net: ena: Fix use of uninitialized DMA address bits field
authorGal Pressman <pressmangal@gmail.com>
Thu, 26 Jul 2018 20:40:33 +0000 (23:40 +0300)
committerDavid S. Miller <davem@davemloft.net>
Fri, 27 Jul 2018 04:30:13 +0000 (21:30 -0700)
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>

No differences found