linux/drivers/vdpa
Christian Borntraeger 727e1f5698 vdpa/mlx5: Fix buffer length in create_direct_keys()
We have seen in our CI the following KASAN message:
BUG: KASAN: slab-out-of-bounds in cmd_exec+0x550/0xca0 [mlx5_core]
Read of size 272 at addr 0000000176795020 by task qemu-system-s39/82764
[...]
[<000011388ab3a7a0>] cmd_exec+0x550/0xca0 [mlx5_core]
[<000011388ab3b61c>] mlx5_cmd_exec_cb+0x25c/0x4f0 [mlx5_core]
[<000011388b21e82e>] mlx5_vdpa_exec_async_cmds+0x22e/0x5e0 [mlx5_vdpa]
[<000011388b21fd44>] create_direct_keys+0x954/0xef0 [mlx5_vdpa]
[...]
The buggy address is located 4128 bytes inside of
allocated 4384-byte region [0000000176794000, 0000000176795120)

So in essence we read 16 bytes beyond 4384-byte allocation.
create_direct_keys calculates the pointer and length for in and out
buffers.
The size calculation for in includes the entire structure
size (out + in + mtt[]) but the pointer passed to cmd_exec points only
to the 'in' field, skipping the 'out' field.

This causes mlx5_copy_to_msg() to read beyond the allocated buffer
by sizeof(out) bytes when copying command data.

Properly calculate the input size to match the pointer and allocation size.

Fixes: 0071b138d4 ("vdpa/mlx5: Create direct MKEYs in parallel")
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Tested-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20260706141537.3510294-1-borntraeger@linux.ibm.com>
2026-08-03 15:21:54 -04:00
..
alibaba vdpa: introduce map ops 2025-10-01 07:24:55 -04:00
ifcvf vdpa/ifcvf: handle dev_set_name() failure in ifcvf_vdpa_dev_add() 2026-06-10 02:14:02 -04:00
mlx5 vdpa/mlx5: Fix buffer length in create_direct_keys() 2026-08-03 15:21:54 -04:00
octeon_ep vdpa/octeon_ep: fix IRQ-to-ring mapping in interrupt handler 2026-06-10 02:17:00 -04:00
pds Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
solidrun Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
vdpa_sim vhost_iotlb: bound map allocation in add_range 2026-08-03 15:21:54 -04:00
vdpa_user vhost_iotlb: bound map allocation in add_range 2026-08-03 15:21:54 -04:00
virtio_pci Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
Kconfig vduse: switch to use virtio map API instead of DMA API 2025-10-01 07:24:55 -04:00
Makefile virtio: vdpa: vDPA driver for Marvell OCTEON DPU devices 2024-07-09 08:42:39 -04:00
vdpa.c Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00