kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-14 05:55:17 +00:00
Code Issues Releases Packages Activity
No description
917,553 commits 116 branches 5,791 tags 5.6 GiB
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Josef Bacik 0465337c55 btrfs: reset tree root pointer after error in init_tree_roots 
Eric reported an issue where mounting -o recovery with a fuzzed fs
resulted in a kernel panic.  This is because we tried to free the tree
node, except it was an error from the read.  Fix this by properly
resetting the tree_root->node == NULL in this case.  The panic was the
following

  BTRFS warning (device loop0): failed to read tree root
  BUG: kernel NULL pointer dereference, address: 000000000000001f
  RIP: 0010:free_extent_buffer+0xe/0x90 [btrfs]
  Call Trace:
   free_root_extent_buffers.part.0+0x11/0x30 [btrfs]
   free_root_pointers+0x1a/0xa2 [btrfs]
   open_ctree+0x1776/0x18a5 [btrfs]
   btrfs_mount_root.cold+0x13/0xfa [btrfs]
   ? selinux_fs_context_parse_param+0x37/0x80
   legacy_get_tree+0x27/0x40
   vfs_get_tree+0x25/0xb0
   fc_mount+0xe/0x30
   vfs_kern_mount.part.0+0x71/0x90
   btrfs_mount+0x147/0x3e0 [btrfs]
   ? cred_has_capability+0x7c/0x120
   ? legacy_get_tree+0x27/0x40
   legacy_get_tree+0x27/0x40
   vfs_get_tree+0x25/0xb0
   do_mount+0x735/0xa40
   __x64_sys_mount+0x8e/0xd0
   do_syscall_64+0x4d/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

Nik says: this is problematic only if we fail on the last iteration of
the loop as this results in init_tree_roots returning err value with
tree_root->node = -ERR. Subsequently the caller does: fail_tree_roots
which calls free_root_pointers on the bogus value.

Reported-by: Eric Sandeen <sandeen@redhat.com>
Fixes: b8522a1e5f ("btrfs: Factor out tree roots initialization during mount")
CC: stable@vger.kernel.org # 5.5+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add details how the pointer gets dereferenced ]
Signed-off-by: David Sterba <dsterba@suse.com>
History 2020-07-02 10:27:12 +02:00
arch A set of EFI fixes: 2020-05-24 10:24:10 -07:00
block bdi: use bdi_dev_name() to get device name 2020-05-09 16:07:39 -06:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto gcc-10: avoid shadowing standard library 'free()' in crypto 2020-05-09 15:58:04 -07:00
Documentation block: add bio_for_each_bvec_all() 2020-05-25 11:25:24 +02:00
drivers A set of EFI fixes: 2020-05-24 10:24:10 -07:00
fs btrfs: reset tree root pointer after error in init_tree_roots 2020-07-02 10:27:12 +02:00
include Revert "fs: remove dio_end_io()" 2020-06-09 19:23:18 +02:00
init A single fix for early boot crashes of kernels built with gcc10 and 2020-05-17 11:08:29 -07:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-14 10:00:35 -07:00
kernel A set of fixes for the scheduler: 2020-05-24 10:14:58 -07:00
lib vsprintf: don't obfuscate NULL and error pointers 2020-05-19 11:35:38 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm fs: export generic_file_buffered_read() 2020-05-25 13:12:37 +02:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-15 13:10:06 -07:00
scripts scripts/gdb: repair rb_first() and rb_last() 2020-05-07 19:27:20 -07:00
security Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
sound sound fixes for 5.7-rc7 2020-05-22 09:22:22 -07:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
usr kbuild: fix comment about missing include guard detection 2020-04-11 12:09:48 +09:00
virt KVM: Introduce kvm_make_all_cpus_request_except() 2020-05-08 07:44:32 -04:00
.clang-format block: add bio_for_each_bvec_all() 2020-05-25 11:25:24 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
.mailmap i2c: use my kernel.org address from now on 2020-05-05 16:29:09 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Hand MIPS over to Thomas 2020-02-24 22:43:18 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge branch 'akpm' (patches from Andrew) 2020-05-23 11:21:47 -07:00
Makefile Linux 5.7-rc7 2020-05-24 15:32:54 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.