diff options
Diffstat (limited to 'drivers/infiniband/ulp/isert/ib_isert.c')
| -rw-r--r-- | drivers/infiniband/ulp/isert/ib_isert.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c index 4691845bf815..9e050d034005 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -1332,6 +1332,21 @@ isert_recv_done(struct ib_cq *cq, struct ib_wc *wc) ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr, ISER_RX_SIZE, DMA_FROM_DEVICE); + /* + * The data segment length declared in the BHS is attacker controlled + * and is used further down to read that many bytes out of the fixed + * size receive descriptor, so it has to be checked against the number + * of bytes that were actually received. Comparing without subtracting + * also rejects PDUs shorter than the iSER and iSCSI headers, which + * would otherwise be parsed out of stale descriptor contents. + */ + if (unlikely(wc->byte_len < ISER_HEADERS_LEN + ntoh24(hdr->dlength))) { + isert_err("PDU declares %u data bytes but only %u bytes were received\n", + ntoh24(hdr->dlength), wc->byte_len); + iscsit_cause_connection_reinstatement(isert_conn->conn, 0); + return; + } + isert_dbg("DMA: 0x%llx, iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n", rx_desc->dma_addr, hdr->opcode, hdr->itt, hdr->flags, (int)(wc->byte_len - ISER_HEADERS_LEN)); |