path: root/block/bsg.c
diff options
authorJames Smart <james.smart@emulex.com>2010-11-14 11:12:04 -0500
committerJames Bottomley <James.Bottomley@suse.de>2010-12-09 09:41:14 -0600
commitc7a841f3aca469187db76842676951a672fd27d1 (patch)
tree6819d796270f9b4c5eb4cae374a69ab1988d384a /block/bsg.c
parent057f02a38e67a944a2d0b89bb0111efb9dbe6e6e (diff)
[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>
Diffstat (limited to 'block/bsg.c')
1 files changed, 8 insertions, 0 deletions
diff --git a/block/bsg.c b/block/bsg.c
index f20d6a789d48..0c8b64a16484 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -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,