Skip to contentSkip to conversation

FAILED: patch "[PATCH] scsi: qla2xxx: Fix mem access after free" failed to apply to 5.4-stable tree

PATCH [email protected] 1 participant 1 message Jul 21, 2023

Subsystems (3)
lore
Share & tools
lore

[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x b843adde8d490934d042fbe9e3e46697cb3a64d2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023072125-educator-unroll-251d@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

b843adde8d49 ("scsi: qla2xxx: Fix mem access after free")
d3affdeb400f ("scsi: qla2xxx: Synchronize the IOCB count to be in order") c39587bc0aba ("scsi: qla2xxx: Fix crash due to stale SRB access around I/O timeouts") 5597616333ea ("scsi: qla2xxx: Stop using the SCSI pointer")
79e30b884a01 ("scsi: qla2xxx: Call scsi_done() directly")
e56b2234ab64 ("scsi: qla2xxx: Open-code qla2xxx_eh_target_reset()") 622299f16f33 ("scsi: qla2xxx: Simplify return value logic in qla2x00_get_sp_from_handle()") f45bca8c5052 ("scsi: qla2xxx: Fix double scsi_done for abort path")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b843adde8d490934d042fbe9e3e46697cb3a64d2 Mon Sep 17 00:00:00 2001
From: Quinn Tran <[email protected]>
Date: Fri, 28 Apr 2023 00:53:37 -0700
Subject: [PATCH] scsi: qla2xxx: Fix mem access after free

System crash, where driver is accessing scsi layer's memory (scsi_cmnd->device->host) to search for a well known internal pointer (vha). The scsi_cmnd was released back to upper layer which could be freed, but the driver is still accessing it.

7 [ffffa8e8d2c3f8d0] page_fault at ffffffff86c010fe
[exception RIP: __qla2x00_eh_wait_for_pending_commands+240]

  RIP: ffffffffc0642350  RSP: ffffa8e8d2c3f988  RFLAGS: 00010286
  RAX: 0000000000000165  RBX: 0000000000000002  RCX: 00000000000036d8
  RDX: 0000000000000000  RSI: ffff9c5c56535188  RDI: 0000000000000286
  RBP: ffff9c5bf7aa4a58   R8: ffff9c589aecdb70   R9: 00000000000003d1
  R10: 0000000000000001  R11: 0000000000380000 R12: ffff9c5c5392bc78
  R13: ffff9c57044ff5c0 R14: ffff9c56b5a3aa00  R15: 00000000000006db
  ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018

8 [ffffa8e8d2c3f9c8] qla2x00_eh_wait_for_pending_commands at ffffffffc0646dd5 [qla2xxx] 9 [ffffa8e8d2c3fa00] __qla2x00_async_tm_cmd at ffffffffc0658094 [qla2xxx]

Remove access of freed memory. Currently the driver was checking to see if scsi_done was called by seeing if the sp->type has changed. Instead, check to see if the command has left the oustanding_cmds[] array as sign of scsi_done was called.

drivers/scsi/qla2xxx/qla_isr.c +31 -7
index f3107508cf12..a07c010b0843 100644
@@ -1862,9 +1862,9 @@ qla2x00_process_completed_request(struct scsi_qla_host *vha,
 	}
 }
 
-srb_t *
-qla2x00_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
-    struct req_que *req, void *iocb)
+static srb_t *
+qla_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
+		       struct req_que *req, void *iocb, u16 *ret_index)
 {
 	struct qla_hw_data *ha = vha->hw;
 	sts_entry_t *pkt = iocb;
@@ -1899,12 +1899,25 @@ qla2x00_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
 		return NULL;
 	}
 
-	req->outstanding_cmds[index] = NULL;
-
+	*ret_index = index;
 	qla_put_fw_resources(sp->qpair, &sp->iores);
 	return sp;
 }
 
+srb_t *
+qla2x00_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
+			   struct req_que *req, void *iocb)
+{
+	uint16_t index;
+	srb_t *sp;
+
+	sp = qla_get_sp_from_handle(vha, func, req, iocb, &index);
+	if (sp)
+		req->outstanding_cmds[index] = NULL;
+
+	return sp;
+}
+
 static void
 qla2x00_mbx_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
     struct mbx_entry *mbx)
@@ -3237,13 +3250,13 @@ qla2x00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt)
 		return;
 	}
 
-	req->outstanding_cmds[handle] = NULL;
 	cp = GET_CMD_SP(sp);
 	if (cp == NULL) {
 		ql_dbg(ql_dbg_io, vha, 0x3018,
 		    "Command already returned (0x%x/%p).\n",
 		    sts->handle, sp);
 
+		req->outstanding_cmds[handle] = NULL;
 		return;
 	}
 
@@ -3514,6 +3527,9 @@ qla2x00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt)
 
 	if (rsp->status_srb == NULL)
 		sp->done(sp, res);
+
+	/* for io's, clearing of outstanding_cmds[handle] means scsi_done was called */
+	req->outstanding_cmds[handle] = NULL;
 }
 
 /**
@@ -3590,6 +3606,7 @@ qla2x00_error_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, sts_entry_t *pkt)
 	uint16_t que = MSW(pkt->handle);
 	struct req_que *req = NULL;
 	int res = DID_ERROR << 16;
+	u16 index;
 
 	ql_dbg(ql_dbg_async, vha, 0x502a,
 	    "iocb type %xh with error status %xh, handle %xh, rspq id %d\n",
@@ -3608,7 +3625,6 @@ qla2x00_error_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, sts_entry_t *pkt)
 
 	switch (pkt->entry_type) {
 	case NOTIFY_ACK_TYPE:
-	case STATUS_TYPE:
 	case STATUS_CONT_TYPE:
 	case LOGINOUT_PORT_IOCB_TYPE:
 	case CT_IOCB_TYPE:
@@ -3628,6 +3644,14 @@ qla2x00_error_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, sts_entry_t *pkt)
 	case CTIO_TYPE7:
 	case CTIO_CRC2:
 		return 1;
+	case STATUS_TYPE:
+		sp = qla_get_sp_from_handle(vha, func, req, pkt, &index);
+		if (sp) {
+			sp->done(sp, res);
+			req->outstanding_cmds[index] = NULL;
+			return 0;
+		}
+		break;
 	}
 fatal:
 	ql_log(ql_log_warn, vha, 0x5030,
drivers/scsi/qla2xxx/qla_os.c +64 -66

154 lines not on this page · raw message