4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Bart Van Assche <bvanassche@xxxxxxx>
commit ed041919f0d23c109d52cde8da6ddc211c52d67e upstream.
This patch avoids that KASAN sporadically reports the following:
BUG: KASAN: use-after-free in rxe_run_task+0x1e/0x60 [rdma_rxe]
Read of size 1 at addr ffff88801c50d8f4 by task check/24830
CPU: 4 PID: 24830 Comm: check Not tainted 4.20.0-rc6-dbg+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
dump_stack+0x86/0xca
print_address_description+0x71/0x239
kasan_report.cold.5+0x242/0x301
__asan_load1+0x47/0x50
rxe_run_task+0x1e/0x60 [rdma_rxe]
rxe_post_send+0x4bd/0x8d0 [rdma_rxe]
srpt_zerolength_write+0xe1/0x160 [ib_srpt]
srpt_close_ch+0x8b/0xe0 [ib_srpt]
srpt_set_enabled+0xe7/0x150 [ib_srpt]
srpt_tpg_enable_store+0xc0/0x100 [ib_srpt]
configfs_write_file+0x157/0x1d0
__vfs_write+0xd7/0x3d0
vfs_write+0x102/0x290
ksys_write+0xab/0x130
__x64_sys_write+0x43/0x50
do_syscall_64+0x71/0x210
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Allocated by task 13856:
save_stack+0x43/0xd0
kasan_kmalloc+0xc7/0xe0
kasan_slab_alloc+0x11/0x20
kmem_cache_alloc+0x105/0x320
rxe_alloc+0xff/0x1f0 [rdma_rxe]
rxe_create_qp+0x9f/0x160 [rdma_rxe]
ib_create_qp+0xf5/0x690 [ib_core]
rdma_create_qp+0x6a/0x140 [rdma_cm]
srpt_cm_req_recv.cold.59+0x1588/0x237b [ib_srpt]
srpt_rdma_cm_req_recv.isra.35+0x1d5/0x220 [ib_srpt]
srpt_rdma_cm_handler+0x6f/0x100 [ib_srpt]
cma_listen_handler+0x59/0x60 [rdma_cm]
cma_ib_req_handler+0xd5b/0x2570 [rdma_cm]
cm_process_work+0x2e/0x110 [ib_cm]
cm_work_handler+0x2aae/0x502b [ib_cm]
process_one_work+0x481/0x9e0
worker_thread+0x67/0x5b0
kthread+0x1cf/0x1f0
ret_from_fork+0x24/0x30
Freed by task 3440:
save_stack+0x43/0xd0
__kasan_slab_free+0x139/0x190
kasan_slab_free+0xe/0x10
kmem_cache_free+0xbc/0x330
rxe_elem_release+0x66/0xe0 [rdma_rxe]
rxe_destroy_qp+0x3f/0x50 [rdma_rxe]
ib_destroy_qp+0x140/0x360 [ib_core]
srpt_release_channel_work+0xdc/0x310 [ib_srpt]
process_one_work+0x481/0x9e0
worker_thread+0x67/0x5b0
kthread+0x1cf/0x1f0
ret_from_fork+0x24/0x30
Cc: Sergey Gorenko <sergeygo@xxxxxxxxxxxx>
Cc: Max Gurtovoy <maxg@xxxxxxxxxxxx>
Cc: Laurence Oberman <loberman@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/ulp/srpt/ib_srpt.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -2010,6 +2010,14 @@ static void srpt_free_ch(struct kref *kr
kfree_rcu(ch, rcu);
}
+/*
+ * Shut down the SCSI target session, tell the connection manager to
+ * disconnect the associated RDMA channel, transition the QP to the error
+ * state and remove the channel from the channel list. This function is
+ * typically called from inside srpt_zerolength_write_done(). Concurrent
+ * srpt_zerolength_write() calls from inside srpt_close_ch() are possible
+ * as long as the channel is on sport->nexus_list.
+ */
static void srpt_release_channel_work(struct work_struct *w)
{
struct srpt_rdma_ch *ch;
@@ -2037,6 +2045,11 @@ static void srpt_release_channel_work(st
else
ib_destroy_cm_id(ch->ib_cm.cm_id);
+ sport = ch->sport;
+ mutex_lock(&sport->mutex);
+ list_del_rcu(&ch->list);
+ mutex_unlock(&sport->mutex);
+
srpt_destroy_ch_ib(ch);
srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
@@ -2047,11 +2060,6 @@ static void srpt_release_channel_work(st
sdev, ch->rq_size,
srp_max_req_size, DMA_FROM_DEVICE);
- sport = ch->sport;
- mutex_lock(&sport->mutex);
- list_del_rcu(&ch->list);
- mutex_unlock(&sport->mutex);
-
wake_up(&sport->ch_releaseQ);
kref_put(&ch->kref, srpt_free_ch);
