linux-toradex.git/drivers/vfio, branch v4.4.76

vfio/spapr: fail tce_iommu_attach_group() when iommu_data is null

2017-07-05T12:37:19+00:00

[ Upstream commit bd00fdf198e2da475a2f4265a83686ab42d998a8 ]

The recently added mediated VFIO driver doesn't know about powerpc iommu.
It thus doesn't register a struct iommu_table_group in the iommu group
upon device creation. The iommu_data pointer hence remains null.

This causes a kernel oops when userspace tries to set the iommu type of a
container associated with a mediated device to VFIO_SPAPR_TCE_v2_IOMMU.

[   82.585440] mtty mtty: MDEV: Registered
[   87.655522] iommu: Adding device 83b8f4f2-509f-382f-3c1e-e6bfe0fa1001 to group 10
[   87.655527] vfio_mdev 83b8f4f2-509f-382f-3c1e-e6bfe0fa1001: MDEV: group_id = 10
[  116.297184] Unable to handle kernel paging request for data at address 0x00000030
[  116.297389] Faulting instruction address: 0xd000000007870524
[  116.297465] Oops: Kernel access of bad area, sig: 11 [#1]
[  116.297611] SMP NR_CPUS=2048
[  116.297611] NUMA
[  116.297627] PowerNV
...
[  116.297954] CPU: 33 PID: 7067 Comm: qemu-system-ppc Not tainted 4.10.0-rc5-mdev-test #8
[  116.297993] task: c000000e7718b680 task.stack: c000000e77214000
[  116.298025] NIP: d000000007870524 LR: d000000007870518 CTR: 0000000000000000
[  116.298064] REGS: c000000e77217990 TRAP: 0300   Not tainted  (4.10.0-rc5-mdev-test)
[  116.298103] MSR: 9000000000009033 
[  116.298107]   CR: 84004444  XER: 00000000
[  116.298154] CFAR: c00000000000888c DAR: 0000000000000030 DSISR: 40000000 SOFTE: 1
               GPR00: d000000007870518 c000000e77217c10 d00000000787b0ed c000000eed2103c0
               GPR04: 0000000000000000 0000000000000000 c000000eed2103e0 0000000f24320000
               GPR08: 0000000000000104 0000000000000001 0000000000000000 d0000000078729b0
               GPR12: c00000000025b7e0 c00000000fe08400 0000000000000001 000001002d31d100
               GPR16: 000001002c22c850 00003ffff315c750 0000000043145680 0000000043141bc0
               GPR20: ffffffffffffffed fffffffffffff000 0000000020003b65 d000000007706018
               GPR24: c000000f16cf0d98 d000000007706000 c000000003f42980 c000000003f42980
               GPR28: c000000f1575ac00 c000000003f429c8 0000000000000000 c000000eed2103c0
[  116.298504] NIP [d000000007870524] tce_iommu_attach_group+0x10c/0x360 [vfio_iommu_spapr_tce]
[  116.298555] LR [d000000007870518] tce_iommu_attach_group+0x100/0x360 [vfio_iommu_spapr_tce]
[  116.298601] Call Trace:
[  116.298610] [c000000e77217c10] [d000000007870518] tce_iommu_attach_group+0x100/0x360 [vfio_iommu_spapr_tce] (unreliable)
[  116.298671] [c000000e77217cb0] [d0000000077033a0] vfio_fops_unl_ioctl+0x278/0x3e0 [vfio]
[  116.298713] [c000000e77217d40] [c0000000002a3ebc] do_vfs_ioctl+0xcc/0x8b0
[  116.298745] [c000000e77217de0] [c0000000002a4700] SyS_ioctl+0x60/0xc0
[  116.298782] [c000000e77217e30] [c00000000000b220] system_call+0x38/0xfc
[  116.298812] Instruction dump:
[  116.298828] 7d3f4b78 409effc8 3d220000 e9298020 3c800140 38a00018 608480c0 e8690028
[  116.298869] 4800249d e8410018 7c7f1b79 41820230  2fa90000 419e0114 e9090020
[  116.298914] ---[ end trace 1e10b0ced08b9120 ]---

This patch fixes the oops.

Reported-by: Vaibhav Jain 
Signed-off-by: Greg Kurz 
Signed-off-by: Alex Williamson 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

vfio/type1: Remove locked page accounting workqueue

2017-05-20T12:27:00+00:00

commit 0cfef2b7410b64d7a430947e0b533314c4f97153 upstream.

If the mmap_sem is contented then the vfio type1 IOMMU backend will
defer locked page accounting updates to a workqueue task.  This has a
few problems and depending on which side the user tries to play, they
might be over-penalized for unmaps that haven't yet been accounted or
race the workqueue to enter more mappings than they're allowed.  The
original intent of this workqueue mechanism seems to be focused on
reducing latency through the ioctl, but we cannot do so at the cost
of correctness.  Remove this workqueue mechanism and update the
callers to allow for failure.  We can also now recheck the limit under
write lock to make sure we don't exceed it.

vfio_pin_pages_remote() also now necessarily includes an unwind path
which we can jump to directly if the consecutive page pinning finds
that we're exceeding the user's memory limits.  This avoids the
current lazy approach which does accounting and mapping up to the
fault, only to return an error on the next iteration to unwind the
entire vfio_dma.

Cc: stable@vger.kernel.org
Reviewed-by: Peter Xu 
Reviewed-by: Kirti Wankhede 
Signed-off-by: Alex Williamson 
Signed-off-by: Greg Kroah-Hartman

vfio/pci: Fix integer overflows, bitmask check

2017-04-30T03:49:29+00:00

commit 05692d7005a364add85c6e25a6c4447ce08f913a upstream.

The VFIO_DEVICE_SET_IRQS ioctl did not sufficiently sanitize
user-supplied integers, potentially allowing memory corruption. This
patch adds appropriate integer overflow checks, checks the range bounds
for VFIO_IRQ_SET_DATA_NONE, and also verifies that only single element
in the VFIO_IRQ_SET_DATA_TYPE_MASK bitmask is set.
VFIO_IRQ_SET_ACTION_TYPE_MASK is already correctly checked later in
vfio_pci_set_irqs_ioctl().

Furthermore, a kzalloc is changed to a kcalloc because the use of a
kzalloc with an integer multiplication allowed an integer overflow
condition to be reached without this patch. kcalloc checks for overflow
and should prevent a similar occurrence.

Signed-off-by: Vlad Tsyrklevich 
Signed-off-by: Alex Williamson 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

vfio/spapr: Postpone allocation of userspace version of TCE table

2017-03-30T07:35:20+00:00

From: Alexey Kardashevskiy 

[ Upstream commit 39701e56f5f16ea0cf8fc9e8472e645f8de91d23 ]

The iommu_table struct manages a hardware TCE table and a vmalloc'd
table with corresponding userspace addresses. Both are allocated when
the default DMA window is created and this happens when the very first
group is attached to a container.

As we are going to allow the userspace to configure container in one
memory context and pas container fd to another, we have to postpones
such allocations till a container fd is passed to the destination
user process so we would account locked memory limit against the actual
container user constrainsts.

This postpones the it_userspace array allocation till it is used first
time for mapping. The unmapping patch already checks if the array is
allocated.

Signed-off-by: Alexey Kardashevskiy 
Reviewed-by: David Gibson 
Acked-by: Alex Williamson 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sumit Semwal 
Signed-off-by: Greg Kroah-Hartman

vfio/pci: Fix NULL pointer oops in error interrupt setup handling

2016-09-07T06:32:37+00:00

commit c8952a707556e04374d7b2fdb3a079d63ddf6f2f upstream.

There are multiple cases in vfio_pci_set_ctx_trigger_single() where
we assume we can safely read from our data pointer without actually
checking whether the user has passed any data via the count field.
VFIO_IRQ_SET_DATA_NONE in particular is entirely broken since we
attempt to pull an int32_t file descriptor out before even checking
the data type.  The other data types assume the data pointer contains
one element of their type as well.

In part this is good news because we were previously restricted from
doing much sanitization of parameters because it was missed in the
past and we didn't want to break existing users.  Clearly DATA_NONE
is completely broken, so it must not have any users and we can fix
it up completely.  For DATA_BOOL and DATA_EVENTFD, we'll just
protect ourselves, returning error when count is zero since we
previously would have oopsed.

Signed-off-by: Alex Williamson 
Reported-by: Chris Thompson 
Reviewed-by: Eric Auger 
Signed-off-by: Greg Kroah-Hartman

vfio: fix ioctl error handling

2016-03-09T23:34:50+00:00

commit 8160c4e455820d5008a1116d2dca35f0363bb062 upstream.

Calling return copy_to_user(...) in an ioctl will not
do the right thing if there's a pagefault:
copy_to_user returns the number of bytes not copied
in this case.

Fix up vfio to do
	return copy_to_user(...)) ?
		-EFAULT : 0;

everywhere.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Alex Williamson 
Signed-off-by: Greg Kroah-Hartman

Revert: "vfio: Include No-IOMMU mode"

2015-12-04T15:38:42+00:00

Revert commit 033291eccbdb ("vfio: Include No-IOMMU mode") due to lack
of a user.  This was originally intended to fill a need for the DPDK
driver, but uptake has been slow so rather than support an unproven
kernel interface revert it and revisit when userspace catches up.

Signed-off-by: Alex Williamson

vfio: fix a warning message

2015-11-21T13:55:58+00:00

The first argument to the WARN() macro has to be a condition.  I'm sort
of disappointed that this code doesn't generate a compiler warning.  I
guess -Wformat-extra-args doesn't work in the kernel.

Signed-off-by: Dan Carpenter 
Signed-off-by: Alex Williamson

vfio: platform: remove needless stack usage

2015-11-20T16:00:10+00:00

request_module already takes format strings, so no need to duplicate
the effort.

Signed-off-by: Kees Cook 
Signed-off-by: Alex Williamson

vfio-pci: constify pci_error_handlers structures

2015-11-19T23:53:07+00:00

This pci_error_handlers structure is never modified, like all the other
pci_error_handlers structures, so declare it as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall 
Signed-off-by: Alex Williamson