[ 12/55] SCSI: mpt2sas: Fix for panic happening because of improper memory allocation

From: Greg KH
Date: Sat May 26 2012 - 21:55:39 EST


3.0-stable review patch. If anyone has any objections, please let me know.

------------------

From: "nagalakshmi.nandigama@xxxxxxx" <nagalakshmi.nandigama@xxxxxxx>

commit e42fafc25fa86c61824e8d4c5e7582316415d24f upstream.

The ioc->pfacts member in the IOC structure is getting set to zero
following a call to _base_get_ioc_facts due to the memset in that routine.
So if the ioc->pfacts was read after a host reset, there would be a NULL
pointer dereference. The routine _base_get_ioc_facts is called from context
of host reset. The problem in _base_get_ioc_facts is the size of
Mpi2IOCFactsReply is 64, whereas the sizeof "struct mpt2sas_facts" is 60,
so there is a four byte overflow resulting from the memset.

Also, there is memset in _base_get_port_facts using the incorrect structure,
it should be "struct mpt2sas_port_facts" instead of Mpi2PortFactsReply.

Signed-off-by: Nagalakshmi Nandigama <nagalakshmi.nandigama@xxxxxxx>
Signed-off-by: James Bottomley <JBottomley@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/scsi/mpt2sas/mpt2sas_base.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -3056,7 +3056,7 @@ _base_get_port_facts(struct MPT2SAS_ADAP
}

pfacts = &ioc->pfacts[port];
- memset(pfacts, 0, sizeof(Mpi2PortFactsReply_t));
+ memset(pfacts, 0, sizeof(struct mpt2sas_port_facts));
pfacts->PortNumber = mpi_reply.PortNumber;
pfacts->VP_ID = mpi_reply.VP_ID;
pfacts->VF_ID = mpi_reply.VF_ID;
@@ -3098,7 +3098,7 @@ _base_get_ioc_facts(struct MPT2SAS_ADAPT
}

facts = &ioc->facts;
- memset(facts, 0, sizeof(Mpi2IOCFactsReply_t));
+ memset(facts, 0, sizeof(struct mpt2sas_facts));
facts->MsgVersion = le16_to_cpu(mpi_reply.MsgVersion);
facts->HeaderVersion = le16_to_cpu(mpi_reply.HeaderVersion);
facts->VP_ID = mpi_reply.VP_ID;
@@ -3779,7 +3779,7 @@ mpt2sas_base_attach(struct MPT2SAS_ADAPT
goto out_free_resources;

ioc->pfacts = kcalloc(ioc->facts.NumberOfPorts,
- sizeof(Mpi2PortFactsReply_t), GFP_KERNEL);
+ sizeof(struct mpt2sas_port_facts), GFP_KERNEL);
if (!ioc->pfacts) {
r = -ENOMEM;
goto out_free_resources;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/