[SCSI] Fix NULL dereferences in scsi_cmd_to_driver
Avoid crashing if the private_data pointer happens to be NULL. This has been seen sometimes when a host reset happens, notably when there are many LUNs: host3: Assigned Port ID 0c1601 scsi host3: libfc: Host reset succeeded on port (0c1601) BUG: unable to handle kernel NULL pointer dereference at 0000000000000350 IP: [<ffffffff81352bb8>] scsi_send_eh_cmnd+0x58/0x3a0 <snip> Process scsi_eh_3 (pid: 4144, threadinfo ffff88030920c000, task ffff880326b160c0) Stack: 000000010372e6ba 0000000000000282 000027100920dca0 ffffffffa0038ee0 0000000000000000 0000000000030003 ffff88030920dc80 ffff88030920dc80 00000002000e0000 0000000a00004000 ffff8803242f7760 ffff88031326ed80 Call Trace: [<ffffffff8105b590>] ? lock_timer_base+0x70/0x70 [<ffffffff81352fbe>] scsi_eh_tur+0x3e/0xc0 [<ffffffff81353a36>] scsi_eh_test_devices+0x76/0x170 [<ffffffff81354125>] scsi_eh_host_reset+0x85/0x160 [<ffffffff81354291>] scsi_eh_ready_devs+0x91/0x110 [<ffffffff813543fd>] scsi_unjam_host+0xed/0x1f0 [<ffffffff813546a8>] scsi_error_handler+0x1a8/0x200 [<ffffffff81354500>] ? scsi_unjam_host+0x1f0/0x1f0 [<ffffffff8106ec3e>] kthread+0x9e/0xb0 [<ffffffff81509264>] kernel_thread_helper+0x4/0x10 [<ffffffff8106eba0>] ? kthread_freezable_should_stop+0x70/0x70 [<ffffffff81509260>] ? gs_change+0x13/0x13 Code: 25 28 00 00 00 48 89 45 c8 31 c0 48 8b 87 80 00 00 00 48 8d b5 60 ff ff ff 89 d1 48 89 fb 41 89 d6 4c 89 fa 48 8b 80 b8 00 00 00 <48> 8b 80 50 03 00 00 48 8b 00 48 89 85 38 ff ff ff 48 8b 07 4c RIP [<ffffffff81352bb8>] scsi_send_eh_cmnd+0x58/0x3a0 RSP <ffff88030920dc50> CR2: 0000000000000350 Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Tested-by: Marcus Dennis <marcusx.e.dennis@intel.com> Cc: <stable@kernel.org> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
parent
bd0a521e88
commit
222a806af8
|
@ -134,10 +134,16 @@ struct scsi_cmnd {
|
|||
|
||||
static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd)
|
||||
{
|
||||
struct scsi_driver **sdp;
|
||||
|
||||
if (!cmd->request->rq_disk)
|
||||
return NULL;
|
||||
|
||||
return *(struct scsi_driver **)cmd->request->rq_disk->private_data;
|
||||
sdp = (struct scsi_driver **)cmd->request->rq_disk->private_data;
|
||||
if (!sdp)
|
||||
return NULL;
|
||||
|
||||
return *sdp;
|
||||
}
|
||||
|
||||
extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t);
|
||||
|
|
Loading…
Reference in New Issue