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 4.14 23/23] 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
@@ -1443,7 +1443,7 @@ 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;
@@ -1478,7 +1478,7 @@ 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 19:43    [W:0.119 / U:0.292 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site