Commit c7a841f3 authored Nov 14, 2010 by James Smart Committed by James Bottomley Dec 09, 2010

[SCSI] bsg: correct fault if queue object removed while dev_t open



This patch corrects an issue in bsg that results in a general protection
fault if an LLD is removed while an application is using an open file
handle to a bsg device, and the application issues an ioctl. The fault
occurs because the class_dev is NULL, having been cleared in
bsg_unregister_queue() when the driver was removed.  With this
patch, a check is made for the class_dev, and the application
will receive ENXIO if the related object is gone.

Signed-off-by: Carl Lajeunesse <carl.lajeunesse@emulex.com>
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

parent 057f02a3

block/bsg.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -250,6 +250,14 @@ bsg_map_hdr(struct bsg_device bd, struct sg_io_v4 hdr, fmode_t has_write_perm,
		int ret, rw;
		unsigned int dxfer_len;
		void *dxferp = NULL;
		struct bsg_class_device *bcd = &q->bsg_dev;

		/* if the LLD has been removed then the bsg_unregister_queue will
		* eventually be called and the class_dev was freed, so we can no
		* longer use this request_queue. Return no such address.
		*/
		if (!bcd->class_dev)
		return ERR_PTR(-ENXIO);

		dprintk("map hdr %llx/%u %llx/%u\n", (unsigned long long) hdr->dout_xferp,
		hdr->dout_xfer_len, (unsigned long long) hdr->din_xferp,

Admin message