As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, refactor the code a bit to use the struct_size() helper instead of the argument "size + count * size" in the kzalloc() function. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Signed-off-by: Len Baker <len.baker@xxxxxxx> --- drivers/scsi/advansys.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c index ffb391967573..fe882502e7bf 100644 --- a/drivers/scsi/advansys.c +++ b/drivers/scsi/advansys.c @@ -7465,6 +7465,7 @@ static int asc_build_req(struct asc_board *boardp, struct scsi_cmnd *scp, return ASC_BUSY; } else if (use_sg > 0) { int sgcnt; + size_t size; struct scatterlist *slp; struct asc_sg_head *asc_sg_head; @@ -7477,8 +7478,8 @@ static int asc_build_req(struct asc_board *boardp, struct scsi_cmnd *scp, return ASC_ERROR; } - asc_sg_head = kzalloc(sizeof(asc_scsi_q->sg_head) + - use_sg * sizeof(struct asc_sg_list), GFP_ATOMIC); + size = struct_size(asc_scsi_q->sg_head, sg_list, use_sg); + asc_sg_head = kzalloc(size, GFP_ATOMIC); if (!asc_sg_head) { scsi_dma_unmap(scp); set_host_byte(scp, DID_SOFT_ERROR); -- 2.25.1
