This is a note to let you know that I've just added the patch titled

scsi: sg: close race condition in sg_remove_sfp_usercontext()

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: scsi-sg-close-race-condition-in-sg_remove_sfp_usercontext.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Sun Mar 18 16:55:33 CET 2018

From: Hannes Reinecke hare@suse.de Date: Fri, 7 Apr 2017 09:34:17 +0200 Subject: scsi: sg: close race condition in sg_remove_sfp_usercontext()

From: Hannes Reinecke hare@suse.de

[ Upstream commit 97d27b0dd015e980ade63fda111fd1353276e28b ]

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 Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/sg.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)

--- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -524,6 +524,7 @@ sg_read(struct file *filp, char __user * } 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 *bu } 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 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)) { @@ -812,6 +815,7 @@ sg_common_write(Sg_fd * sfp, Sg_request }

sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); return -ENODEV; }

@@ -1302,6 +1306,7 @@ sg_rq_end_io_usercontext(struct work_str struct sg_fd *sfp = srp->parentfp;

sg_finish_rem_req(srp); + sg_remove_request(sfp, srp); kref_put(&sfp->f_ref, sg_remove_sfp); }

@@ -1846,8 +1851,6 @@ sg_finish_rem_req(Sg_request *srp) else sg_remove_scat(sfp, req_schp);

- sg_remove_request(sfp, srp); - return ret; }

@@ -2194,12 +2197,17 @@ sg_remove_sfp_usercontext(struct work_st 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,

Patches currently in stable-queue which might be from hare@suse.de are

queue-4.9/scsi-devinfo-apply-to-hp-xp-the-same-flags-as-hitachi-vsp.patch queue-4.9/scsi-sg-close-race-condition-in-sg_remove_sfp_usercontext.patch queue-4.9/scsi-dh-add-new-rdac-devices.patch