diff options
| author | Cong Wang <xiyou.wangcong@gmail.com> | 2019-12-06 06:39:02 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-12-17 22:35:51 +0300 |
| commit | f7654ebe928d46bd540e0305dbdcc57752de424c (patch) | |
| tree | b45755134051b490df163dca7c855b344af76b74 /net | |
| parent | 4f579272b0e06943adabfab13d004e65e356a622 (diff) | |
| download | linux-f7654ebe928d46bd540e0305dbdcc57752de424c.tar.xz | |
gre: refetch erspan header from skb->data after pskb_may_pull()
[ Upstream commit 0e4940928c26527ce8f97237fef4c8a91cd34207 ]
After pskb_may_pull() we should always refetch the header
pointers from the skb->data in case it got reallocated.
In gre_parse_header(), the erspan header is still fetched
from the 'options' pointer which is fetched before
pskb_may_pull().
Found this during code review of a KMSAN bug report.
Fixes: cb73ee40b1b3 ("net: ip_gre: use erspan key field for tunnel lookup")
Cc: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Acked-by: William Tu <u9012063@gmail.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/gre_demux.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv4/gre_demux.c b/net/ipv4/gre_demux.c index 511b32ea2533..0eb4bfa2332c 100644 --- a/net/ipv4/gre_demux.c +++ b/net/ipv4/gre_demux.c @@ -132,7 +132,7 @@ int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, if (!pskb_may_pull(skb, nhs + hdr_len + sizeof(*ershdr))) return -EINVAL; - ershdr = (struct erspan_base_hdr *)options; + ershdr = (struct erspan_base_hdr *)(skb->data + nhs + hdr_len); tpi->key = cpu_to_be32(get_session_id(ershdr)); } |