The server has crashed in ":sg:sg_add+0x349" while scanning for the new SAN devices

Issue

The server has crashed while scanning with rescan-scsi-bus.sh for the newly attached SAN devices with the following call trace in the kernel log:

sg_add: class_device_create failed
Unable to handle kernel NULL pointer dereference at 00000000000000af RIP: 
 [<ffffffff882eac53>] :sg:sg_add+0x349/0x453
PGD 268105067 PUD 1d6f73067 PMD 0 
Oops: 0002 [1] SMP 
last sysfs file: /devices/pci0000:00/0000:00:07.0/0000:06:00.1/host2/rport-2:0-2/target2:0:2/2:0:2:6/rev
CPU 12 
Modules linked in: st mptctl mptbase autofs4 bonding ipv6 ...skip...
Pid: 26152, comm: rescan-scsi-bus Not tainted 2.6.18-308.el5 #1
RIP: 0010:[<ffffffff882eac53>]  [<ffffffff882eac53>] :sg:sg_add+0x349/0x453
RSP: 0018:ffff8100b4095b98  EFLAGS: 00010286
RAX: 0000000000000026 RBX: ffffffffffffffef RCX: ffffffff80323028
RDX: ffffffff80323028 RSI: ffffffffffffffff RDI: ffff8102b75209d8
RBP: 0000000000000200 R08: ffffffff80323028 R09: 0000000000000001
R10: 0000000000000000 R11: 000000000000027f R12: 0000000000000040
R13: ffff81027c5033c0 R14: ffff8102cccd1800 R15: ffff8102b7520800
FS:  00002b6ff7bebf50(0000) GS:ffff81030bf20740(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000000000000af CR3: 000000027e7e3000 CR4: 00000000000006a0
Process rescan-scsi-bus (pid: 26152, threadinfo ffff8100b4094000, task ffff81017e9937e0)
Stack:  ffff8102b7520b50 ffff810092064dc0 0000000039fccb70 ffff81030a1e1000
 ffff810044da38e8 ffffffff882f07c0 ffff8102b7520b50 ffffffff8809ca90
 0000000000000000 ffff8102b7520b60 ffffffff8809c9a0 ffffffff801cf774
Call Trace:
 [<ffffffff801cf774>] class_device_add+0x323/0x422
 [<ffffffff8807e664>] :scsi_mod:scsi_sysfs_add_sdev+0x67/0x21b
 [<ffffffff8807c9ff>] :scsi_mod:scsi_probe_and_add_lun+0x8b1/0x9c9
 [<ffffffff8807b037>] :scsi_mod:scsi_execute_req+0x79/0xcf
 [<ffffffff8807d3ff>] :scsi_mod:__scsi_scan_target+0x410/0x5c7
 [<ffffffff8004c929>] sscanf+0x49/0x51
 [<ffffffff8807d874>] :scsi_mod:scsi_scan_target+0x73/0x8a
 [<ffffffff880d7558>] :scsi_transport_fc:fc_user_scan+0xe3/0x135
 [<ffffffff8807e1c4>] :scsi_mod:store_scan+0x9b/0xc5
 [<ffffffff80112648>] sysfs_write_file+0xb9/0xe8
 [<ffffffff80016b5d>] vfs_write+0xce/0x174
 [<ffffffff80017426>] sys_write+0x45/0x6e
 [<ffffffff8005d28d>] tracesys+0xd5/0xe0