The patch at the end is against 2.6.11.8. The kernel currently allows any user permitted to access the tape device file to send the tape drive commands that may either make the tape drivers internal state inconsistent or to change the drive parameters so that other users find the drive to be unusable. This patch changes ioctl handling so that SG_IO, SCSI_IOCTL_COMMAND, etc. require CAP_SYS_RAWIO. This solves the consistency problems for SCSI tapes. The st driver provides user-accessible commands to change the drive parameters that users may need to access. The SCSI command permissions were discussed on the linux lists and solutions enabling different rules for different devices were suggested. However, none of these has been implemented in the current kernel. It may very well be that the tape drives are the only devices that users are sometimes given permissions to access and that have security problems with the current command filtering. This patch solves the problem for tapes and no more elaborate patches are needed. If those are merged to the kernel, this patch can be reversed. Signed-off-by: Kai Makisara <kai.makisara@xxxxxxxxxxx> --- linux-2.6.11.8/drivers/scsi/st.c 2005-03-03 21:10:36.000000000 +0200 +++ linux-2.6.11.8-k1/drivers/scsi/st.c 2005-04-30 09:57:21.000000000 +0300 @@ -3414,7 +3414,10 @@ static int st_ioctl(struct inode *inode, case SCSI_IOCTL_GET_BUS_NUMBER: break; default: - i = scsi_cmd_ioctl(file, STp->disk, cmd_in, p); + if (!capable(CAP_SYS_RAWIO)) + i = -EPERM; + else + i = scsi_cmd_ioctl(file, STp->disk, cmd_in, p); if (i != -ENOTTY) return i; break; - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
