linux.git/drivers/misc, branch v4.19.59

VMCI: Fix integer overflow in VMCI handle arrays

2019-07-14T06:11:21+00:00

commit 1c2eb5b2853c9f513690ba6b71072d8eb65da16a upstream.

The VMCI handle array has an integer overflow in
vmci_handle_arr_append_entry when it tries to expand the array. This can be
triggered from a guest, since the doorbell link hypercall doesn't impose a
limit on the number of doorbell handles that a VM can create in the
hypervisor, and these handles are stored in a handle array.

In this change, we introduce a mandatory max capacity for handle
arrays/lists to avoid excessive memory usage.

Signed-off-by: Vishnu Dasa 
Reviewed-by: Adit Ranadive 
Reviewed-by: Jorgen Hansen 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

lkdtm: support llvm-objcopy

2019-07-14T06:11:21+00:00

commit e9e08a07385e08f1a7f85c5d1e345c21c9564963 upstream.

With CONFIG_LKDTM=y and make OBJCOPY=llvm-objcopy, llvm-objcopy errors:
llvm-objcopy: error: --set-section-flags=.text conflicts with
--rename-section=.text=.rodata

Rather than support setting flags then renaming sections vs renaming
then setting flags, it's simpler to just change both at the same time
via --rename-section. Adding the load flag is required for GNU objcopy
to mark .rodata Type as PROGBITS after the rename.

This can be verified with:
$ readelf -S drivers/misc/lkdtm/rodata_objcopy.o
...
Section Headers:
  [Nr] Name              Type             Address           Offset
       Size              EntSize          Flags  Link  Info  Align
...
  [ 1] .rodata           PROGBITS         0000000000000000  00000040
       0000000000000004  0000000000000000   A       0     0     4
...

Which shows that .text is now renamed .rodata, the alloc flag A is set,
the type is PROGBITS, and the section is not flagged as writeable W.

Cc: stable@vger.kernel.org
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=24554
Link: https://github.com/ClangBuiltLinux/linux/issues/448
Reported-by: Nathan Chancellor 
Suggested-by: Alan Modra 
Suggested-by: Jordan Rupprect 
Suggested-by: Kees Cook 
Acked-by: Kees Cook 
Reviewed-by: Nathan Chancellor 
Signed-off-by: Nick Desaulniers 
Signed-off-by: Greg Kroah-Hartman

eeprom: at24: fix unexpected timeout under high load

2019-07-03T11:14:46+00:00

commit 9a9e295e7c5c0409c020088b0ae017e6c2b7df6e upstream.

Within at24_loop_until_timeout the timestamp used for timeout checking
is recorded after the I2C transfer and sleep_range(). Under high CPU
load either the execution time for I2C transfer or sleep_range() could
actually be larger than the timeout value. Worst case the I2C transfer
is only tried once because the loop will exit due to the timeout
although the EEPROM is now ready.

To fix this issue the timestamp is recorded at the beginning of each
iteration. That is, before I2C transfer and sleep. Then the timeout
is actually checked against the timestamp of the previous iteration.
This makes sure that even if the timeout is reached, there is still one
more chance to try the I2C transfer in case the EEPROM is ready.

Example:

If you have a system which combines high CPU load with repeated EEPROM
writes you will run into the following scenario.

 - System makes a successful regmap_bulk_write() to EEPROM.
 - System wants to perform another write to EEPROM but EEPROM is still
   busy with the last write.
 - Because of high CPU load the usleep_range() will sleep more than
   25 ms (at24_write_timeout).
 - Within the over-long sleeping the EEPROM finished the previous write
   operation and is ready again.
 - at24_loop_until_timeout() will detect timeout and won't try to write.

Signed-off-by: Wang Xin 
Signed-off-by: Mark Jonas 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

Drivers: misc: fix out-of-bounds access in function param_set_kgdbts_var

2019-06-19T06:18:02+00:00

[ Upstream commit b281218ad4311a0342a40cb02fb17a363df08b48 ]

There is an out-of-bounds access to "config[len - 1]" array when the
variable "len" is zero.

See commit dada6a43b040 ("kgdboc: fix KASAN global-out-of-bounds bug
in param_set_kgdboc_var()") for details.

Signed-off-by: Young Xiao 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

misc: pci_endpoint_test: Fix test_reg_bar to be updated in pci_endpoint_test

2019-06-15T09:54:06+00:00

[ Upstream commit 8f220664570e755946db1282f48e07f26e1f2cb4 ]

commit 834b90519925 ("misc: pci_endpoint_test: Add support for
PCI_ENDPOINT_TEST regs to be mapped to any BAR") while adding
test_reg_bar in order to map PCI_ENDPOINT_TEST regs to be mapped to any
BAR failed to update test_reg_bar in pci_endpoint_test, resulting in
test_reg_bar having invalid value when used outside probe.

Fix it.

Fixes: 834b90519925 ("misc: pci_endpoint_test: Add support for PCI_ENDPOINT_TEST regs to be mapped to any BAR")
Signed-off-by: Kishon Vijay Abraham I 
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sasha Levin

genwqe: Prevent an integer overflow in the ioctl

2019-06-11T10:20:54+00:00

commit 110080cea0d0e4dfdb0b536e7f8a5633ead6a781 upstream.

There are a couple potential integer overflows here.

	round_up(m->size + (m->addr & ~PAGE_MASK), PAGE_SIZE);

The first thing is that the "m->size + (...)" addition could overflow,
and the second is that round_up() overflows to zero if the result is
within PAGE_SIZE of the type max.

In this code, the "m->size" variable is an u64 but we're saving the
result in "map_size" which is an unsigned long and genwqe_user_vmap()
takes an unsigned long as well.  So I have used ULONG_MAX as the upper
bound.  From a practical perspective unsigned long is fine/better than
trying to change all the types to u64.

Fixes: eaf4722d4645 ("GenWQE Character device and DDCB queue")
Signed-off-by: Dan Carpenter 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

lkdtm: Add tests for NULL pointer dereference

2019-04-20T07:16:04+00:00

[ Upstream commit 59a12205d3c32aee4c13ca36889fdf7cfed31126 ]

Introduce lkdtm tests for NULL pointer dereference: check access or exec
at NULL address, since these errors tend to be reported differently from
the general fault error text. For example from x86:

    pr_alert("BUG: unable to handle kernel %s at %px\n",
        address < PAGE_SIZE ? "NULL pointer dereference" : "paging request",
        (void *)address);

Signed-off-by: Christophe Leroy 
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin

lkdtm: Print real addresses

2019-04-20T07:16:03+00:00

[ Upstream commit 4c411157a42f122051ae3469bee0b5cabe89e139 ]

Today, when doing a lkdtm test before the readiness of the
random generator, (ptrval) is printed instead of the address
at which it perform the fault:

[ 1597.337030] lkdtm: Performing direct entry EXEC_USERSPACE
[ 1597.337142] lkdtm: attempting ok execution at (ptrval)
[ 1597.337398] lkdtm: attempting bad execution at (ptrval)
[ 1597.337460] kernel tried to execute user page (77858000) -exploit attempt? (uid: 0)
[ 1597.344769] Unable to handle kernel paging request for instruction fetch
[ 1597.351392] Faulting instruction address: 0x77858000
[ 1597.356312] Oops: Kernel access of bad area, sig: 11 [#1]

If the lkdtm test is done later on, it prints an hashed address.

In both cases this is pointless. The purpose of the test is to
ensure the kernel generates an Oops at the expected address,
so real addresses needs to be printed. This patch fixes that.

Signed-off-by: Christophe Leroy 
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin

cxl: Wrap iterations over afu slices inside 'afu_list_lock'

2019-03-23T19:10:03+00:00

commit edeb304f659792fb5bab90d7d6f3408b4c7301fb upstream.

Within cxl module, iteration over array 'adapter->afu' may be racy
at few points as it might be simultaneously read during an EEH and its
contents being set to NULL while driver is being unloaded or unbound
from the adapter. This might result in a NULL pointer to 'struct afu'
being de-referenced during an EEH thereby causing a kernel oops.

This patch fixes this by making sure that all access to the array
'adapter->afu' is wrapped within the context of spin-lock
'adapter->afu_list_lock'.

Fixes: 9e8df8a21963 ("cxl: EEH support")
Cc: stable@vger.kernel.org # v4.3+
Acked-by: Andrew Donnellan 
Acked-by: Frederic Barrat 
Acked-by: Christophe Lombard 
Signed-off-by: Vaibhav Jain 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

mei: bus: move hw module get/put to probe/release

2019-03-23T19:09:39+00:00

commit b5958faa34e2f99f3475ad89c52d98dfea079d33 upstream.

Fix unbalanced module reference counting during internal reset, which
prevents the drivers unloading.
Tracking mei_me/txe modules on mei client bus via
mei_cldev_enable/disable is error prone due to possible internal
reset flow, where clients are disconnected underneath.
Moving reference counting to probe and release of mei bus client
driver solves this issue in simplest way, as each client provides only
a single connection to a client bus driver.

Cc: 
Signed-off-by: Alexander Usyskin 
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman