60eb3b9c9f
'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:
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
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.