| Message ID | 20210712134430.19372-1-yuehaibing@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | nl802154: Fix type check in nl802154_new_interface() | expand |
Hi, On Mon, 12 Jul 2021 at 09:49, YueHaibing <yuehaibing@huawei.com> wrote: > > We got this UBSAN warning: > > UBSAN: shift-out-of-bounds in net/ieee802154/nl802154.c:920:44 > shift exponent -1 is negative > CPU: 3 PID: 8258 Comm: repro Not tainted 5.13.0+ #222 > Call Trace: > dump_stack_lvl+0x8d/0xcf > ubsan_epilogue+0xa/0x4e > __ubsan_handle_shift_out_of_bounds+0x161/0x182 > nl802154_new_interface+0x3bf/0x3d0 > genl_family_rcv_msg_doit.isra.15+0x12d/0x170 > genl_rcv_msg+0x11a/0x240 > netlink_rcv_skb+0x69/0x160 > genl_rcv+0x24/0x40 > > NL802154_IFTYPE_UNSPEC is -1, so enum nl802154_iftype type now > is a signed integer, which is assigned by nla_get_u32 in > nl802154_new_interface(), this may cause type is negative and trigger > this warning. I think this is not the right fix, the fix is to change the UAPI that NL802154_IFTYPE_UNSPEC fits into the netlink range of U32. I will prepare a fix for that, it should still be backwards compatible. - Alex
diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c index 0cf2374..aab7ed4 100644 --- a/net/ieee802154/nl802154.c +++ b/net/ieee802154/nl802154.c @@ -915,7 +915,9 @@ static int nl802154_new_interface(struct sk_buff *skb, struct genl_info *info) if (info->attrs[NL802154_ATTR_IFTYPE]) { type = nla_get_u32(info->attrs[NL802154_ATTR_IFTYPE]); - if (type > NL802154_IFTYPE_MAX || + if (type < NL802154_IFTYPE_UNSPEC || type > NL802154_IFTYPE_MAX) + return -EINVAL; + if (type != NL802154_IFTYPE_UNSPEC && !(rdev->wpan_phy.supported.iftypes & BIT(type))) return -EINVAL; }
We got this UBSAN warning: UBSAN: shift-out-of-bounds in net/ieee802154/nl802154.c:920:44 shift exponent -1 is negative CPU: 3 PID: 8258 Comm: repro Not tainted 5.13.0+ #222 Call Trace: dump_stack_lvl+0x8d/0xcf ubsan_epilogue+0xa/0x4e __ubsan_handle_shift_out_of_bounds+0x161/0x182 nl802154_new_interface+0x3bf/0x3d0 genl_family_rcv_msg_doit.isra.15+0x12d/0x170 genl_rcv_msg+0x11a/0x240 netlink_rcv_skb+0x69/0x160 genl_rcv+0x24/0x40 NL802154_IFTYPE_UNSPEC is -1, so enum nl802154_iftype type now is a signed integer, which is assigned by nla_get_u32 in nl802154_new_interface(), this may cause type is negative and trigger this warning. Fixes: 65318680c97c ("ieee802154: add iftypes capability") Signed-off-by: YueHaibing <yuehaibing@huawei.com> --- net/ieee802154/nl802154.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)