ore: Fix out-of-bounds access in _ios_obj()

_ios_obj() is accessed by group_index not device_table index.

The oc->comps array is only a group_full of devices at a time
it is not like ore_comp_dev() which is indexed by a global
device_table index.

This did not BUG until now because exofs only uses a single
COMP for all devices. But with other FSs like PanFS this is
not true.

This bug was only in the write_path, all other users were
using it correctly

[This is a bug since 3.2 Kernel]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

diff --git a/fs/exofs/ore.c b/fs/exofs/ore.c
index 24a49d47e9354c00f0ebd2da6c92d3520e71332c..1585db1aa3651a3eb2fbe586156fd5bd270f5b82 100644 (file)
--- a/fs/exofs/ore.c
+++ b/fs/exofs/ore.c
@@ -837,11 +837,11 @@ static int _write_mirror(struct ore_io_state *ios, int cur_comp)
                                bio->bi_rw |= REQ_WRITE;
                        }
 
-                       osd_req_write(or, _ios_obj(ios, dev), per_dev->offset,
-                                     bio, per_dev->length);
+                       osd_req_write(or, _ios_obj(ios, cur_comp),
+                                     per_dev->offset, bio, per_dev->length);
                        ORE_DBGMSG("write(0x%llx) offset=0x%llx "
                                      "length=0x%llx dev=%d\n",
-                                    _LLU(_ios_obj(ios, dev)->id),
+                                    _LLU(_ios_obj(ios, cur_comp)->id),
                                     _LLU(per_dev->offset),
                                     _LLU(per_dev->length), dev);
                } else if (ios->kern_buff) {
@@ -853,20 +853,20 @@ static int _write_mirror(struct ore_io_state *ios, int cur_comp)
                               (ios->si.unit_off + ios->length >
                                ios->layout->stripe_unit));
 
-                       ret = osd_req_write_kern(or, _ios_obj(ios, per_dev->dev),
+                       ret = osd_req_write_kern(or, _ios_obj(ios, cur_comp),
                                                 per_dev->offset,
                                                 ios->kern_buff, ios->length);
                        if (unlikely(ret))
                                goto out;
                        ORE_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
                                      "length=0x%llx dev=%d\n",
-                                    _LLU(_ios_obj(ios, dev)->id),
+                                    _LLU(_ios_obj(ios, cur_comp)->id),
                                     _LLU(per_dev->offset),
                                     _LLU(ios->length), per_dev->dev);
                } else {
-                       osd_req_set_attributes(or, _ios_obj(ios, dev));
+                       osd_req_set_attributes(or, _ios_obj(ios, cur_comp));
                        ORE_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
-                                    _LLU(_ios_obj(ios, dev)->id),
+                                    _LLU(_ios_obj(ios, cur_comp)->id),
                                     ios->out_attr_len, dev);
                }