Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

net: ena: Fix use of uninitialized DMA address bits field

UBSAN triggers the following undefined behaviour warnings:
[...]
[ 13.236124] UBSAN: Undefined behaviour in drivers/net/ethernet/amazon/ena/ena_eth_com.c:468:22
[ 13.240043] shift exponent 64 is too large for 64-bit type 'long long unsigned int'
[...]
[ 13.744769] UBSAN: Undefined behaviour in drivers/net/ethernet/amazon/ena/ena_eth_com.c:373:4
[ 13.748694] shift exponent 64 is too large for 64-bit type 'long long unsigned int'
[...]

When splitting the address to high and low, GENMASK_ULL is used to generate
a bitmask with dma_addr_bits field from io_sq (in ena_com_prepare_tx and
ena_com_add_single_rx_desc).
The problem is that dma_addr_bits is not initialized with a proper value
(besides being cleared in ena_com_create_io_queue).
Assign dma_addr_bits the correct value that is stored in ena_dev when
initializing the SQ.

Fixes: 1738cd3ed342 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Gal Pressman <pressmangal@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

authored by

Gal Pressman and committed by
David S. Miller
101f0cd4 9e630bcb

+1
+1
drivers/net/ethernet/amazon/ena/ena_com.c
··· 333 333 334 334 memset(&io_sq->desc_addr, 0x0, sizeof(io_sq->desc_addr)); 335 335 336 + io_sq->dma_addr_bits = ena_dev->dma_addr_bits; 336 337 io_sq->desc_entry_size = 337 338 (io_sq->direction == ENA_COM_IO_QUEUE_DIRECTION_TX) ? 338 339 sizeof(struct ena_eth_io_tx_desc) :