs/super.c:499 kill_block_super+0x64/0xb0 fs/super.c:1422 deactivate_locked_super+0x98/0x160 fs/super.c:330 deactivate_super+0xb1/0xd0 fs/super.c:361 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1247 task_work_run+0x16f/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xadc/0x2a30 kernel/exit.c:874 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fix this problem by passing in NULL holder in this case. Reported-by: syzbot+04625c80899f4555de39@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=04625c80899f4555de39 Fixes: 2736e8eeb0cc ("block: use the holder as indication for exclusive opens") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230620111322.1014775-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.