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Jinjie Ruan c777b11d34 vfio/mdev: Fix a null-ptr-deref bug for mdev_unregister_parent()
Inject fault while probing mdpy.ko, if kstrdup() of create_dir() fails in
kobject_add_internal() in kobject_init_and_add() in mdev_type_add()
in parent_create_sysfs_files(), it will return 0 and probe successfully.
And when rmmod mdpy.ko, the mdpy_dev_exit() will call
mdev_unregister_parent(), the mdev_type_remove() may traverse uninitialized
parent->types[i] in parent_remove_sysfs_files(), and it will cause
below null-ptr-deref.

If mdev_type_add() fails, return the error code and kset_unregister()
to fix the issue.

 general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
 KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
 CPU: 2 PID: 10215 Comm: rmmod Tainted: G        W        N 6.6.0-rc2+ #20
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
 RIP: 0010:__kobject_del+0x62/0x1c0
 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8
 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202
 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010
 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1
 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000
 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660
 FS:  00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0
 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea
 DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? die_addr+0x3d/0xa0
  ? exc_general_protection+0x144/0x220
  ? asm_exc_general_protection+0x22/0x30
  ? __kobject_del+0x62/0x1c0
  kobject_del+0x32/0x50
  parent_remove_sysfs_files+0xd6/0x170 [mdev]
  mdev_unregister_parent+0xfb/0x190 [mdev]
  ? mdev_register_parent+0x270/0x270 [mdev]
  ? find_module_all+0x9d/0xe0
  mdpy_dev_exit+0x17/0x63 [mdpy]
  __do_sys_delete_module.constprop.0+0x2fa/0x4b0
  ? module_flags+0x300/0x300
  ? __fput+0x4e7/0xa00
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x46/0xb0
 RIP: 0033:0x7fbc813221b7
 Code: 73 01 c3 48 8b 0d d1 8c 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 8c 2c 00 f7 d8 64 89 01 48
 RSP: 002b:00007ffe780e0648 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
 RAX: ffffffffffffffda RBX: 00007ffe780e06a8 RCX: 00007fbc813221b7
 RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055e214df9b58
 RBP: 000055e214df9af0 R08: 00007ffe780df5c1 R09: 0000000000000000
 R10: 00007fbc8139ecc0 R11: 0000000000000206 R12: 00007ffe780e0870
 R13: 00007ffe780e0ed0 R14: 000055e214df9260 R15: 000055e214df9af0
  </TASK>
 Modules linked in: mdpy(-) mdev vfio_iommu_type1 vfio [last unloaded: mdpy]
 Dumping ftrace buffer:
    (ftrace buffer empty)
 ---[ end trace 0000000000000000 ]---
 RIP: 0010:__kobject_del+0x62/0x1c0
 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8
 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202
 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010
 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1
 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000
 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660
 FS:  00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0
 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea
 DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600
 PKRU: 55555554
 Kernel panic - not syncing: Fatal exception
 Dumping ftrace buffer:
    (ftrace buffer empty)
 Kernel Offset: disabled
 Rebooting in 1 seconds..

Fixes: da44c340c4 ("vfio/mdev: simplify mdev_type handling")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230918115551.1423193-1-ruanjinjie@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-09-22 12:48:04 -06:00
arch Misc fixes: 2023-09-17 11:13:37 -07:00
block blk-mq: fix tags UAF when shrinking q->nr_hw_queues 2023-09-11 16:17:34 -06:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto This update includes the following changes: 2023-08-29 11:23:29 -07:00
Documentation Driver core fix for 6.6-rc2 2023-09-16 11:26:52 -07:00
drivers vfio/mdev: Fix a null-ptr-deref bug for mdev_unregister_parent() 2023-09-22 12:48:04 -06:00
fs stat: remove no-longer-used helper macros 2023-09-17 10:46:12 -07:00
include Misc fixes: 2023-09-17 11:13:37 -07:00
init workqueue: Changes for v6.6 2023-09-01 16:06:32 -07:00
io_uring io_uring/net: fix iter retargeting for selected buf 2023-09-14 10:12:55 -06:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel Fix a performance regression on large SMT systems, an Intel SMT4 2023-09-17 11:10:23 -07:00
lib linux-kselftest-kunit-6.6-rc2 2023-09-12 09:05:49 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm vm: fix move_vma() memory accounting being off 2023-09-16 15:23:31 -07:00
net kcm: Fix error handling for SOCK_DGRAM in kcm_sendmsg(). 2023-09-14 10:43:51 +02:00
rust Documentation work keeps chugging along; stuff for 6.6 includes: 2023-08-30 20:05:42 -07:00
samples VFIO updates for v6.6-rc1 2023-08-30 20:36:01 -07:00
scripts Kbuild fixes for v6.6 2023-09-16 15:27:00 -07:00
security selinux: fix handling of empty opts in selinux_fs_context_submount() 2023-09-12 17:31:08 -04:00
sound sound fixes for 6.6-rc1 2023-09-08 13:07:50 -07:00
tools Fix a cold functions related false-positive objtool warning 2023-09-17 10:59:37 -07:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap for-linus-2023083101 2023-09-01 12:31:44 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS This pull-request renames the genpd subsystem to pmdomain. 2023-09-13 14:18:19 -07:00
Makefile Linux 6.6-rc2 2023-09-17 14:40:24 -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.