On 04/29/2012 01:59 AM, Xi Wang wrote: > On 32-bit systems, a large `pglen' would overflow `pglen*sizeof(u32)' > and bypass the check ceph_decode_need(p, end, pglen*sizeof(u32), bad). > It would also overflow the subsequent kmalloc() size, leading to > out-of-bounds write. > > Signed-off-by: Xi Wang <[email protected]>
This looks good. I'll wait to hear back on my comments on your earlier patches before committing these. Reviewed-by: Alex Elder <[email protected]> > --- > net/ceph/osdmap.c | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) > > diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c > index 774eac6..b1ea6d1 100644 > --- a/net/ceph/osdmap.c > +++ b/net/ceph/osdmap.c > @@ -891,6 +891,10 @@ struct ceph_osdmap *osdmap_apply_incremental(void **p, > void *end, > > if (pglen) { > /* insert */ > + if (pglen > (UINT_MAX - sizeof(*pg)) / sizeof(u32)) { > + err = -EINVAL; > + goto bad; > + } > ceph_decode_need(p, end, pglen*sizeof(u32), bad); > pg = kmalloc(sizeof(*pg) + sizeof(u32)*pglen, GFP_NOFS); > if (!pg) { -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
