From: Liu Jian <liujian56@huawei.com> stable inclusion from stable-4.19.246 commit 22771d3095deeca0d2aefd55999fa8a50caea3cd category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5FNPY CVE: NA -------------------------------- commit 45969b4152c1752089351cd6836a42a566d49bcf upstream. The data length of skb frags + frag_list may be greater than 0xffff, and skb_header_pointer can not handle negative offset. So, here INT_MAX is used to check the validity of offset. Add the same change to the related function skb_store_bytes. Fixes: 05c74e5e53f6 ("bpf: add bpf_skb_load_bytes helper") Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20220416105801.88708-2-liujian56@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com> Signed-off-by: Laibin Qiu <qiulaibin@huawei.com> --- net/core/filter.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 0730395918e0..7a3655e14764 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1666,7 +1666,7 @@ BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset, if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH))) return -EINVAL; - if (unlikely(offset > 0xffff)) + if (unlikely(offset > INT_MAX)) return -EFAULT; if (unlikely(bpf_try_make_writable(skb, offset + len))) return -EFAULT; @@ -1701,7 +1701,7 @@ BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset, { void *ptr; - if (unlikely(offset > 0xffff)) + if (unlikely(offset > INT_MAX)) goto err_clear; ptr = skb_header_pointer(skb, offset, len, to); -- 2.25.1