[SCSI] mpt2sas: Added sanity check for cb_idx and smid access.

Sometime it is seen that controller
firmware returns an invalid system message id (smid).

the oops is occurring becuase mpt_callbacks pointer is referenced to
either null or invalid virtual address.  this is due to cb_idx set
incorrectly from routine _base_get_cb_idx.  the cb_idx was set incorrectly
becuase there is no check to make sure smid is less than maxiumum
anticapted smid.   to fix this issue, we add a check in
_base_get_cb_idx to make sure smid is not greater than
ioc->hba_queue_depth.   in addition, a similar check was added to make
sure the reply address was less than the largest anticapated address.

Newer firmware has sovled this issue, however it good to have this sanity
check.

Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

2 files changed, 9 insertions, 1 deletions

diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 12faf64f91b0..d1c53455c063 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -758,7 +758,7 @@ _base_get_cb_idx(struct MPT2SAS_ADAPTER *ioc, u16 smid)
                 if (smid < ioc->internal_smid) {
                         i = smid - ioc->hi_priority_smid;
                         cb_idx = ioc->hpr_lookup[i].cb_idx;
-                } else {
+                } else if (smid <= ioc->hba_queue_depth)  {
                         i = smid - ioc->internal_smid;
                         cb_idx = ioc->internal_lookup[i].cb_idx;
                 }
@@ -848,6 +848,7 @@ _base_interrupt(int irq, void *bus_id)
                 return IRQ_NONE;
 
         completed_cmds = 0;
+        cb_idx = 0xFF;
         do {
                 rd.word = rpf->Words;
                 if (rd.u.low == UINT_MAX || rd.u.high == UINT_MAX)
@@ -860,6 +861,9 @@ _base_interrupt(int irq, void *bus_id)
                     MPI2_RPY_DESCRIPT_FLAGS_ADDRESS_REPLY) {
                         reply = le32_to_cpu
                                 (rpf->AddressReply.ReplyFrameAddress);
+                        if (reply > ioc->reply_dma_max_address ||
+                            reply < ioc->reply_dma_min_address)
+                                reply = 0;
                 } else if (request_desript_type ==
                     MPI2_RPY_DESCRIPT_FLAGS_TARGET_COMMAND_BUFFER)
                         goto next;
@@ -2221,6 +2225,8 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
                     ioc->name);
                 goto out;
         }
+        ioc->reply_dma_min_address = (u32)(ioc->reply_dma);
+        ioc->reply_dma_max_address = (u32)(ioc->reply_dma) + sz;
         dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "reply pool(0x%p): depth"
             "(%d), frame_size(%d), pool_size(%d kB)\n", ioc->name, ioc->reply,
             ioc->reply_free_queue_depth, ioc->reply_sz, sz/1024));
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index 0b15a8bdebfc..63f7a196f42d 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -737,6 +737,8 @@ struct MPT2SAS_ADAPTER {
         u16             reply_sz;
         u8              *reply;
         dma_addr_t      reply_dma;
+        u32             reply_dma_max_address;
+        u32             reply_dma_min_address;
         struct dma_pool *reply_dma_pool;
 
         /* reply free queue */