4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Arnd Bergmann <arnd@xxxxxxxx>
commit 566e1ce22e04426fa52328b2adcdf1df49acd98e upstream.
We now get a helpful warning for code that calls copy_{from,to}_iter
without checking the return value, introduced by commit aa28de275a24
("iov_iter/hardening: move object size checks to inlined part").
drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c: In function 'kiblnd_send':
drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c:1643:2: error: ignoring return value of 'copy_from_iter', declared with attribute warn_unused_result [-Werror=unused-result]
drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c: In function 'kiblnd_recv':
drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c:1744:3: error: ignoring return value of 'copy_to_iter', declared with attribute warn_unused_result [-Werror=unused-result]
In case we get short copies here, we may get incorrect behavior.
I've added failure handling for both rx and tx now, returning
-EFAULT as expected.
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c | 19 +++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
--- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c
+++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c
@@ -1650,8 +1650,13 @@ kiblnd_send(lnet_ni_t *ni, void *private
ibmsg = tx->tx_msg;
ibmsg->ibm_u.immediate.ibim_hdr = *hdr;
- copy_from_iter(&ibmsg->ibm_u.immediate.ibim_payload, IBLND_MSG_SIZE,
- &from);
+ rc = copy_from_iter(&ibmsg->ibm_u.immediate.ibim_payload, payload_nob,
+ &from);
+ if (rc != payload_nob) {
+ kiblnd_pool_free_node(&tx->tx_pool->tpo_pool, &tx->tx_list);
+ return -EFAULT;
+ }
+
nob = offsetof(struct kib_immediate_msg, ibim_payload[payload_nob]);
kiblnd_init_tx_msg(ni, tx, IBLND_MSG_IMMEDIATE, nob);
@@ -1751,8 +1756,14 @@ kiblnd_recv(lnet_ni_t *ni, void *private
break;
}
- copy_to_iter(&rxmsg->ibm_u.immediate.ibim_payload,
- IBLND_MSG_SIZE, to);
+ rc = copy_to_iter(&rxmsg->ibm_u.immediate.ibim_payload, rlen,
+ to);
+ if (rc != rlen) {
+ rc = -EFAULT;
+ break;
+ }
+
+ rc = 0;
lnet_finalize(ni, lntmsg, 0);
break;