From 568778f5572afd5b30984edd2a4a2c96df8b2b16 Mon Sep 17 00:00:00 2001 From: Len Baker Date: Sat, 25 Sep 2021 13:42:05 +0200 Subject: scsi: advansys: Prefer struct_size() over open-coded arithmetic 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. Use the struct_size() helper to do the arithmetic instead of the argument "size + count * size" in the kzalloc() function. This code was detected with the help of Coccinelle and audited and fixed manually. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Link: https://lore.kernel.org/r/20210925114205.11377-1-len.baker@gmx.com Reviewed-by: Gustavo A. R. Silva Signed-off-by: Len Baker Signed-off-by: Martin K. Petersen --- drivers/scsi/advansys.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/scsi/advansys.c') diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c index ffb391967573..e341b3372482 100644 --- a/drivers/scsi/advansys.c +++ b/drivers/scsi/advansys.c @@ -7477,8 +7477,8 @@ 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); + asc_sg_head = kzalloc(struct_size(asc_sg_head, sg_list, use_sg), + GFP_ATOMIC); if (!asc_sg_head) { scsi_dma_unmap(scp); set_host_byte(scp, DID_SOFT_ERROR); -- cgit