3.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Xi Wang <xi.w...@gmail.com> (cherry picked from commit a5506049500b30dbc5edb4d07a3577477c1f3643) 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 <xi.w...@gmail.com> Reviewed-by: Alex Elder <el...@inktank.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- net/ceph/osdmap.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/ceph/osdmap.c +++ b/net/ceph/osdmap.c @@ -900,6 +900,10 @@ struct ceph_osdmap *osdmap_apply_increme (void) __remove_pg_mapping(&map->pg_temp, pgid); /* insert */ + if (pglen > (UINT_MAX - sizeof(*pg)) / sizeof(u32)) { + err = -EINVAL; + goto bad; + } pg = kmalloc(sizeof(*pg) + sizeof(u32)*pglen, GFP_NOFS); if (!pg) { err = -ENOMEM; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/