diff options
| -rw-r--r-- | hw/9pfs/9p.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index c63f549f39..9e046f7acb 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -2434,6 +2434,7 @@ static void coroutine_fn v9fs_readdir(void *opaque) int32_t count; uint32_t max_count; V9fsPDU *pdu = opaque; + V9fsState *s = pdu->s; retval = pdu_unmarshal(pdu, offset, "dqd", &fid, &initial_offset, &max_count); @@ -2442,6 +2443,14 @@ static void coroutine_fn v9fs_readdir(void *opaque) } trace_v9fs_readdir(pdu->tag, pdu->id, fid, initial_offset, max_count); + /* Enough space for a R_readdir header: size[4] Rreaddir tag[2] count[4] */ + if (max_count > s->msize - 11) { + max_count = s->msize - 11; + warn_report_once( + "9p: bad client: T_readdir with count > msize - 11" + ); + } + fidp = get_fid(pdu, fid); if (fidp == NULL) { retval = -EINVAL; |