No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Alexander Potapenko ed8b990e89 mm: fs: initialize fsdata passed to write_begin/write_end interface
commit 1468c6f4558b1bcd92aa0400f2920f9dc7588402 upstream.

Functions implementing the a_ops->write_end() interface accept the `void
*fsdata` parameter that is supposed to be initialized by the corresponding
a_ops->write_begin() (which accepts `void **fsdata`).

However not all a_ops->write_begin() implementations initialize `fsdata`
unconditionally, so it may get passed uninitialized to a_ops->write_end(),
resulting in undefined behavior.

Fix this by initializing fsdata with NULL before the call to
write_begin(), rather than doing so in all possible a_ops implementations.

This patch covers only the following cases found by running x86 KMSAN
under syzkaller:

 - generic_perform_write()
 - cont_expand_zero() and generic_cont_expand_simple()
 - page_symlink()

Other cases of passing uninitialized fsdata may persist in the codebase.

Link: https://lkml.kernel.org/r/20220915150417.722975-43-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:42:22 +01:00
arch arm64: dts: imx8mn: Fix NAND controller size-cells 2022-11-25 17:42:15 +01:00
block block: sed-opal: kmalloc the cmd/resp buffers 2022-11-25 17:42:14 +01:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: akcipher - default implementation for setting a private key 2022-10-26 13:22:45 +02:00
Documentation docs: update mediator contact information in CoC doc 2022-11-25 17:42:20 +01:00
drivers macvlan: enforce a consistent minimal mtu 2022-11-25 17:42:21 +01:00
fs mm: fs: initialize fsdata passed to write_begin/write_end interface 2022-11-25 17:42:22 +01:00
include vmlinux.lds.h: Fix placement of '.data..decrypted' section 2022-11-25 17:42:09 +01:00
init random: handle latent entropy and command line from random_init() 2022-06-22 14:11:17 +02:00
ipc ipc: remove memcg accounting for sops objects in do_semtimedop() 2022-11-10 17:57:58 +01:00
kernel kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case 2022-11-25 17:42:21 +01:00
lib dyndbg: let query-modname override actual module name 2022-10-26 13:22:37 +02:00
LICENSES
mm mm: fs: initialize fsdata passed to write_begin/write_end interface 2022-11-25 17:42:22 +01:00
net 9p/trans_fd: always use O_NONBLOCK read/write 2022-11-25 17:42:22 +01:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-17 09:48:39 +01:00
scripts cert host tools: Stop complaining about deprecated OpenSSL functions 2022-11-25 17:42:10 +01:00
security capabilities: fix potential memleak on error path from vfs_getxattr_alloc() 2022-11-10 17:57:55 +01:00
sound ALSA: usb-audio: Drop snd_BUG_ON() from snd_usbmidi_output_open() 2022-11-25 17:42:17 +01:00
tools selftests/intel_pstate: fix build for ARCH=x86_64 2022-11-25 17:42:12 +01:00
usr initramfs: restore default compression behavior 2020-04-08 09:08:38 +02:00
virt KVM: arm64: vgic: Fix exit condition in scan_its_table() 2022-10-29 10:20:35 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS MAINTAINERS: add Chandan as xfs maintainer for 5.4.y 2022-09-28 11:03:58 +02:00
Makefile Linux 5.4.224 2022-11-10 17:57:58 +01:00
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.