From 4f8dee2dec9c6d590c8a7844b2824935542ca122 Mon Sep 17 00:00:00 2001 From: Harsh Prateek Bora Date: Thu, 14 Apr 2011 14:54:40 +0530 Subject: v9fs_walk: As per 9p2000 RFC, MAXWELEM >= nwnames >= 0. The nwnames field in TWALK message is assumed to be >=0 and <= MAXWELEM which is defined as macro P9_MAXWELEM (16) in virtio-9p.h as per 9p2000 RFC. Appropriate changes are required in V9fsWalkState and v9fs_walk. Signed-off-by: Harsh Prateek Bora Reviewed-by: Stefan Hajnoczi Signed-off-by: Venkateswararao Jujjuri --- hw/9pfs/virtio-9p.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'hw/9pfs/virtio-9p.c') diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c index ca394570ca..b5fc52b3eb 100644 --- a/hw/9pfs/virtio-9p.c +++ b/hw/9pfs/virtio-9p.c @@ -1482,7 +1482,7 @@ static void v9fs_walk_complete(V9fsState *s, V9fsWalkState *vs, int err) { complete_pdu(s, vs->pdu, err); - if (vs->nwnames) { + if (vs->nwnames && vs->nwnames <= P9_MAXWELEM) { for (vs->name_idx = 0; vs->name_idx < vs->nwnames; vs->name_idx++) { v9fs_string_free(&vs->wnames[vs->name_idx]); } @@ -1578,7 +1578,7 @@ static void v9fs_walk(V9fsState *s, V9fsPDU *pdu) vs->offset += pdu_unmarshal(vs->pdu, vs->offset, "ddw", &fid, &newfid, &vs->nwnames); - if (vs->nwnames) { + if (vs->nwnames && vs->nwnames <= P9_MAXWELEM) { vs->wnames = qemu_mallocz(sizeof(vs->wnames[0]) * vs->nwnames); vs->qids = qemu_mallocz(sizeof(vs->qids[0]) * vs->nwnames); @@ -1587,6 +1587,9 @@ static void v9fs_walk(V9fsState *s, V9fsPDU *pdu) vs->offset += pdu_unmarshal(vs->pdu, vs->offset, "s", &vs->wnames[i]); } + } else if (vs->nwnames > P9_MAXWELEM) { + err = -EINVAL; + goto out; } vs->fidp = lookup_fid(s, fid); -- cgit v1.2.3