diff options
| author | Kees Cook <keescook@chromium.org> | 2021-11-20 16:31:49 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-11-22 15:13:54 +0000 |
| commit | 03f61041c17914355dde7261be9ccdc821ddd454 (patch) | |
| tree | bd95497df8f59b9729f69d97ac8092e48e0523c9 /include | |
| parent | fba84957e2e2e201cf4e352efe0c7cac0fbb5d5d (diff) | |
skbuff: Switch structure bounds to struct_group()
In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally writing across neighboring fields.
Replace the existing empty member position markers "headers_start" and
"headers_end" with a struct_group(). This will allow memcpy() and sizeof()
to more easily reason about sizes, and improve readability.
"pahole" shows no size nor member offset changes to struct sk_buff.
"objdump -d" shows no object code changes (outside of WARNs affected by
source line number changes).
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com> # drivers/net/wireguard/*
Link: https://lore.kernel.org/lkml/20210728035006.GD35706@embeddedor
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/skbuff.h | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index c7889afe0d0d..eba256af64a5 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -811,12 +811,10 @@ struct sk_buff { __u8 active_extensions; #endif - /* fields enclosed in headers_start/headers_end are copied + /* Fields enclosed in headers group are copied * using a single memcpy() in __copy_skb_header() */ - /* private: */ - __u32 headers_start[0]; - /* public: */ + struct_group(headers, /* private: */ __u8 __pkt_type_offset[0]; @@ -921,9 +919,7 @@ struct sk_buff { u64 kcov_handle; #endif - /* private: */ - __u32 headers_end[0]; - /* public: */ + ); /* end headers group */ /* These elements must be at the end, see alloc_skb() for details. */ sk_buff_data_t tail; |