Author: brooks Date: Thu Oct 15 17:05:21 2020 New Revision: 366731 URL: https://svnweb.freebsd.org/changeset/base/366731
Log: physio: Don't store user addresses in bio_data Only assign the address from the iovec to bio_data if it is a kernel address. This was the single place where bio_data stored (however briefly) a userspace pointer. Reviewed by: imp, markj Obtained from: CheriBSD MFC after: 1 week Sponsored by: DARPA Differential Revision: https://reviews.freebsd.org/D26783 Modified: head/sys/kern/kern_physio.c Modified: head/sys/kern/kern_physio.c ============================================================================== --- head/sys/kern/kern_physio.c Thu Oct 15 15:36:08 2020 (r366730) +++ head/sys/kern/kern_physio.c Thu Oct 15 17:05:21 2020 (r366731) @@ -45,7 +45,7 @@ physio(struct cdev *dev, struct uio *uio, int ioflag) struct buf *pbuf; struct bio *bp; struct vm_page **pages; - caddr_t sa; + char *base, *sa; u_int iolen, poff; int error, i, npages, maxpages; vm_prot_t prot; @@ -140,7 +140,7 @@ physio(struct cdev *dev, struct uio *uio, int ioflag) curthread->td_ru.ru_oublock++; } bp->bio_offset = uio->uio_offset; - bp->bio_data = uio->uio_iov[i].iov_base; + base = uio->uio_iov[i].iov_base; bp->bio_length = uio->uio_iov[i].iov_len; if (bp->bio_length > dev->si_iosize_max) bp->bio_length = dev->si_iosize_max; @@ -153,13 +153,13 @@ physio(struct cdev *dev, struct uio *uio, int ioflag) * larger than MAXPHYS - PAGE_SIZE must be * page aligned or it will be fragmented. */ - poff = (vm_offset_t)bp->bio_data & PAGE_MASK; + poff = (vm_offset_t)base & PAGE_MASK; if (pbuf && bp->bio_length + poff > pbuf->b_kvasize) { if (dev->si_flags & SI_NOSPLIT) { uprintf("%s: request ptr %p is not " "on a page boundary; cannot split " "request\n", devtoname(dev), - bp->bio_data); + base); error = EFBIG; goto doerror; } @@ -174,7 +174,7 @@ physio(struct cdev *dev, struct uio *uio, int ioflag) if (pages) { if ((npages = vm_fault_quick_hold_pages( &curproc->p_vmspace->vm_map, - (vm_offset_t)bp->bio_data, bp->bio_length, + (vm_offset_t)base, bp->bio_length, prot, pages, maxpages)) < 0) { error = EFAULT; goto doerror; @@ -190,7 +190,8 @@ physio(struct cdev *dev, struct uio *uio, int ioflag) bp->bio_data = unmapped_buf; bp->bio_flags |= BIO_UNMAPPED; } - } + } else + bp->bio_data = base; csw->d_strategy(bp); if (uio->uio_rw == UIO_READ) _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
