scsi: lpfc: Revise lpfc_prep_embed_io routine with proper endian macro usages

On big endian architectures, it is possible to run into a memory out of
bounds pointer dereference when FCP targets are zoned.

In lpfc_prep_embed_io, the memcpy(ptr, fcp_cmnd, sgl->sge_len) is
referencing a little endian formatted sgl->sge_len value.  So, the memcpy
can cause big endian systems to crash.

Redefine the *sgl ptr as a struct sli4_sge_le to make it clear that we are
referring to a little endian formatted data structure.  And, update the
routine with proper le32_to_cpu macro usages.

Fixes: af20bb73ac25 ("scsi: lpfc: Add support for 32 byte CDBs")
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20240628172011.25921-8-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 8bfac9143314713c3e35ff70e6c683ea822d767f..88debef2fb6db0e4fdd7f56b6d6d778ebb3aec92 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -10579,10 +10579,11 @@ lpfc_prep_embed_io(struct lpfc_hba *phba, struct lpfc_io_buf *lpfc_cmd)
 {
        struct lpfc_iocbq *piocb = &lpfc_cmd->cur_iocbq;
        union lpfc_wqe128 *wqe = &lpfc_cmd->cur_iocbq.wqe;
-       struct sli4_sge *sgl;
+       struct sli4_sge_le *sgl;
+       u32 type_size;
 
        /* 128 byte wqe support here */
-       sgl = (struct sli4_sge *)lpfc_cmd->dma_sgl;
+       sgl = (struct sli4_sge_le *)lpfc_cmd->dma_sgl;
 
        if (phba->fcp_embed_io) {
                struct fcp_cmnd *fcp_cmnd;
@@ -10591,9 +10592,9 @@ lpfc_prep_embed_io(struct lpfc_hba *phba, struct lpfc_io_buf *lpfc_cmd)
                fcp_cmnd = lpfc_cmd->fcp_cmnd;
 
                /* Word 0-2 - FCP_CMND */
-               wqe->generic.bde.tus.f.bdeFlags =
-                       BUFF_TYPE_BDE_IMMED;
-               wqe->generic.bde.tus.f.bdeSize = sgl->sge_len;
+               type_size = le32_to_cpu(sgl->sge_len);
+               type_size |= ULP_BDE64_TYPE_BDE_IMMED;
+               wqe->generic.bde.tus.w = type_size;
                wqe->generic.bde.addrHigh = 0;
                wqe->generic.bde.addrLow =  72;  /* Word 18 */
 
@@ -10602,13 +10603,13 @@ lpfc_prep_embed_io(struct lpfc_hba *phba, struct lpfc_io_buf *lpfc_cmd)
 
                /* Word 18-29  FCP CMND Payload */
                ptr = &wqe->words[18];
-               memcpy(ptr, fcp_cmnd, sgl->sge_len);
+               lpfc_sli_pcimem_bcopy(fcp_cmnd, ptr, le32_to_cpu(sgl->sge_len));
        } else {
                /* Word 0-2 - Inline BDE */
                wqe->generic.bde.tus.f.bdeFlags =  BUFF_TYPE_BDE_64;
-               wqe->generic.bde.tus.f.bdeSize = sgl->sge_len;
-               wqe->generic.bde.addrHigh = sgl->addr_hi;
-               wqe->generic.bde.addrLow =  sgl->addr_lo;
+               wqe->generic.bde.tus.f.bdeSize = le32_to_cpu(sgl->sge_len);
+               wqe->generic.bde.addrHigh = le32_to_cpu(sgl->addr_hi);
+               wqe->generic.bde.addrLow = le32_to_cpu(sgl->addr_lo);
 
                /* Word 10 */
                bf_set(wqe_dbde, &wqe->generic.wqe_com, 1);