From 03e4383c7ce36ac400489c8fe84724470a8251e9 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 7 Feb 2022 22:12:31 -0800 Subject: [PATCH] scsi: ibmvscsis: Silence -Warray-bounds warning Instead of doing a cast to storage that is too small, add a union for the high 64 bits. Silences the warnings under -Warray-bounds: drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c: In function 'ibmvscsis_send_messages': drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:1934:44: error: array subscript 'struct viosrp_crq[0]' is partly outside array bounds of 'u64[1]' {aka 'long long unsigned int[1]'} [-Werror=array-bounds] 1934 | crq->valid = VALID_CMD_RESP_EL; | ^~ drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:1875:13: note: while referencing 'msg_hi' 1875 | u64 msg_hi = 0; | ^~~~~~ There is no change to the resulting binary instructions. Link: https://lore.kernel.org/lkml/20220125142430.75c3160e@canb.auug.org.au Link: https://lore.kernel.org/r/20220208061231.3429486-1-keescook@chromium.org Cc: Michael Cyr Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: Tyrel Datwyler Cc: linux-scsi@vger.kernel.org Cc: target-devel@vger.kernel.org Reported-by: Stephen Rothwell Reviewed-by: Tyrel Datwyler Signed-off-by: Kees Cook Signed-off-by: Martin K. Petersen --- drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c | 9 +++------ include/scsi/viosrp.h | 17 +++++++++++------ 2 files changed, 14 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c index 61f06f6885a5..80238e6a3c98 100644 --- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c +++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c @@ -1872,11 +1872,8 @@ static void srp_snd_msg_failed(struct scsi_info *vscsi, long rc) */ static void ibmvscsis_send_messages(struct scsi_info *vscsi) { - u64 msg_hi = 0; - /* note do not attempt to access the IU_data_ptr with this pointer - * it is not valid - */ - struct viosrp_crq *crq = (struct viosrp_crq *)&msg_hi; + struct viosrp_crq empty_crq = { }; + struct viosrp_crq *crq = &empty_crq; struct ibmvscsis_cmd *cmd, *nxt; long rc = ADAPT_SUCCESS; bool retry = false; @@ -1940,7 +1937,7 @@ static void ibmvscsis_send_messages(struct scsi_info *vscsi) crq->IU_length = cpu_to_be16(cmd->rsp.len); rc = h_send_crq(vscsi->dma_dev->unit_address, - be64_to_cpu(msg_hi), + be64_to_cpu(crq->high), be64_to_cpu(cmd->rsp.tag)); dev_dbg(&vscsi->dev, "send_messages: cmd %p, tag 0x%llx, rc %ld\n", diff --git a/include/scsi/viosrp.h b/include/scsi/viosrp.h index c978133c83e3..6c5559d2b285 100644 --- a/include/scsi/viosrp.h +++ b/include/scsi/viosrp.h @@ -70,12 +70,17 @@ enum viosrp_crq_status { }; struct viosrp_crq { - u8 valid; /* used by RPA */ - u8 format; /* SCSI vs out-of-band */ - u8 reserved; - u8 status; /* non-scsi failure? (e.g. DMA failure) */ - __be16 timeout; /* in seconds */ - __be16 IU_length; /* in bytes */ + union { + __be64 high; /* High 64 bits */ + struct { + u8 valid; /* used by RPA */ + u8 format; /* SCSI vs out-of-band */ + u8 reserved; + u8 status; /* non-scsi failure? (e.g. DMA failure) */ + __be16 timeout; /* in seconds */ + __be16 IU_length; /* in bytes */ + }; + }; __be64 IU_data_ptr; /* the TCE for transferring data */ };