CVE-2023-53429

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> btrfs: don&amp;#39;t check PageError in __extent_writepage<br /> <br /> __extent_writepage currenly sets PageError whenever any error happens,<br /> and the also checks for PageError to decide if to call error handling.<br /> This leads to very unclear responsibility for cleaning up on errors.<br /> In the VM and generic writeback helpers the basic idea is that once<br /> I/O is fired off all error handling responsibility is delegated to the<br /> end I/O handler. But if that end I/O handler sets the PageError bit,<br /> and the submitter checks it, the bit could in some cases leak into the<br /> submission context for fast enough I/O.<br /> <br /> Fix this by simply not checking PageError and just using the local<br /> ret variable to check for submission errors. This also fundamentally<br /> solves the long problem documented in a comment in __extent_writepage<br /> by never leaking the error bit into the submission context.