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Paulo Alcantara 6db94d0835 smb: client: fix use-after-free in smb2_query_info_compound()
commit 5c86919455 upstream.

The following UAF was triggered when running fstests generic/072 with
KASAN enabled against Windows Server 2022 and mount options
'multichannel,max_channels=2,vers=3.1.1,mfsymlinks,noperm'

  BUG: KASAN: slab-use-after-free in smb2_query_info_compound+0x423/0x6d0 [cifs]
  Read of size 8 at addr ffff888014941048 by task xfs_io/27534

  CPU: 0 PID: 27534 Comm: xfs_io Not tainted 6.6.0-rc7 #1
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0x7f
   ? srso_alias_return_thunk+0x5/0x7f
   ? __phys_addr+0x46/0x90
   kasan_report+0xda/0x110
   ? smb2_query_info_compound+0x423/0x6d0 [cifs]
   ? smb2_query_info_compound+0x423/0x6d0 [cifs]
   smb2_query_info_compound+0x423/0x6d0 [cifs]
   ? __pfx_smb2_query_info_compound+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0x7f
   ? __stack_depot_save+0x39/0x480
   ? kasan_save_stack+0x33/0x60
   ? kasan_set_track+0x25/0x30
   ? ____kasan_slab_free+0x126/0x170
   smb2_queryfs+0xc2/0x2c0 [cifs]
   ? __pfx_smb2_queryfs+0x10/0x10 [cifs]
   ? __pfx___lock_acquire+0x10/0x10
   smb311_queryfs+0x210/0x220 [cifs]
   ? __pfx_smb311_queryfs+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0x7f
   ? __lock_acquire+0x480/0x26c0
   ? lock_release+0x1ed/0x640
   ? srso_alias_return_thunk+0x5/0x7f
   ? do_raw_spin_unlock+0x9b/0x100
   cifs_statfs+0x18c/0x4b0 [cifs]
   statfs_by_dentry+0x9b/0xf0
   fd_statfs+0x4e/0xb0
   __do_sys_fstatfs+0x7f/0xe0
   ? __pfx___do_sys_fstatfs+0x10/0x10
   ? srso_alias_return_thunk+0x5/0x7f
   ? lockdep_hardirqs_on_prepare+0x136/0x200
   ? srso_alias_return_thunk+0x5/0x7f
   do_syscall_64+0x3f/0x90
   entry_SYSCALL_64_after_hwframe+0x6e/0xd8

  Allocated by task 27534:
   kasan_save_stack+0x33/0x60
   kasan_set_track+0x25/0x30
   __kasan_kmalloc+0x8f/0xa0
   open_cached_dir+0x71b/0x1240 [cifs]
   smb2_query_info_compound+0x5c3/0x6d0 [cifs]
   smb2_queryfs+0xc2/0x2c0 [cifs]
   smb311_queryfs+0x210/0x220 [cifs]
   cifs_statfs+0x18c/0x4b0 [cifs]
   statfs_by_dentry+0x9b/0xf0
   fd_statfs+0x4e/0xb0
   __do_sys_fstatfs+0x7f/0xe0
   do_syscall_64+0x3f/0x90
   entry_SYSCALL_64_after_hwframe+0x6e/0xd8

  Freed by task 27534:
   kasan_save_stack+0x33/0x60
   kasan_set_track+0x25/0x30
   kasan_save_free_info+0x2b/0x50
   ____kasan_slab_free+0x126/0x170
   slab_free_freelist_hook+0xd0/0x1e0
   __kmem_cache_free+0x9d/0x1b0
   open_cached_dir+0xff5/0x1240 [cifs]
   smb2_query_info_compound+0x5c3/0x6d0 [cifs]
   smb2_queryfs+0xc2/0x2c0 [cifs]

This is a race between open_cached_dir() and cached_dir_lease_break()
where the cache entry for the open directory handle receives a lease
break while creating it.  And before returning from open_cached_dir(),
we put the last reference of the new @cfid because of
!@cfid->has_lease.

Besides the UAF, while running xfstests a lot of missed lease breaks
have been noticed in tests that run several concurrent statfs(2) calls
on those cached fids

  CIFS: VFS: \\w22-root1.gandalf.test No task to wake, unknown frame...
  CIFS: VFS: \\w22-root1.gandalf.test Cmd: 18 Err: 0x0 Flags: 0x1...
  CIFS: VFS: \\w22-root1.gandalf.test smb buf 00000000715bfe83 len 108
  CIFS: VFS: Dump pending requests:
  CIFS: VFS: \\w22-root1.gandalf.test No task to wake, unknown frame...
  CIFS: VFS: \\w22-root1.gandalf.test Cmd: 18 Err: 0x0 Flags: 0x1...
  CIFS: VFS: \\w22-root1.gandalf.test smb buf 000000005aa7316e len 108
  ...

To fix both, in open_cached_dir() ensure that @cfid->has_lease is set
right before sending out compounded request so that any potential
lease break will be get processed by demultiplex thread while we're
still caching @cfid.  And, if open failed for some reason, re-check
@cfid->has_lease to decide whether or not put lease reference.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:15:11 +00:00
arch parisc/pgtable: Do not drop upper 5 address bits of physical address 2023-11-28 17:15:10 +00:00
block blk-mq: make sure active queue usage is held for bio_integrity_prep() 2023-11-28 17:14:55 +00:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 17:14:46 +00:00
Documentation torture: Add lock_torture writer_fifo module parameter 2023-11-28 17:15:09 +00:00
drivers xhci: Enable RPM on controllers that support low-power states 2023-11-28 17:15:10 +00:00
fs smb: client: fix use-after-free in smb2_query_info_compound() 2023-11-28 17:15:11 +00:00
include fs: add ctime accessors infrastructure 2023-11-28 17:15:10 +00:00
init proc: sysctl: prevent aliased sysctls from getting passed to init 2023-11-28 17:15:00 +00:00
io_uring io_uring/fdinfo: remove need for sqpoll lock for thread/pid retrieval 2023-11-28 17:14:56 +00:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel rcutorture: Fix stuttering races and other issues 2023-11-28 17:15:10 +00:00
lib lib/generic-radix-tree.c: Don't overflow in peek() 2023-11-28 17:14:40 +00:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm/hugetlb: use nth_page() in place of direct struct page manipulation 2023-11-28 17:15:10 +00:00
net netfilter: nf_tables: split async and sync catchall in two functions 2023-11-28 17:15:06 +00:00
rust rust: types: make Opaque be !Unpin 2023-11-08 14:09:04 +01:00
samples samples/bpf: syscall_tp_user: Fix array out-of-bound access 2023-11-28 17:14:52 +00:00
scripts randstruct: Fix gcc-plugin performance mode to stay in group 2023-11-28 17:14:58 +00:00
security ima: detect changes to the backing overlay file 2023-11-28 17:15:06 +00:00
sound ASoC: codecs: wsa-macro: fix uninitialized stack variables with name prefix 2023-11-28 17:15:07 +00:00
tools cxl/region: Fix x1 root-decoder granularity calculations 2023-11-28 17:15:09 +00:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add() 2023-09-13 09:53:29 +02:00
.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 Revert ".gitignore: ignore *.cover and *.mbx" 2023-07-04 15:05:12 -07:00
.mailmap mailmap: add entries for Simon Horman 2023-08-16 09:53:10 +01:00
.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 - Address -Wmissing-prototype warnings 2023-06-26 16:43:54 -07:00
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 sound fixes for 6.5 2023-08-25 08:48:14 -07:00
Makefile Linux 6.5.12 2023-11-20 11:57:26 +01:00
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.