diff options
author | Bart Van Assche <bart.vanassche@sandisk.com> | 2017-06-02 14:21:52 -0700 |
---|---|---|
committer | Martin K. Petersen <martin.petersen@oracle.com> | 2017-06-12 20:55:58 -0400 |
commit | 8e6882545d8c06f99e9e117741cc87f3338b0bef (patch) | |
tree | 12a6bb40ee60e460788b3b45cddce7326dba6a4f /include/scsi | |
parent | 896f6966fc815abe71f85fb26f0193875df8a035 (diff) |
scsi: Avoid that scsi_exit_rq() triggers a use-after-free
Dereferencing shost from scsi_exit_rq() is not safe because the SCSI
host may already have been freed when scsi_exit_rq() is called.
Increasing the shost reference count in scsi_init_rq() and dropping that
reference in scsi_exit_rq() is nontrivial since scsi_host_dev_release()
may sleep and since scsi_exit_rq() may be called from interrupt
context. Since scsi_exit_rq() only needs a single bit from shost, copy
that bit into struct scsi_cmnd.
Reported-by: Scott Bauer <scott.bauer@intel.com>
Fixes: e9c787e65c0c ("scsi: allocate scsi_cmnd structures as part of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Scott Bauer <scott.bauer@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'include/scsi')
-rw-r--r-- | include/scsi/scsi_cmnd.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index b379f93a2c48..16351de31243 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -56,6 +56,7 @@ struct scsi_pointer { /* for scmd->flags */ #define SCMD_TAGGED (1 << 0) +#define SCMD_UNCHECKED_ISA_DMA (1 << 1) struct scsi_cmnd { struct scsi_request req; |