linux-stable/block/bsg-lib.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* BSG helper library
*
* Copyright (C) 2008 James Smart, Emulex Corporation
* Copyright (C) 2011 Red Hat, Inc. All rights reserved.
* Copyright (C) 2011 Mike Christie
*/
#include <linux/slab.h>
#include <linux/blk-mq.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <linux/bsg-lib.h>
#include <linux/export.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/sg.h>
#define uptr64(val) ((void __user *)(uintptr_t)(val))
struct bsg_set {
struct blk_mq_tag_set tag_set;
bsg_job_fn *job_fn;
bsg_timeout_fn *timeout_fn;
};
static int bsg_transport_check_proto(struct sg_io_v4 *hdr)
{
if (hdr->protocol != BSG_PROTOCOL_SCSI ||
hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_TRANSPORT)
return -EINVAL;
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
return 0;
}
static int bsg_transport_fill_hdr(struct request *rq, struct sg_io_v4 *hdr,
fmode_t mode)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
int ret;
job->request_len = hdr->request_len;
job->request = memdup_user(uptr64(hdr->request), hdr->request_len);
if (IS_ERR(job->request))
return PTR_ERR(job->request);
if (hdr->dout_xfer_len && hdr->din_xfer_len) {
job->bidi_rq = blk_get_request(rq->q, REQ_OP_SCSI_IN, 0);
if (IS_ERR(job->bidi_rq)) {
ret = PTR_ERR(job->bidi_rq);
goto out;
}
ret = blk_rq_map_user(rq->q, job->bidi_rq, NULL,
uptr64(hdr->din_xferp), hdr->din_xfer_len,
GFP_KERNEL);
if (ret)
goto out_free_bidi_rq;
job->bidi_bio = job->bidi_rq->bio;
} else {
job->bidi_rq = NULL;
job->bidi_bio = NULL;
}
return 0;
out_free_bidi_rq:
if (job->bidi_rq)
blk_put_request(job->bidi_rq);
out:
kfree(job->request);
return ret;
}
static int bsg_transport_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
int ret = 0;
/*
* The assignments below don't make much sense, but are kept for
* bug by bug backwards compatibility:
*/
hdr->device_status = job->result & 0xff;
hdr->transport_status = host_byte(job->result);
hdr->driver_status = driver_byte(job->result);
hdr->info = 0;
if (hdr->device_status || hdr->transport_status || hdr->driver_status)
hdr->info |= SG_INFO_CHECK;
hdr->response_len = 0;
if (job->result < 0) {
/* we're only returning the result field in the reply */
job->reply_len = sizeof(u32);
ret = job->result;
}
if (job->reply_len && hdr->response) {
int len = min(hdr->max_response_len, job->reply_len);
if (copy_to_user(uptr64(hdr->response), job->reply, len))
ret = -EFAULT;
else
hdr->response_len = len;
}
/* we assume all request payload was transferred, residual == 0 */
hdr->dout_resid = 0;
if (job->bidi_rq) {
unsigned int rsp_len = job->reply_payload.payload_len;
if (WARN_ON(job->reply_payload_rcv_len > rsp_len))
hdr->din_resid = 0;
else
hdr->din_resid = rsp_len - job->reply_payload_rcv_len;
} else {
hdr->din_resid = 0;
}
return ret;
}
static void bsg_transport_free_rq(struct request *rq)
{
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
if (job->bidi_rq) {
blk_rq_unmap_user(job->bidi_bio);
blk_put_request(job->bidi_rq);
}
kfree(job->request);
}
static const struct bsg_ops bsg_transport_ops = {
.check_proto = bsg_transport_check_proto,
.fill_hdr = bsg_transport_fill_hdr,
.complete_rq = bsg_transport_complete_rq,
.free_rq = bsg_transport_free_rq,
};
/**
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
* bsg_teardown_job - routine to teardown a bsg job
* @kref: kref inside bsg_job that is to be torn down
*/
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
static void bsg_teardown_job(struct kref *kref)
{
struct bsg_job *job = container_of(kref, struct bsg_job, kref);
struct request *rq = blk_mq_rq_from_pdu(job);
put_device(job->dev); /* release reference for the request */
kfree(job->request_payload.sg_list);
kfree(job->reply_payload.sg_list);
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
blk_mq_end_request(rq, BLK_STS_OK);
}
void bsg_job_put(struct bsg_job *job)
{
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
kref_put(&job->kref, bsg_teardown_job);
}
EXPORT_SYMBOL_GPL(bsg_job_put);
int bsg_job_get(struct bsg_job *job)
{
return kref_get_unless_zero(&job->kref);
}
EXPORT_SYMBOL_GPL(bsg_job_get);
/**
* bsg_job_done - completion routine for bsg requests
* @job: bsg_job that is complete
* @result: job reply result
* @reply_payload_rcv_len: length of payload recvd
*
* The LLD should call this when the bsg job has completed.
*/
void bsg_job_done(struct bsg_job *job, int result,
unsigned int reply_payload_rcv_len)
{
job->result = result;
job->reply_payload_rcv_len = reply_payload_rcv_len;
blk_mq_complete_request(blk_mq_rq_from_pdu(job));
}
EXPORT_SYMBOL_GPL(bsg_job_done);
/**
* bsg_complete - softirq done routine for destroying the bsg requests
* @rq: BSG request that holds the job to be destroyed
*/
static void bsg_complete(struct request *rq)
{
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
struct bsg_job *job = blk_mq_rq_to_pdu(rq);
bsg_job_put(job);
}
static int bsg_map_buffer(struct bsg_buffer *buf, struct request *req)
{
size_t sz = (sizeof(struct scatterlist) * req->nr_phys_segments);
BUG_ON(!req->nr_phys_segments);
buf->sg_list = kzalloc(sz, GFP_KERNEL);
if (!buf->sg_list)
return -ENOMEM;
sg_init_table(buf->sg_list, req->nr_phys_segments);
buf->sg_cnt = blk_rq_map_sg(req->q, req, buf->sg_list);
buf->payload_len = blk_rq_bytes(req);
return 0;
}
/**
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
* bsg_prepare_job - create the bsg_job structure for the bsg request
* @dev: device that is being sent the bsg request
* @req: BSG request that needs a job structure
*/
static bool bsg_prepare_job(struct device *dev, struct request *req)
{
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
struct bsg_job *job = blk_mq_rq_to_pdu(req);
int ret;
job->timeout = req->timeout;
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
if (req->bio) {
ret = bsg_map_buffer(&job->request_payload, req);
if (ret)
goto failjob_rls_job;
}
if (job->bidi_rq) {
ret = bsg_map_buffer(&job->reply_payload, job->bidi_rq);
if (ret)
goto failjob_rls_rqst_payload;
}
job->dev = dev;
/* take a reference for the request */
get_device(job->dev);
kref_init(&job->kref);
return true;
failjob_rls_rqst_payload:
kfree(job->request_payload.sg_list);
failjob_rls_job:
job->result = -ENOMEM;
return false;
}
/**
* bsg_queue_rq - generic handler for bsg requests
* @hctx: hardware queue
* @bd: queue data
*
* On error the create_bsg_job function should return a -Exyz error value
* that will be set to ->result.
*
* Drivers/subsys should pass this to the queue init function.
*/
static blk_status_t bsg_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct request_queue *q = hctx->queue;
struct device *dev = q->queuedata;
struct request *req = bd->rq;
struct bsg_set *bset =
container_of(q->tag_set, struct bsg_set, tag_set);
int sts = BLK_STS_IOERR;
int ret;
blk_mq_start_request(req);
if (!get_device(dev))
return BLK_STS_IOERR;
if (!bsg_prepare_job(dev, req))
goto out;
ret = bset->job_fn(blk_mq_rq_to_pdu(req));
if (!ret)
sts = BLK_STS_OK;
out:
put_device(dev);
return sts;
}
/* called right after the request is allocated for the request_queue */
static int bsg_init_rq(struct blk_mq_tag_set *set, struct request *req,
unsigned int hctx_idx, unsigned int numa_node)
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
bsg-lib: fix use-after-free under memory-pressure When under memory-pressure it is possible that the mempool which backs the 'struct request_queue' will make use of up to BLKDEV_MIN_RQ count emergency buffers - in case it can't get a regular allocation. These buffers are preallocated and once they are also used, they are re-supplied with old finished requests from the same request_queue (see mempool_free()). The bug is, when re-supplying the emergency pool, the old requests are not again ran through the callback mempool_t->alloc(), and thus also not through the callback bsg_init_rq(). Thus we skip initialization, and while the sense-buffer still should be good, scsi_request->cmd might have become to be an invalid pointer in the meantime. When the request is initialized in bsg.c, and the user's CDB is larger than BLK_MAX_CDB, bsg will replace it with a custom allocated buffer, which is freed when the user's command is finished, thus it dangles afterwards. When next a command is sent by the user that has a smaller/similar CDB as BLK_MAX_CDB, bsg will assume that scsi_request->cmd is backed by scsi_request->__cmd, will not make a custom allocation, and write into undefined memory. Fix this by splitting bsg_init_rq() into two functions: - bsg_init_rq() is changed to only do the allocation of the sense-buffer, which is used to back the bsg job's reply buffer. This pointer should never change during the lifetime of a scsi_request, so it doesn't need re-initialization. - bsg_initialize_rq() is a new function that makes use of 'struct request_queue's initialize_rq_fn callback (which was introduced in v4.12). This is always called before the request is given out via blk_get_request(). This function does the remaining initialization that was previously done in bsg_init_rq(), and will also do it when the request is taken from the emergency-pool of the backing mempool. Fixes: 50b4d485528d ("bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer") Cc: <stable@vger.kernel.org> # 4.11+ Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 10:48:37 +00:00
job->reply = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
if (!job->reply)
bsg-lib: fix use-after-free under memory-pressure When under memory-pressure it is possible that the mempool which backs the 'struct request_queue' will make use of up to BLKDEV_MIN_RQ count emergency buffers - in case it can't get a regular allocation. These buffers are preallocated and once they are also used, they are re-supplied with old finished requests from the same request_queue (see mempool_free()). The bug is, when re-supplying the emergency pool, the old requests are not again ran through the callback mempool_t->alloc(), and thus also not through the callback bsg_init_rq(). Thus we skip initialization, and while the sense-buffer still should be good, scsi_request->cmd might have become to be an invalid pointer in the meantime. When the request is initialized in bsg.c, and the user's CDB is larger than BLK_MAX_CDB, bsg will replace it with a custom allocated buffer, which is freed when the user's command is finished, thus it dangles afterwards. When next a command is sent by the user that has a smaller/similar CDB as BLK_MAX_CDB, bsg will assume that scsi_request->cmd is backed by scsi_request->__cmd, will not make a custom allocation, and write into undefined memory. Fix this by splitting bsg_init_rq() into two functions: - bsg_init_rq() is changed to only do the allocation of the sense-buffer, which is used to back the bsg job's reply buffer. This pointer should never change during the lifetime of a scsi_request, so it doesn't need re-initialization. - bsg_initialize_rq() is a new function that makes use of 'struct request_queue's initialize_rq_fn callback (which was introduced in v4.12). This is always called before the request is given out via blk_get_request(). This function does the remaining initialization that was previously done in bsg_init_rq(), and will also do it when the request is taken from the emergency-pool of the backing mempool. Fixes: 50b4d485528d ("bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer") Cc: <stable@vger.kernel.org> # 4.11+ Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 10:48:37 +00:00
return -ENOMEM;
return 0;
}
/* called right before the request is given to the request_queue user */
bsg-lib: fix use-after-free under memory-pressure When under memory-pressure it is possible that the mempool which backs the 'struct request_queue' will make use of up to BLKDEV_MIN_RQ count emergency buffers - in case it can't get a regular allocation. These buffers are preallocated and once they are also used, they are re-supplied with old finished requests from the same request_queue (see mempool_free()). The bug is, when re-supplying the emergency pool, the old requests are not again ran through the callback mempool_t->alloc(), and thus also not through the callback bsg_init_rq(). Thus we skip initialization, and while the sense-buffer still should be good, scsi_request->cmd might have become to be an invalid pointer in the meantime. When the request is initialized in bsg.c, and the user's CDB is larger than BLK_MAX_CDB, bsg will replace it with a custom allocated buffer, which is freed when the user's command is finished, thus it dangles afterwards. When next a command is sent by the user that has a smaller/similar CDB as BLK_MAX_CDB, bsg will assume that scsi_request->cmd is backed by scsi_request->__cmd, will not make a custom allocation, and write into undefined memory. Fix this by splitting bsg_init_rq() into two functions: - bsg_init_rq() is changed to only do the allocation of the sense-buffer, which is used to back the bsg job's reply buffer. This pointer should never change during the lifetime of a scsi_request, so it doesn't need re-initialization. - bsg_initialize_rq() is a new function that makes use of 'struct request_queue's initialize_rq_fn callback (which was introduced in v4.12). This is always called before the request is given out via blk_get_request(). This function does the remaining initialization that was previously done in bsg_init_rq(), and will also do it when the request is taken from the emergency-pool of the backing mempool. Fixes: 50b4d485528d ("bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer") Cc: <stable@vger.kernel.org> # 4.11+ Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 10:48:37 +00:00
static void bsg_initialize_rq(struct request *req)
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
void *reply = job->reply;
bsg-lib: fix use-after-free under memory-pressure When under memory-pressure it is possible that the mempool which backs the 'struct request_queue' will make use of up to BLKDEV_MIN_RQ count emergency buffers - in case it can't get a regular allocation. These buffers are preallocated and once they are also used, they are re-supplied with old finished requests from the same request_queue (see mempool_free()). The bug is, when re-supplying the emergency pool, the old requests are not again ran through the callback mempool_t->alloc(), and thus also not through the callback bsg_init_rq(). Thus we skip initialization, and while the sense-buffer still should be good, scsi_request->cmd might have become to be an invalid pointer in the meantime. When the request is initialized in bsg.c, and the user's CDB is larger than BLK_MAX_CDB, bsg will replace it with a custom allocated buffer, which is freed when the user's command is finished, thus it dangles afterwards. When next a command is sent by the user that has a smaller/similar CDB as BLK_MAX_CDB, bsg will assume that scsi_request->cmd is backed by scsi_request->__cmd, will not make a custom allocation, and write into undefined memory. Fix this by splitting bsg_init_rq() into two functions: - bsg_init_rq() is changed to only do the allocation of the sense-buffer, which is used to back the bsg job's reply buffer. This pointer should never change during the lifetime of a scsi_request, so it doesn't need re-initialization. - bsg_initialize_rq() is a new function that makes use of 'struct request_queue's initialize_rq_fn callback (which was introduced in v4.12). This is always called before the request is given out via blk_get_request(). This function does the remaining initialization that was previously done in bsg_init_rq(), and will also do it when the request is taken from the emergency-pool of the backing mempool. Fixes: 50b4d485528d ("bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer") Cc: <stable@vger.kernel.org> # 4.11+ Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 10:48:37 +00:00
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
memset(job, 0, sizeof(*job));
job->reply = reply;
job->reply_len = SCSI_SENSE_BUFFERSIZE;
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
job->dd_data = job + 1;
}
static void bsg_exit_rq(struct blk_mq_tag_set *set, struct request *req,
unsigned int hctx_idx)
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
{
struct bsg_job *job = blk_mq_rq_to_pdu(req);
kfree(job->reply);
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer Since we split the scsi_request out of struct request bsg fails to provide a reply-buffer for the drivers. This was done via the pointer for sense-data, that is not preallocated anymore. Failing to allocate/assign it results in illegal dereferences because LLDs use this pointer unquestioned. An example panic on s390x, using the zFCP driver, looks like this (I had debugging on, otherwise NULL-pointer dereferences wouldn't even panic on s390x): Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403 Fault in home space mode while using kernel ASCE. AS:0000000001590007 R3:0000000000000024 Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: <Long List> CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) task: 0000000065cb0100 task.stack: 0000000065cb4000 Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866 000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f 00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38 0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8 Krnl Code: 000003ff801e4146: e31020500004 lg %r1,80(%r2) 000003ff801e414c: 58402040 l %r4,64(%r2) #000003ff801e4150: e35020200004 lg %r5,32(%r2) >000003ff801e4156: 50405004 st %r4,4(%r5) 000003ff801e415a: e54c50080000 mvhi 8(%r5),0 000003ff801e4160: e33010280012 lt %r3,40(%r1) 000003ff801e4166: a718fffb lhi %r1,-5 000003ff801e416a: 1803 lr %r0,%r3 Call Trace: ([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp]) [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp] [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp] [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10 [<00000000001684c2>] tasklet_action+0x15a/0x1d8 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848 [<00000000001675a4>] irq_exit+0x74/0xf8 [<000000000010dd6a>] do_IRQ+0xba/0xf0 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4 [<00000000001033b6>] enabled_wait+0xb6/0x188 ([<000000000010339e>] enabled_wait+0x9e/0x188) [<000000000010396a>] arch_cpu_idle+0x32/0x50 [<0000000000bd0112>] default_idle_call+0x52/0x68 [<00000000001cd0fa>] do_idle+0x102/0x188 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48 [<0000000000118c64>] smp_start_secondary+0x11c/0x130 [<0000000000bd2016>] restart_int_handler+0x62/0x78 [<0000000000000000>] (null) INFO: lockdep is turned off. Last Breaking-Event-Address: [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp] Kernel panic - not syncing: Fatal exception in interrupt This patch moves bsg-lib to allocate and setup struct bsg_job ahead of time, including the allocation of a buffer for the reply-data. This means, struct bsg_job is not allocated separately anymore, but as part of struct request allocation - similar to struct scsi_cmd. Reflect this in the function names that used to handle creation/destruction of struct bsg_job. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Cc: <stable@vger.kernel.org> #4.11+ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 23:57:56 +00:00
}
void bsg_remove_queue(struct request_queue *q)
{
if (q) {
struct bsg_set *bset =
container_of(q->tag_set, struct bsg_set, tag_set);
bsg_unregister_queue(q);
blk_cleanup_queue(q);
blk_mq_free_tag_set(&bset->tag_set);
kfree(bset);
}
}
EXPORT_SYMBOL_GPL(bsg_remove_queue);
static enum blk_eh_timer_return bsg_timeout(struct request *rq, bool reserved)
{
struct bsg_set *bset =
container_of(rq->q->tag_set, struct bsg_set, tag_set);
if (!bset->timeout_fn)
return BLK_EH_DONE;
return bset->timeout_fn(rq);
}
static const struct blk_mq_ops bsg_mq_ops = {
.queue_rq = bsg_queue_rq,
.init_request = bsg_init_rq,
.exit_request = bsg_exit_rq,
.initialize_rq_fn = bsg_initialize_rq,
.complete = bsg_complete,
.timeout = bsg_timeout,
};
/**
* bsg_setup_queue - Create and add the bsg hooks so we can receive requests
* @dev: device to attach bsg device to
* @name: device to give bsg device
* @job_fn: bsg job handler
* @timeout: timeout handler function pointer
* @dd_job_size: size of LLD data needed for each job
*/
struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size)
{
struct bsg_set *bset;
struct blk_mq_tag_set *set;
struct request_queue *q;
int ret = -ENOMEM;
bset = kzalloc(sizeof(*bset), GFP_KERNEL);
if (!bset)
return ERR_PTR(-ENOMEM);
bset->job_fn = job_fn;
bset->timeout_fn = timeout;
set = &bset->tag_set;
set->ops = &bsg_mq_ops,
set->nr_hw_queues = 1;
set->queue_depth = 128;
set->numa_node = NUMA_NO_NODE;
set->cmd_size = sizeof(struct bsg_job) + dd_job_size;
set->flags = BLK_MQ_F_NO_SCHED | BLK_MQ_F_BLOCKING;
if (blk_mq_alloc_tag_set(set))
goto out_tag_set;
q = blk_mq_init_queue(set);
if (IS_ERR(q)) {
ret = PTR_ERR(q);
goto out_queue;
}
q->queuedata = dev;
blk_queue_rq_timeout(q, BLK_DEFAULT_SG_TIMEOUT);
ret = bsg_register_queue(q, dev, name, &bsg_transport_ops);
if (ret) {
printk(KERN_ERR "%s: bsg interface failed to "
"initialize - register queue\n", dev->kobj.name);
goto out_cleanup_queue;
}
return q;
out_cleanup_queue:
blk_cleanup_queue(q);
out_queue:
blk_mq_free_tag_set(set);
out_tag_set:
kfree(bset);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(bsg_setup_queue);