5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nilesh Javali commit 7c4f3f50d83af4545efaa99b3d0d46fb8d52031e upstream. qla26xx_dport_diagnostics() streaming-maps the caller's result buffer with dma_map_single(). The bsg path passes &dd->buf from the __packed struct qla_dport_diag, where buf lands at a 2-byte offset and shares cachelines with the surrounding options/unused fields. Mapping such a misaligned sub-buffer violates the DMA API requirement that streaming buffers be cacheline aligned and not share a cacheline with other data, and can corrupt data on non-DMA-coherent architectures. Allocate a dedicated DMA-coherent buffer inside qla26xx_dport_diagnostics() for the mailbox command and copy the result back into the caller's buffer. This removes the streaming map of the misaligned sub-buffer entirely; the caller's buffer is now only a plain CPU buffer, so its packing no longer matters. Fixes: ec89146215d1 ("qla2xxx: Add bsg interface to support D_Port Diagnostics.") Cc: stable@vger.kernel.org Reported-by: Sashiko Signed-off-by: Nilesh Javali Link: https://patch.msgid.link/20260730155838.2119230-29-njavali@marvell.com Signed-off-by: Martin K. Petersen (Oracle) Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/qla2xxx/qla_mbx.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) --- a/drivers/scsi/qla2xxx/qla_mbx.c +++ b/drivers/scsi/qla2xxx/qla_mbx.c @@ -6357,6 +6357,7 @@ qla26xx_dport_diagnostics(scsi_qla_host_ mbx_cmd_t mc; mbx_cmd_t *mcp = &mc; dma_addr_t dd_dma; + void *dd; if (!IS_QLA83XX(vha->hw) && !IS_QLA27XX(vha->hw) && !IS_QLA28XX(vha->hw)) @@ -6365,15 +6366,12 @@ qla26xx_dport_diagnostics(scsi_qla_host_ ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x119f, "Entered %s.\n", __func__); - dd_dma = dma_map_single(&vha->hw->pdev->dev, - dd_buf, size, DMA_FROM_DEVICE); - if (dma_mapping_error(&vha->hw->pdev->dev, dd_dma)) { - ql_log(ql_log_warn, vha, 0x1194, "Failed to map dma buffer.\n"); + dd = dma_alloc_coherent(&vha->hw->pdev->dev, size, &dd_dma, GFP_KERNEL); + if (!dd) { + ql_log(ql_log_warn, vha, 0x1194, "Failed to allocate dma buffer.\n"); return QLA_MEMORY_ALLOC_FAILED; } - memset(dd_buf, 0, size); - mcp->mb[0] = MBC_DPORT_DIAGNOSTICS; mcp->mb[1] = options; mcp->mb[2] = MSW(LSD(dd_dma)); @@ -6395,8 +6393,9 @@ qla26xx_dport_diagnostics(scsi_qla_host_ "Done %s.\n", __func__); } - dma_unmap_single(&vha->hw->pdev->dev, dd_dma, - size, DMA_FROM_DEVICE); + memcpy(dd_buf, dd, size); + + dma_free_coherent(&vha->hw->pdev->dev, size, dd, dd_dma); return rval; }