On 9/23/24 12:26, Niall Meade wrote:
Addressed a specific overflow issue in the eth_dev_adjust_nb_desc() function where the uint16_t variable nb_desc would overflow when its value was greater than (2^16 - nb_align). This overflow caused nb_desc to incorrectly wrap around between 0 and nb_align-1, leading to the function setting nb_desc to nb_min instead of the expected nb_max.The resolution involves upcasting nb_desc to a uint32_t before the RTE_ALIGN_CEIL macro is applied. This change ensures that the subsequent call to RTE_ALIGN_FLOOR(nb_desc + (nb_align - 1), nb_align) does not result in an overflow, as it would when nb_desc is a uint16_t. By using a uint32_t for these operations, the correct behavior is maintained without the risk of overflow. Fixes: 0f67fc3baeb9 ("ethdev: add function to adjust number of descriptors") Signed-off-by: Niall Meade <[email protected]>
Thanks a lot for the fix. Reviewed-by: Andrew Rybchenko <[email protected]>
