From f09318244c6cafd10aca741b9c01e0a2c362d43a Mon Sep 17 00:00:00 2001 From: Shin'ichiro Kawasaki Date: Sat, 23 Mar 2024 17:41:55 +0900 Subject: [PATCH] scsi: mpi3mr: Avoid memcpy field-spanning write WARNING [ Upstream commit 429846b4b6ce9853e0d803a2357bb2e55083adf0 ] When the "storcli2 show" command is executed for eHBA-9600, mpi3mr driver prints this WARNING message: memcpy: detected field-spanning write (size 128) of single field "bsg_reply_buf->reply_buf" at drivers/scsi/mpi3mr/mpi3mr_app.c:1658 (size 1) WARNING: CPU: 0 PID: 12760 at drivers/scsi/mpi3mr/mpi3mr_app.c:1658 mpi3mr_bsg_request+0x6b12/0x7f10 [mpi3mr] The cause of the WARN is 128 bytes memcpy to the 1 byte size array "__u8 replay_buf[1]" in the struct mpi3mr_bsg_in_reply_buf. The array is intended to be a flexible length array, so the WARN is a false positive. To suppress the WARN, remove the constant number '1' from the array declaration and clarify that it has flexible length. Also, adjust the memory allocation size to match the change. Suggested-by: Sathya Prakash Veerichetty Signed-off-by: Shin'ichiro Kawasaki Link: https://lore.kernel.org/r/20240323084155.166835-1-shinichiro.kawasaki@wdc.com Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/mpi3mr/mpi3mr_app.c | 2 +- include/uapi/scsi/scsi_bsg_mpi3mr.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/mpi3mr/mpi3mr_app.c b/drivers/scsi/mpi3mr/mpi3mr_app.c index 9dacbb8570c9..aa5b535e6662 100644 --- a/drivers/scsi/mpi3mr/mpi3mr_app.c +++ b/drivers/scsi/mpi3mr/mpi3mr_app.c @@ -1345,7 +1345,7 @@ static long mpi3mr_bsg_process_mpt_cmds(struct bsg_job *job, unsigned int *reply if ((mpirep_offset != 0xFF) && drv_bufs[mpirep_offset].bsg_buf_len) { drv_buf_iter = &drv_bufs[mpirep_offset]; - drv_buf_iter->kern_buf_len = (sizeof(*bsg_reply_buf) - 1 + + drv_buf_iter->kern_buf_len = (sizeof(*bsg_reply_buf) + mrioc->reply_sz); bsg_reply_buf = kzalloc(drv_buf_iter->kern_buf_len, GFP_KERNEL); diff --git a/include/uapi/scsi/scsi_bsg_mpi3mr.h b/include/uapi/scsi/scsi_bsg_mpi3mr.h index 907d345f04f9..353183e863e4 100644 --- a/include/uapi/scsi/scsi_bsg_mpi3mr.h +++ b/include/uapi/scsi/scsi_bsg_mpi3mr.h @@ -382,7 +382,7 @@ struct mpi3mr_bsg_in_reply_buf { __u8 mpi_reply_type; __u8 rsvd1; __u16 rsvd2; - __u8 reply_buf[1]; + __u8 reply_buf[]; }; /**