62720f2daa
commit 2f02b5af3a4482b216e6a466edecf6ba8450fa45 upstream.
The violation of atomicity occurs when the drbd_uuid_set_bm function is
executed simultaneously with modifying the value of
device->ldev->md.uuid[UI_BITMAP]. Consider a scenario where, while
device->ldev->md.uuid[UI_BITMAP] passes the validity check when its
value is not zero, the value of device->ldev->md.uuid[UI_BITMAP] is
written to zero. In this case, the check in drbd_uuid_set_bm might refer
to the old value of device->ldev->md.uuid[UI_BITMAP] (before locking),
which allows an invalid value to pass the validity check, resulting in
inconsistency.
To address this issue, it is recommended to include the data validity
check within the locked section of the function. This modification
ensures that the value of device->ldev->md.uuid[UI_BITMAP] does not
change during the validation process, thereby maintaining its integrity.
This possible bug is found by an experimental static analysis tool
developed by our team. This tool analyzes the locking APIs to extract
function pairs that can be concurrently executed, and then analyzes the
instructions in the paired functions to identify possible concurrency
bugs including data races and atomicity violations.
Fixes:
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||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| 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 | ||
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.