A mirror of the official Linux kernel repository just in case
Go to file
Borislav Petkov 251c54ea26 EDAC/ghes: Check whether the driver is on the safe list correctly
With CONFIG_DEBUG_TEST_DRIVER_REMOVE=y, a system would try to probe,
unregister and probe again a driver.

When ghes_edac is attempted to be loaded on a system which is not on
the safe platforms list, ghes_edac_register() would return early. The
unregister counterpart ghes_edac_unregister() would still attempt to
unregister and exit early at the refcount test, leading to the refcount
underflow below.

In order to not do *anything* on the unregister path too, reuse the
force_load parameter and check it on that path too, before fumbling with
the refcount.

  ghes_edac: ghes_edac_register: entry
  ghes_edac: ghes_edac_register: return -ENODEV
  ------------[ cut here ]------------
  refcount_t: underflow; use-after-free.
  WARNING: CPU: 10 PID: 1 at lib/refcount.c:28 refcount_warn_saturate+0xb9/0x100
  Modules linked in:
  CPU: 10 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc4+ #12
  Hardware name: GIGABYTE MZ01-CE1-00/MZ01-CE1-00, BIOS F02 08/29/2018
  RIP: 0010:refcount_warn_saturate+0xb9/0x100
  Code: 82 e8 fb 8f 4d 00 90 0f 0b 90 90 c3 80 3d 55 4c f5 00 00 75 88 c6 05 4c 4c f5 00 01 90 48 c7 c7 d0 8a 10 82 e8 d8 8f 4d 00 90 <0f> 0b 90 90 c3 80 3d 30 4c f5 00 00 0f 85 61 ff ff ff c6 05 23 4c
  RSP: 0018:ffffc90000037d58 EFLAGS: 00010292
  RAX: 0000000000000026 RBX: ffff88840b8da000 RCX: 0000000000000000
  RDX: 0000000000000001 RSI: ffffffff8216b24f RDI: 00000000ffffffff
  RBP: ffff88840c662e00 R08: 0000000000000001 R09: 0000000000000001
  R10: 0000000000000001 R11: 0000000000000046 R12: 0000000000000000
  R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
  FS:  0000000000000000(0000) GS:ffff88840ee80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 0000800002211000 CR4: 00000000003506e0
  Call Trace:
   ghes_edac_unregister
   ghes_remove
   platform_drv_remove
   really_probe
   driver_probe_device
   device_driver_attach
   __driver_attach
   ? device_driver_attach
   ? device_driver_attach
   bus_for_each_dev
   bus_add_driver
   driver_register
   ? bert_init
   ghes_init
   do_one_initcall
   ? rcu_read_lock_sched_held
   kernel_init_freeable
   ? rest_init
   kernel_init
   ret_from_fork
   ...
  ghes_edac: ghes_edac_unregister: FALSE, refcount: -1073741824

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200911164950.GB19320@zn.tnic
2020-09-15 09:42:15 +02:00
arch ARM: SoC fixes 2020-09-13 14:54:40 -07:00
block - Fix a regression in bdev partition locking (Christoph) 2020-09-11 11:55:28 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-08-30 15:53:44 -07:00
Documentation ARM: SoC fixes 2020-09-13 14:54:40 -07:00
drivers EDAC/ghes: Check whether the driver is on the safe list correctly 2020-09-15 09:42:15 +02:00
fs Driver core fixes for 5.9-rc5 2020-09-13 09:02:59 -07:00
include Driver core fixes for 5.9-rc5 2020-09-13 09:02:59 -07:00
init init: fix error check in clean_path() 2020-09-04 09:16:58 -07:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel seccomp fixes for v5.9-rc5 2020-09-12 12:58:01 -07:00
lib Driver core fixes for 5.9-rc5 2020-09-13 09:02:59 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm xen: branch for v5.9-rc4 2020-09-06 09:59:27 -07:00
net NFS client bugfixes for Linux 5.9 2020-09-09 11:14:20 -07:00
samples treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
scripts Char / Misc driver fixes for 5.9-rc5 2020-09-13 08:52:21 -07:00
security treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sound sound fixes for 5.9-rc4 2020-09-04 12:05:25 -07:00
tools KVM/arm64 fixes for Linux 5.9, take #1 2020-09-11 13:12:11 -04:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM: fix memory leak in kvm_io_bus_unregister_dev() 2020-09-11 13:15:11 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2020-09-01 12:53:42 +02:00
.cocciconfig
.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 ZSTD-compressed files 2020-07-31 11:50:49 +02:00
.mailmap mailmap, MAINTAINERS: move to tycho.pizza 2020-09-08 11:29:57 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS CREDITS: Replace HTTP links with HTTPS ones 2020-07-23 14:53:58 -06:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Driver core fixes for 5.9-rc5 2020-09-13 09:02:59 -07:00
Makefile Linux 5.9-rc5 2020-09-13 16:06:00 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.