diff options
| author | scameron@beardog.cce.hp.com <scameron@beardog.cce.hp.com> | 2014-04-14 14:01:09 -0500 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2014-04-21 07:56:53 -0700 |
| commit | 67c99a72e3006e4276e91d7282a3d6734fc77a0b (patch) | |
| tree | 09ae42238805bdbc9f7f555187c40cfccb561685 /drivers/scsi/hpsa.c | |
| parent | c9eaa447e77efe77b7fa4c953bd62de8297fd6c5 (diff) | |
| download | linux-67c99a72e3006e4276e91d7282a3d6734fc77a0b.tar.bz2 | |
[SCSI] hpsa: fix NULL dereference in hpsa_put_ctlr_into_performant_mode()
Initialize local variable trans_support before it is used rather
than after. It is supposed to contain the value of a register on the
controller containing bits that describe which transport modes the
controller supports (e.g. "performant", "ioaccel1", "ioaccel2"). A
NULL pointer dereference will almost certainly occur if trans_support
is not initialized at the right point. If for example the uninitialized
trans_support value does not have the bit set for ioaccel2 support when it
should be, then ioaccel2_alloc_cmds_and_bft() will not get called as it
should be and the h->ioaccel2_blockFetchTable array will remain NULL
instead of being allocated. Too late, trans_support finally gets
initialized with the correct value with ioaccel2 mode bit set,
which later causes calc_bucket_map() to be called to fill in
h->ioaccel2_blockFetchTable[]. However h->ioaccel2_blockFetchTable
is NULL because it didn't get allocated because earlier trans_support
wasn't initialized at the right point.
Fixes: e1f7de0cdd68d246d7008241cd9e443a54f880a8
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Reported-by: Baoquan He <bhe@redhat.com>
Tested-by: Baoquan He <bhe@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/hpsa.c')
| -rw-r--r-- | drivers/scsi/hpsa.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 8cf4a0c69baf..9a6e4a2cd072 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -7463,6 +7463,10 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) if (hpsa_simple_mode) return; + trans_support = readl(&(h->cfgtable->TransportSupport)); + if (!(trans_support & PERFORMANT_MODE)) + return; + /* Check for I/O accelerator mode support */ if (trans_support & CFGTBL_Trans_io_accel1) { transMethod |= CFGTBL_Trans_io_accel1 | @@ -7479,10 +7483,6 @@ static void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) } /* TODO, check that this next line h->nreply_queues is correct */ - trans_support = readl(&(h->cfgtable->TransportSupport)); - if (!(trans_support & PERFORMANT_MODE)) - return; - h->nreply_queues = h->msix_vector > 0 ? h->msix_vector : 1; hpsa_get_max_perf_mode_cmds(h); /* Performant mode ring buffer and supporting data structures */ |