From 036b465f39e6a8c3f15987fc3b4149c1ed39de42 Mon Sep 17 00:00:00 2001 From: Chad Dupuis Date: Thu, 7 Apr 2016 09:07:59 -0400 Subject: [PATCH] bnx2fc: Check sc_cmd device and host pointer before returning the command to the mid-layer. Orabug: 24011326 When we are in connection recovery and the internal command timer on a request pops, either the scsi_cmnd->device or scsi_cmnd->device->host back pointers may be NULL as the device that the command that the request was submitted on may have been subsequently reaped due to the connection recovery. This can cause one or both of the pointers above to be NULL and cause a system crash if we try to return the command to the midlayer. Instead, double check the pointers before the return to the midlayer so as to prevent the crash and let the upper layers finish the session recovery and rediscover the device. Signed-off-by: Chad Dupuis Reviewed-by: Johannes Thumshirn Signed-off-by: Martin K. Petersen Signed-off-by: Ethan Zhao --- drivers/scsi/bnx2fc/bnx2fc_io.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/scsi/bnx2fc/bnx2fc_io.c b/drivers/scsi/bnx2fc/bnx2fc_io.c index dfd058a62d64..2452f55ff343 100644 --- a/drivers/scsi/bnx2fc/bnx2fc_io.c +++ b/drivers/scsi/bnx2fc/bnx2fc_io.c @@ -179,12 +179,24 @@ static void bnx2fc_scsi_done(struct bnx2fc_cmd *io_req, int err_code) bnx2fc_unmap_sg_list(io_req); io_req->sc_cmd = NULL; + + /* Sanity checks before returning command to mid-layer */ if (!sc_cmd) { printk(KERN_ERR PFX "scsi_done - sc_cmd NULL. " "IO(0x%x) already cleaned up\n", io_req->xid); return; } + if (!sc_cmd->device) { + pr_err(PFX "0x%x: sc_cmd->device is NULL.\n", io_req->xid); + return; + } + if (!sc_cmd->device->host) { + pr_err(PFX "0x%x: sc_cmd->device->host is NULL.\n", + io_req->xid); + return; + } + sc_cmd->result = err_code << 16; BNX2FC_IO_DBG(io_req, "sc=%p, result=0x%x, retries=%d, allowed=%d\n", -- 2.50.1