| Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
net: fix crash when config small gso_max_size/gso_ipv4_max_size
Config a small gso_max_size/gso_ipv4_max_size will lead to an underflow
in sk_dst_gso_max_size(), which may trigger a BUG_ON crash,
because sk->sk_gso_max_size would be much bigger than device limits.
Call Trace:
tcp_write_xmit
tso_segs = tcp_init_tso_segs(skb, mss_now);
tcp_set_skb_tso_segs
tcp_skb_pcount_set
// skb->len = 524288, mss_now = 8
// u16 tso_segs = 524288/8 = 65535 -> 0
tso_segs = DIV_ROUND_UP(skb->len, mss_now)
BUG_ON(!tso_segs)
Add check for the minimum value of gso_max_size and gso_ipv4_max_size. |
