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| author | Joe Lawrence <joe.lawrence@stratus.com> | 2014-07-02 21:35:16 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2014-08-26 23:20:23 +0200 |
| commit | eb571eeade2598635f813b3284d02c13a380301e (patch) | |
| tree | 539842ad23a4eaae8c272278fd9fea389afa6b93 | |
| parent | Linux 3.17-rc2 (diff) | |
| download | linux-eb571eeade2598635f813b3284d02c13a380301e.tar.xz linux-eb571eeade2598635f813b3284d02c13a380301e.zip | |
block,scsi: verify return pointer from blk_get_request
The blk-core dead queue checks introduce an error scenario to
blk_get_request that returns NULL if the request queue has been
shutdown. This affects the behavior for __GFP_WAIT callers, who should
verify the return value before dereferencing.
Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd]
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | block/scsi_ioctl.c | 9 | ||||
| -rw-r--r-- | drivers/block/paride/pd.c | 2 | ||||
| -rw-r--r-- | drivers/block/pktcdvd.c | 2 | ||||
| -rw-r--r-- | drivers/scsi/scsi_error.c | 2 |
4 files changed, 14 insertions, 1 deletions
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index 51bf5155ee75..29d056782833 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -448,6 +448,10 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode, } rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT); + if (!rq) { + err = -ENODEV; + goto error_free_buffer; + } cmdlen = COMMAND_SIZE(opcode); @@ -520,8 +524,9 @@ out: } error: - kfree(buffer); blk_put_request(rq); +error_free_buffer: + kfree(buffer); return err; } EXPORT_SYMBOL_GPL(sg_scsi_ioctl); @@ -534,6 +539,8 @@ static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk, int err; rq = blk_get_request(q, WRITE, __GFP_WAIT); + if (!rq) + return -ENODEV; blk_rq_set_block_pc(rq); rq->timeout = BLK_DEFAULT_SG_TIMEOUT; rq->cmd[0] = cmd; diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c index fea7e76a00de..ca831f741d89 100644 --- a/drivers/block/paride/pd.c +++ b/drivers/block/paride/pd.c @@ -722,6 +722,8 @@ static int pd_special_command(struct pd_unit *disk, int err = 0; rq = blk_get_request(disk->gd->queue, READ, __GFP_WAIT); + if (!rq) + return -ENODEV; rq->cmd_type = REQ_TYPE_SPECIAL; rq->special = func; diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index 758ac442c5b5..7fa8c80e8982 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -704,6 +704,8 @@ static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command * rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ, __GFP_WAIT); + if (!rq) + return -ENODEV; blk_rq_set_block_pc(rq); if (cgc->buflen) { diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 5db8454474ee..4c433bf47a06 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -1960,6 +1960,8 @@ static void scsi_eh_lock_door(struct scsi_device *sdev) * request becomes available */ req = blk_get_request(sdev->request_queue, READ, GFP_KERNEL); + if (!req) + return; blk_rq_set_block_pc(req); |