spi_transport_init() will call transport_class_register() twice. If the
2nd transport_class_register() failed, it won't unregister
spi_transport_class, which will causes the failed module cannot insert
anymore. Besides, spi_device_class is also not unregistered, which will
causes the page fault when another module calls
attribute_container_register().
Unregister spi_transport_class and spi_transport_class in fail path to
prevent page fault, and the problem that cannot insert anymore.
The bug is found when sym53c8xx failed in 2nd transport_class_register()
and then insert myrb:
BUG: unable to handle page fault for address: fffffbfff4001e4e
PGD 123ff2067 P4D 123ff2067 PUD 123f0e067 PMD 10d0a7067 PTE 0
Oops: 0000 [#1] SMP KASAN PTI
CPU: 3 PID: 20290 Comm: modprobe Tainted: G W
6.1.0-rc1-00180-g5d7833433b64 #253
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:attribute_container_register+0xcf/0x130
Call Trace:
<TASK>
? 0xffffffffa0038000
raid_class_attach+0x10d/0x218 [raid_class]
myrb_init_module+0x1c/0x1000 [myrb]
do_one_initcall+0xdb/0x480
? trace_event_raw_event_initcall_level+0x1c0/0x1c0
? rcu_read_lock_sched_held+0xa5/0xd0
? rcu_read_lock_bh_held+0xc0/0xc0
? __kmem_cache_alloc_node+0x3a8/0x7b0
? kasan_unpoison+0x23/0x50
? 0xffffffffa0038000
do_init_module+0x1cf/0x680
load_module+0x6a50/0x70a0
...
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Shang XiaoJing <shangxiaojing@xxxxxxxxxx>
---
drivers/scsi/scsi_transport_spi.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c
index f569cf0095c2..a0dbc5ce29c9 100644
--- a/drivers/scsi/scsi_transport_spi.c
+++ b/drivers/scsi/scsi_transport_spi.c
@@ -1622,7 +1622,20 @@ static __init int spi_transport_init(void)
if (error)
return error;
error = anon_transport_class_register(&spi_device_class);
- return transport_class_register(&spi_host_class);
+ if (error)
+ goto unregister_transport;
+
+ error = transport_class_register(&spi_host_class);
+ if (error)
+ goto unregister_device;
+
+ return 0;
+
+unregister_device:
+ anon_transport_class_unregister(&spi_device_class);
+unregister_transport:
+ transport_class_unregister(&spi_transport_class);
+ return error;
}
static void __exit spi_transport_exit(void)
--
2.17.1
