Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

bnx2x: Fix multiple UBSAN array-index-out-of-bounds

Fix UBSAN warnings that occur when using a system with 32 physical cpu cores or more, or when the user defines a number of Ethernet queues greater than or equal to FP_SB_MAX_E1x using the num_queues module parameter.

Currently there is a read/write out of bounds that occurs on the array "struct stats_query_entry query" present inside the "bnx2x_fw_stats_req" struct in "drivers/net/ethernet/broadcom/bnx2x/bnx2x.h". Looking at the definition of the "struct stats_query_entry query" array:

struct stats_query_entry query[FP_SB_MAX_E1x+ BNX2X_FIRST_QUEUE_QUERY_IDX];

FP_SB_MAX_E1x is defined as the maximum number of fast path interrupts and has a value of 16, while BNX2X_FIRST_QUEUE_QUERY_IDX has a value of 3 meaning the array has a total size of 19. Since accesses to "struct stats_query_entry query" are offset-ted by BNX2X_FIRST_QUEUE_QUERY_IDX, that means that the total number of Ethernet queues should not exceed FP_SB_MAX_E1x (16). However one of these queues is reserved for FCOE and thus the number of Ethernet queues should be set to [FP_SB_MAX_E1x -1] (15) if FCOE is enabled or [FP_SB_MAX_E1x] (16) if it is not.

This is also described in a comment in the source code in drivers/net/ethernet/broadcom/bnx2x/bnx2x.h just above the Macro definition of FP_SB_MAX_E1x. Below is the part of this explanation that it important for this patch

/* * The t…