linux.git/kernel/dma, branch v6.6.39

dma-mapping: benchmark: avoid needless copy_to_user if benchmark fails

2024-07-11T10:49:20+00:00

[ Upstream commit f7c9ccaadffd13066353332c13d7e9bf73b8f92d ]

If do_map_benchmark() has failed, there is nothing useful to copy back
to userspace.

Suggested-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Fedor Pchelkin 
Acked-by: Robin Murphy 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

swiotlb: extend buffer pre-padding to alloc_align_mask if necessary

2024-06-21T12:38:46+00:00

commit af133562d5aff41fcdbe51f1a504ae04788b5fc0 upstream.

Allow a buffer pre-padding of up to alloc_align_mask, even if it requires
allocating additional IO TLB slots.

If the allocation alignment is bigger than IO_TLB_SIZE and min_align_mask
covers any non-zero bits in the original address between IO_TLB_SIZE and
alloc_align_mask, these bits are not preserved in the swiotlb buffer
address.

To fix this case, increase the allocation size and use a larger offset
within the allocated buffer. As a result, extra padding slots may be
allocated before the mapping start address.

Leave orig_addr in these padding slots initialized to INVALID_PHYS_ADDR.
These slots do not correspond to any CPU buffer, so attempts to sync the
data should be ignored.

The padding slots should be automatically released when the buffer is
unmapped. However, swiotlb_tbl_unmap_single() takes only the address of the
DMA buffer slot, not the first padding slot. Save the number of padding
slots in struct io_tlb_slot and use it to adjust the slot index in
swiotlb_release_slots(), so all allocated slots are properly freed.

Cc: stable@vger.kernel.org # v6.6+
Fixes: 2fd4fa5d3fb5 ("swiotlb: Fix alignment checks when both allocation and DMA masks are present")
Link: https://lore.kernel.org/linux-iommu/20240311210507.217daf8b@meshulam.tesarici.cz/
Signed-off-by: Petr Tesarik 
Reviewed-by: Michael Kelley 
Tested-by: Michael Kelley 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Fabio Estevam 
Signed-off-by: Greg Kroah-Hartman

swiotlb: Reinstate page-alignment for mappings >= PAGE_SIZE

2024-06-21T12:38:46+00:00

commit 14cebf689a78e8a1c041138af221ef6eac6bc7da upstream.

For swiotlb allocations >= PAGE_SIZE, the slab search historically
adjusted the stride to avoid checking unaligned slots. This had the
side-effect of aligning large mapping requests to PAGE_SIZE, but that
was broken by 0eee5ae10256 ("swiotlb: fix slot alignment checks").

Since this alignment could be relied upon drivers, reinstate PAGE_SIZE
alignment for swiotlb mappings >= PAGE_SIZE.

Cc: stable@vger.kernel.org # v6.6+
Reported-by: Michael Kelley 
Signed-off-by: Will Deacon 
Reviewed-by: Robin Murphy 
Reviewed-by: Petr Tesarik 
Tested-by: Nicolin Chen 
Tested-by: Michael Kelley 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Fabio Estevam 
Signed-off-by: Greg Kroah-Hartman

swiotlb: Enforce page alignment in swiotlb_alloc()

2024-06-21T12:38:46+00:00

commit 823353b7cf0ea9dfb09f5181d5fb2825d727200b upstream.

When allocating pages from a restricted DMA pool in swiotlb_alloc(),
the buffer address is blindly converted to a 'struct page *' that is
returned to the caller. In the unlikely event of an allocation bug,
page-unaligned addresses are not detected and slots can silently be
double-allocated.

Add a simple check of the buffer alignment in swiotlb_alloc() to make
debugging a little easier if something has gone wonky.

Cc: stable@vger.kernel.org # v6.6+
Signed-off-by: Will Deacon 
Reviewed-by: Michael Kelley 
Reviewed-by: Petr Tesarik 
Tested-by: Nicolin Chen 
Tested-by: Michael Kelley 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Fabio Estevam 
Signed-off-by: Greg Kroah-Hartman

dma-mapping: benchmark: handle NUMA_NO_NODE correctly

2024-06-12T09:12:52+00:00

[ Upstream commit e64746e74f717961250a155e14c156616fcd981f ]

cpumask_of_node() can be called for NUMA_NO_NODE inside do_map_benchmark()
resulting in the following sanitizer report:

UBSAN: array-index-out-of-bounds in ./arch/x86/include/asm/topology.h:72:28
index -1 is out of range for type 'cpumask [64][1]'
CPU: 1 PID: 990 Comm: dma_map_benchma Not tainted 6.9.0-rc6 #29
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
 
dump_stack_lvl (lib/dump_stack.c:117)
ubsan_epilogue (lib/ubsan.c:232)
__ubsan_handle_out_of_bounds (lib/ubsan.c:429)
cpumask_of_node (arch/x86/include/asm/topology.h:72) [inline]
do_map_benchmark (kernel/dma/map_benchmark.c:104)
map_benchmark_ioctl (kernel/dma/map_benchmark.c:246)
full_proxy_unlocked_ioctl (fs/debugfs/file.c:333)
__x64_sys_ioctl (fs/ioctl.c:890)
do_syscall_64 (arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Use cpumask_of_node() in place when binding a kernel thread to a cpuset
of a particular node.

Note that the provided node id is checked inside map_benchmark_ioctl().
It's just a NUMA_NO_NODE case which is not handled properly later.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 65789daa8087 ("dma-mapping: add benchmark support for streaming DMA APIs")
Signed-off-by: Fedor Pchelkin 
Acked-by: Barry Song 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

dma-mapping: benchmark: fix node id validation

2024-06-12T09:12:52+00:00

[ Upstream commit 1ff05e723f7ca30644b8ec3fb093f16312e408ad ]

While validating node ids in map_benchmark_ioctl(), node_possible() may
be provided with invalid argument outside of [0,MAX_NUMNODES-1] range
leading to:

BUG: KASAN: wild-memory-access in map_benchmark_ioctl (kernel/dma/map_benchmark.c:214)
Read of size 8 at addr 1fffffff8ccb6398 by task dma_map_benchma/971
CPU: 7 PID: 971 Comm: dma_map_benchma Not tainted 6.9.0-rc6 #37
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
 
dump_stack_lvl (lib/dump_stack.c:117)
kasan_report (mm/kasan/report.c:603)
kasan_check_range (mm/kasan/generic.c:189)
variable_test_bit (arch/x86/include/asm/bitops.h:227) [inline]
arch_test_bit (arch/x86/include/asm/bitops.h:239) [inline]
_test_bit at (include/asm-generic/bitops/instrumented-non-atomic.h:142) [inline]
node_state (include/linux/nodemask.h:423) [inline]
map_benchmark_ioctl (kernel/dma/map_benchmark.c:214)
full_proxy_unlocked_ioctl (fs/debugfs/file.c:333)
__x64_sys_ioctl (fs/ioctl.c:890)
do_syscall_64 (arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Compare node ids with sane bounds first. NUMA_NO_NODE is considered a
special valid case meaning that benchmarking kthreads won't be bound to a
cpuset of a given node.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 65789daa8087 ("dma-mapping: add benchmark support for streaming DMA APIs")
Signed-off-by: Fedor Pchelkin 
Reviewed-by: Robin Murphy 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

dma-mapping: benchmark: fix up kthread-related error handling

2024-06-12T09:12:52+00:00

[ Upstream commit bb9025f4432f8c158322cf2c04c2b492f23eb511 ]

kthread creation failure is invalidly handled inside do_map_benchmark().
The put_task_struct() calls on the error path are supposed to balance the
get_task_struct() calls which only happen after all the kthreads are
successfully created. Rollback using kthread_stop() for already created
kthreads in case of such failure.

In normal situation call kthread_stop_put() to gracefully stop kthreads
and put their task refcounts. This should be done for all started
kthreads.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 65789daa8087 ("dma-mapping: add benchmark support for streaming DMA APIs")
Suggested-by: Robin Murphy 
Signed-off-by: Fedor Pchelkin 
Reviewed-by: Robin Murphy 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y

2024-05-17T10:02:08+00:00

[ Upstream commit 75961ffb5cb3e5196f19cae7683f35cc88b50800 ]

Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction
with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following
crash when initialising the restricted pools at boot-time:

  | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
  | Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
  | pc : rmem_swiotlb_device_init+0xfc/0x1ec
  | lr : rmem_swiotlb_device_init+0xf0/0x1ec
  | Call trace:
  |  rmem_swiotlb_device_init+0xfc/0x1ec
  |  of_reserved_mem_device_init_by_idx+0x18c/0x238
  |  of_dma_configure_id+0x31c/0x33c
  |  platform_dma_configure+0x34/0x80

faddr2line reveals that the crash is in the list validation code:

  include/linux/list.h:83
  include/linux/rculist.h:79
  include/linux/rculist.h:106
  kernel/dma/swiotlb.c:306
  kernel/dma/swiotlb.c:1695

because add_mem_pool() is trying to list_add_rcu() to a NULL
'mem->pools'.

Fix the crash by initialising the 'mem->pools' list_head in
rmem_swiotlb_device_init() before calling add_mem_pool().

Reported-by: Nikita Ioffe 
Tested-by: Nikita Ioffe 
Fixes: 1aaa736815eb ("swiotlb: allocate a new memory pool when existing pools are full")
Signed-off-by: Will Deacon 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

dma-direct: Leak pages on dma_set_decrypted() failure

2024-04-13T11:07:32+00:00

[ Upstream commit b9fa16949d18e06bdf728a560f5c8af56d2bdcaf ]

On TDX it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.

DMA could free decrypted/shared pages if dma_set_decrypted() fails. This
should be a rare case. Just leak the pages in this case instead of
freeing them.

Signed-off-by: Rick Edgecombe 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

swiotlb: Fix alignment checks when both allocation and DMA masks are present

2024-04-03T13:28:51+00:00

[ Upstream commit 51b30ecb73b481d5fac6ccf2ecb4a309c9ee3310 ]

Nicolin reports that swiotlb buffer allocations fail for an NVME device
behind an IOMMU using 64KiB pages. This is because we end up with a
minimum allocation alignment of 64KiB (for the IOMMU to map the buffer
safely) but a minimum DMA alignment mask corresponding to a 4KiB NVME
page (i.e. preserving the 4KiB page offset from the original allocation).
If the original address is not 4KiB-aligned, the allocation will fail
because swiotlb_search_pool_area() erroneously compares these unmasked
bits with the 64KiB-aligned candidate allocation.

Tweak swiotlb_search_pool_area() so that the DMA alignment mask is
reduced based on the required alignment of the allocation.

Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers")
Link: https://lore.kernel.org/r/cover.1707851466.git.nicolinc@nvidia.com
Reported-by: Nicolin Chen 
Signed-off-by: Will Deacon 
Reviewed-by: Michael Kelley 
Tested-by: Nicolin Chen 
Tested-by: Michael Kelley 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Sasha Levin