linux.git/drivers/misc/vmw_vmci, branch v6.9-rc2

VMCI: Fix possible memcpy() run-time warning in vmci_datagram_invoke_guest_handler()

2024-03-02T00:03:32+00:00

The changes are similar to those given in the commit 19b070fefd0d
("VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()").

Fix filling of the msg and msg_payload in dg_info struct, which prevents a
possible "detected field-spanning write" of memcpy warning that is issued
by the tracking mechanism __fortify_memcpy_chk.

Signed-off-by: Vasiliy Kovalev 
Link: https://lore.kernel.org/r/20240219105315.76955-1-kovalev@altlinux.org
Signed-off-by: Kees Cook

VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()

2024-02-01T18:06:42+00:00

Syzkaller hit 'WARNING in dg_dispatch_as_host' bug.

memcpy: detected field-spanning write (size 56) of single field "&dg_info->msg"
at drivers/misc/vmw_vmci/vmci_datagram.c:237 (size 24)

WARNING: CPU: 0 PID: 1555 at drivers/misc/vmw_vmci/vmci_datagram.c:237
dg_dispatch_as_host+0x88e/0xa60 drivers/misc/vmw_vmci/vmci_datagram.c:237

Some code commentry, based on my understanding:

544 #define VMCI_DG_SIZE(_dg) (VMCI_DG_HEADERSIZE + (size_t)(_dg)->payload_size)
/// This is 24 + payload_size

memcpy(&dg_info->msg, dg, dg_size);
	Destination = dg_info->msg ---> this is a 24 byte
					structure(struct vmci_datagram)
	Source = dg --> this is a 24 byte structure (struct vmci_datagram)
	Size = dg_size = 24 + payload_size

{payload_size = 56-24 =32} -- Syzkaller managed to set payload_size to 32.

 35 struct delayed_datagram_info {
 36         struct datagram_entry *entry;
 37         struct work_struct work;
 38         bool in_dg_host_queue;
 39         /* msg and msg_payload must be together. */
 40         struct vmci_datagram msg;
 41         u8 msg_payload[];
 42 };

So those extra bytes of payload are copied into msg_payload[], a run time
warning is seen while fuzzing with Syzkaller.

One possible way to fix the warning is to split the memcpy() into
two parts -- one -- direct assignment of msg and second taking care of payload.

Gustavo quoted:
"Under FORTIFY_SOURCE we should not copy data across multiple members
in a structure."

Reported-by: syzkaller 
Suggested-by: Vegard Nossum 
Suggested-by: Gustavo A. R. Silva 
Signed-off-by: Harshit Mogalapalli 
Reviewed-by: Gustavo A. R. Silva 
Reviewed-by: Kees Cook 
Reviewed-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20240105164001.2129796-2-harshit.m.mogalapalli@oracle.com
Signed-off-by: Kees Cook

VMCI: Use struct_size() in kmalloc()

2024-02-01T18:06:42+00:00

Use struct_size() instead of open coding.

Suggested-by: Gustavo A. R. Silva 
Signed-off-by: Harshit Mogalapalli 
Reviewed-by: Kees Cook 
Reviewed-by: Gustavo A. R. Silva 
Link: https://lore.kernel.org/r/20240105164001.2129796-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Kees Cook

Merge tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2024-01-18T00:47:17+00:00

Pull char/misc and other driver updates from Greg KH:
 "Here is the big set of char/misc and other driver subsystem changes
  for 6.8-rc1.

  Other than lots of binder driver changes (as you can see by the merge
  conflicts) included in here are:

   - lots of iio driver updates and additions

   - spmi driver updates

   - eeprom driver updates

   - firmware driver updates

   - ocxl driver updates

   - mhi driver updates

   - w1 driver updates

   - nvmem driver updates

   - coresight driver updates

   - platform driver remove callback api changes

   - tags.sh script updates

   - bus_type constant marking cleanups

   - lots of other small driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (341 commits)
  android: removed duplicate linux/errno
  uio: Fix use-after-free in uio_open
  drivers: soc: xilinx: add check for platform
  firmware: xilinx: Export function to use in other module
  scripts/tags.sh: remove find_sources
  scripts/tags.sh: use -n to test archinclude
  scripts/tags.sh: add local annotation
  scripts/tags.sh: use more portable -path instead of -wholename
  scripts/tags.sh: Update comment (addition of gtags)
  firmware: zynqmp: Convert to platform remove callback returning void
  firmware: turris-mox-rwtm: Convert to platform remove callback returning void
  firmware: stratix10-svc: Convert to platform remove callback returning void
  firmware: stratix10-rsu: Convert to platform remove callback returning void
  firmware: raspberrypi: Convert to platform remove callback returning void
  firmware: qemu_fw_cfg: Convert to platform remove callback returning void
  firmware: mtk-adsp-ipc: Convert to platform remove callback returning void
  firmware: imx-dsp: Convert to platform remove callback returning void
  firmware: coreboot_table: Convert to platform remove callback returning void
  firmware: arm_scpi: Convert to platform remove callback returning void
  firmware: arm_scmi: Convert to platform remove callback returning void
  ...

VMCI: Remove VMCI_HANDLE_ARRAY_HEADER_SIZE and VMCI_HANDLE_ARRAY_MAX_CAPACITY

2023-12-15T16:27:04+00:00

Remove VMCI_HANDLE_ARRAY_HEADER_SIZE and VMCI_HANDLE_ARRAY_MAX_CAPACITY
that are unused.

Suggested-by: Kees Cook 
Signed-off-by: Christophe JAILLET 
Reviewed-by: Kees Cook 
Link: https://lore.kernel.org/r/00547fe74efe329b266eb8074c41f286758a3c64.1702125347.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman

VMCI: Remove handle_arr_calc_size()

2023-12-15T16:27:04+00:00

Use struct_size() instead of handle_arr_calc_size().
This is much more conventional.

While at it, use size_add() when computing the needed size in
vmci_handle_arr_append_entry(). This prevents from (unlikely) overflow
when computing the new size to reallocate.

Suggested-by: Kees Cook 
Signed-off-by: Christophe JAILLET 
Reviewed-by: Kees Cook 
Link: https://lore.kernel.org/r/84e7f2d8e7c4c2eab68f958307d56546978f76e3.1702125347.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman

VMCI: Annotate struct vmci_handle_arr with __counted_by

2023-12-01T17:51:43+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

Signed-off-by: Christophe JAILLET 
Reviewed-by: Kees Cook 
Link: https://lore.kernel.org/r/56bef519d982218176b59bbba64a3a308d8733d5.1696689091.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Kees Cook

Merge tag 'char-misc-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2023-04-27T19:07:50+00:00

Pull char/misc drivers updates from Greg KH:
 "Here is the "big" set of char/misc and other driver subsystems for
  6.4-rc1.

  It's pretty big, but due to the removal of pcmcia drivers, almost
  breaks even for number of lines added vs. removed, a nice change.

  Included in here are:

   - removal of unused PCMCIA drivers (finally!)

   - Interconnect driver updates and additions

   - Lots of IIO driver updates and additions

   - MHI driver updates

   - Coresight driver updates

   - NVMEM driver updates, which required some OF updates

   - W1 driver updates and a new maintainer to manage the subsystem

   - FPGA driver updates

   - New driver subsystem, CDX, for AMD systems

   - lots of other small driver updates and additions

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (196 commits)
  mcb-lpc: Reallocate memory region to avoid memory overlapping
  mcb-pci: Reallocate memory region to avoid memory overlapping
  mcb: Return actual parsed size when reading chameleon table
  kernel/configs: Drop Android config fragments
  virt: acrn: Replace obsolete memalign() with posix_memalign()
  spmi: Add a check for remove callback when removing a SPMI driver
  spmi: fix W=1 kernel-doc warnings
  spmi: mtk-pmif: Drop of_match_ptr for ID table
  spmi: pmic-arb: Convert to platform remove callback returning void
  spmi: mtk-pmif: Convert to platform remove callback returning void
  spmi: hisi-spmi-controller: Convert to platform remove callback returning void
  w1: gpio: remove unnecessary ENOMEM messages
  w1: omap-hdq: remove unnecessary ENOMEM messages
  w1: omap-hdq: add SPDX tag
  w1: omap-hdq: allow compile testing
  w1: matrox: remove unnecessary ENOMEM messages
  w1: matrox: use inline over __inline__
  w1: matrox: switch from asm to linux header
  w1: ds2482: do not use assignment in if condition
  w1: ds2482: drop unnecessary header
  ...

vmci_host: fix a race condition in vmci_host_poll() causing GPF

2023-04-05T17:37:35+00:00

During fuzzing, a general protection fault is observed in
vmci_host_poll().

general protection fault, probably for non-canonical address 0xdffffc0000000019: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf]
RIP: 0010:__lock_acquire+0xf3/0x5e00 kernel/locking/lockdep.c:4926
<- omitting registers ->
Call Trace:
 
 lock_acquire+0x1a4/0x4a0 kernel/locking/lockdep.c:5672
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xb3/0x100 kernel/locking/spinlock.c:162
 add_wait_queue+0x3d/0x260 kernel/sched/wait.c:22
 poll_wait include/linux/poll.h:49 [inline]
 vmci_host_poll+0xf8/0x2b0 drivers/misc/vmw_vmci/vmci_host.c:174
 vfs_poll include/linux/poll.h:88 [inline]
 do_pollfd fs/select.c:873 [inline]
 do_poll fs/select.c:921 [inline]
 do_sys_poll+0xc7c/0x1aa0 fs/select.c:1015
 __do_sys_ppoll fs/select.c:1121 [inline]
 __se_sys_ppoll+0x2cc/0x330 fs/select.c:1101
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4e/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Example thread interleaving that causes the general protection fault
is as follows:

CPU1 (vmci_host_poll)               CPU2 (vmci_host_do_init_context)
-----                               -----
// Read uninitialized context
context = vmci_host_dev->context;
                                    // Initialize context
                                    vmci_host_dev->context = vmci_ctx_create();
                                    vmci_host_dev->ct_type = VMCIOBJ_CONTEXT;

if (vmci_host_dev->ct_type == VMCIOBJ_CONTEXT) {
    // Dereferencing the wrong pointer
    poll_wait(..., &context->host_context);
}

In this scenario, vmci_host_poll() reads vmci_host_dev->context first,
and then reads vmci_host_dev->ct_type to check that
vmci_host_dev->context is initialized. However, since these two reads
are not atomically executed, there is a chance of a race condition as
described above.

To fix this race condition, read vmci_host_dev->context after checking
the value of vmci_host_dev->ct_type so that vmci_host_poll() always
reads an initialized context.

Reported-by: Dae R. Jeong 
Fixes: 8bf503991f87 ("VMCI: host side driver implementation.")
Signed-off-by: Dae R. Jeong 
Link: https://lore.kernel.org/r/ZCGFsdBAU4cYww5l@dragonet
Signed-off-by: Greg Kroah-Hartman

misc: vmw_vmci: Rename kvfree_rcu() to kvfree_rcu_mightsleep()

2023-04-05T13:48:03+00:00

The kvfree_rcu() macro's single-argument form is deprecated.  Therefore
switch to the new kvfree_rcu_mightsleep() variant. The goal is to
avoid accidental use of the single-argument forms, which can introduce
functionality bugs in atomic contexts and latency bugs in non-atomic
contexts.

Cc: Bryan Tan 
Cc: Vishnu Dasa 
Reviewed-by: Vishnu Dasa 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: Uladzislau Rezki (Sony) 
Signed-off-by: Paul E. McKenney 
Signed-off-by: Joel Fernandes (Google)