Christian A. Ehrhardt 13f3956eb5 block: Fix WARNING in _copy_from_iter
Syzkaller reports a warning in _copy_from_iter because an
iov_iter is supposedly used in the wrong direction. The reason
is that syzcaller managed to generate a request with
a transfer direction of SG_DXFER_TO_FROM_DEV. This instructs
the kernel to copy user buffers into the kernel, read into
the copied buffers and then copy the data back to user space.

Thus the iovec is used in both directions.

Detect this situation in the block layer and construct a new
iterator with the correct direction for the copy-in.

Reported-by: syzbot+a532b03fdfee2c137666@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/0000000000009b92c10604d7a5e9@google.com/t/
Reported-by: syzbot+63dec323ac56c28e644f@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/0000000000003faaa105f6e7c658@google.com/T/
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240121202634.275068-1-lk@c--e.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-23 08:56:55 -07:00
2024-01-21 11:04:29 -08:00
2024-01-21 14:01:12 -08:00
2024-01-21 10:21:43 -08:00
2024-01-18 09:48:40 -08:00
2024-01-18 18:17:57 -08:00
2023-12-20 19:26:31 -05:00
2024-01-21 11:14:40 -08:00
2024-01-19 09:10:23 -08:00
2024-01-11 13:05:41 -08:00
2024-01-20 14:20:34 -08:00
2024-01-19 10:53:55 -08:00
2024-01-19 12:30:29 -08:00
2024-01-18 17:57:07 -08:00
2024-01-17 13:03:37 -08:00
2022-09-28 09:02:20 +02:00
2022-10-10 12:00:45 -07:00
2024-01-21 14:11:32 -08:00

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.
Description
Linux kernel stable tree
Readme 6.1 GiB
Languages
C 97.5%
Assembly 1%
Shell 0.6%
Python 0.3%
Makefile 0.3%