lkml.org 
[lkml]   [2022]   [Jun]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.9 12/12] bpf: Enlarge offset check value to INT_MAX in bpf_skb_{load,store}_bytes
    Date
    From: Liu Jian <liujian56@huawei.com>

    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>
    ---
    net/core/filter.c | 4 ++--
    1 file changed, 2 insertions(+), 2 deletions(-)

    --- a/net/core/filter.c
    +++ b/net/core/filter.c
    @@ -1388,7 +1388,7 @@ BPF_CALL_5(bpf_skb_store_bytes, struct s

    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;
    @@ -1423,7 +1423,7 @@ BPF_CALL_4(bpf_skb_load_bytes, const str
    {
    void *ptr;

    - if (unlikely(offset > 0xffff))
    + if (unlikely(offset > INT_MAX))
    goto err_clear;

    ptr = skb_header_pointer(skb, offset, len, to);

    \
     
     \ /
      Last update: 2022-06-03 19:42    [W:5.094 / U:0.024 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site