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ZhengYuan Huang 738ce4979c ocfs2: reject inconsistent inode size before truncate
[BUG]
openat(..., O_WRONLY|O_CREAT|O_TRUNC) can hit:

kernel BUG at fs/ocfs2/file.c:454!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:ocfs2_truncate_file+0x1204/0x13c0 fs/ocfs2/file.c:454
Call Trace:
 ocfs2_setattr+0xa6d/0x1fd0 fs/ocfs2/file.c:1212
 notify_change+0x4b5/0x1030 fs/attr.c:546
 do_truncate+0x1d2/0x230 fs/open.c:68
 handle_truncate fs/namei.c:3596 [inline]
 do_open fs/namei.c:3979 [inline]
 path_openat+0x260f/0x2ce0 fs/namei.c:4134
 do_filp_open+0x1f6/0x430 fs/namei.c:4161
 do_sys_openat2+0x117/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x15b/0x220 fs/open.c:1463
 ...

[CAUSE]
ocfs2_truncate_file() treats di_bh->i_size matching inode->i_size as an
internal code invariant and BUGs if it is broken.

That assumption is too strong for corrupted metadata. The dinode block can
still be structurally valid enough to pass ocfs2_read_inode_block() while
no longer matching an already-instantiated VFS inode. On local mounts,
ocfs2_inode_lock_update() skips refresh entirely, so truncate can
observe the mismatch directly and crash instead of rejecting the
corruption.

[FIX]
Turn the BUG_ON into normal OCFS2 corruption handling. If truncate sees
di_bh->i_size disagree with inode->i_size, report it with ocfs2_error() and
abort before touching truncate state.

This keeps the fix at the first boundary that actually requires the
sizes to match and avoids widening checks into hotter generic
inode-lock paths

Link: https://lore.kernel.org/20260512021601.3936417-1-gality369@gmail.com
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28 21:24:47 -07:00
arch uaccess: unify inline vs outline copy_{from,to}_user() selection 2026-05-28 21:24:44 -07:00
block cgroup: Fixes for v7.1-rc4 2026-05-22 16:28:47 -07:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks 2026-05-20 16:36:45 -07:00
Documentation checkpatch: add option to not force /* */ for SPDX 2026-05-28 21:24:39 -07:00
drivers rapidio/tsi721: prevent a bad dereference in tsi721_db_dpc() 2026-05-28 21:24:45 -07:00
fs ocfs2: reject inconsistent inode size before truncate 2026-05-28 21:24:47 -07:00
include llist: make locking comments consistent 2026-05-28 21:24:46 -07:00
init treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
io_uring io_uring-7.1-20260522 2026-05-22 11:53:28 -07:00
ipc ipc: limit next_id allocation to the valid ID range 2026-05-21 19:06:11 -07:00
kernel kcov: refactor common handle ID into kcov_common_handle_id 2026-05-28 21:24:45 -07:00
lib uaccess: unify inline vs outline copy_{from,to}_user() selection 2026-05-28 21:24:44 -07:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm kfence: fix KASAN HW tags bypass via runtime sample_interval change 2026-05-28 21:24:46 -07:00
net 13 hotfixes. 9 are for MM. 9 are cc:stable and the remaining 4 address 2026-05-26 08:23:19 -07:00
rust uaccess: unify inline vs outline copy_{from,to}_user() selection 2026-05-28 21:24:44 -07:00
samples soc: drivers for 7.1 2026-04-16 20:34:34 -07:00
scripts get_maintainer: add --json output mode 2026-05-28 21:24:42 -07:00
security lsm/stable-7.1 PR 20260519 2026-05-19 15:31:35 -05:00
sound ASoC: Fixes for v7.1 2026-05-22 08:25:18 +02:00
tools kselftest/filelock: add a .gitignore file 2026-05-28 21:24:44 -07:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt KVM: Reject wrapped offset in kvm_reset_dirty_gfn() 2026-05-12 22:16:16 +02:00
.clang-format clang-format: fix formatting of guard() and scoped_guard() statements 2026-05-28 21:24:41 -07:00
.clippy.toml rust: bump Clippy's MSRV and clean incompatible_msrv allows 2026-04-07 09:51:39 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add myself 2026-04-02 16:48:25 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rust: provide an option to inline C helpers into Rust 2026-03-30 02:03:52 +02:00
.mailmap 13 hotfixes. 9 are for MM. 9 are cc:stable and the remaining 4 address 2026-05-26 08:23:19 -07:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS/CREDITS: remove inactive checkpatch reviewers 2026-05-28 21:24:46 -07:00
Kbuild checksyscalls: move instance functionality into generic code 2026-04-05 09:21:32 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS MAINTAINERS/CREDITS: remove inactive checkpatch reviewers 2026-05-28 21:24:46 -07:00
Makefile gcov: use atomic counter updates to fix concurrent access crashes 2026-05-28 21:24:46 -07:00
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros
* AI Coding Assistant - LLMs and AI-powered development tools


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst

AI Coding Assistant
-------------------

CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and
follow the AI coding assistants documentation before contributing to the Linux
kernel:

* Documentation/process/coding-assistants.rst

This documentation contains essential requirements about licensing, attribution,
and the Developer Certificate of Origin that all AI tools must comply with.


Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst