diff options
| author | Hannes Reinecke <hare@suse.de> | 2017-04-07 09:34:17 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2017-04-12 02:55:20 +0200 |
| commit | 97d27b0dd015e980ade63fda111fd1353276e28b (patch) | |
| tree | 73d20113d2a708816b6194c0519431db1e792700 /drivers/scsi/sg.c | |
| parent | scsi: sg: use standard lists for sg_requests (diff) | |
| download | linux-97d27b0dd015e980ade63fda111fd1353276e28b.tar.xz linux-97d27b0dd015e980ade63fda111fd1353276e28b.zip | |
scsi: sg: close race condition in sg_remove_sfp_usercontext()
sg_remove_sfp_usercontext() is clearing any sg requests, but needs to
take 'rq_list_lock' when modifying the list.
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/sg.c')
| -rw-r--r-- | drivers/scsi/sg.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 5c9f1b9f69e9..8147147df2f4 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -524,6 +524,7 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) } else count = (old_hdr->result == 0) ? 0 : -EIO; sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); retval = count; free_old_hdr: kfree(old_hdr); @@ -564,6 +565,7 @@ sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) } err_out: err2 = sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); return err ? : err2 ? : count; } @@ -800,6 +802,7 @@ sg_common_write(Sg_fd * sfp, Sg_request * srp, SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, "sg_common_write: start_req err=%d\n", k)); sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); return k; /* probably out of space --> ENOMEM */ } if (atomic_read(&sdp->detaching)) { @@ -810,6 +813,7 @@ sg_common_write(Sg_fd * sfp, Sg_request * srp, } sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); return -ENODEV; } @@ -1285,6 +1289,7 @@ sg_rq_end_io_usercontext(struct work_struct *work) struct sg_fd *sfp = srp->parentfp; sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); kref_put(&sfp->f_ref, sg_remove_sfp); } @@ -1831,8 +1836,6 @@ sg_finish_rem_req(Sg_request *srp) else sg_remove_scat(sfp, req_schp); - sg_remove_request(sfp, srp); - return ret; } @@ -2177,12 +2180,17 @@ sg_remove_sfp_usercontext(struct work_struct *work) struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); struct sg_device *sdp = sfp->parentdp; Sg_request *srp; + unsigned long iflags; /* Cleanup any responses which were never read(). */ + write_lock_irqsave(&sfp->rq_list_lock, iflags); while (!list_empty(&sfp->rq_list)) { srp = list_first_entry(&sfp->rq_list, Sg_request, entry); sg_finish_rem_req(srp); + list_del(&srp->entry); + srp->parentfp = NULL; } + write_unlock_irqrestore(&sfp->rq_list_lock, iflags); if (sfp->reserve.bufflen > 0) { SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, |