| Message ID | 20230531102805.27090-1-hbh25y@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 4d56304e5827c8cc8cc18c75343d283af7c4825c |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,v2] net/sched: flower: fix possible OOB write in fl_set_geneve_opt() | expand |
On Wed, May 31, 2023 at 06:28:04PM +0800, Hangyu Hua wrote: > If we send two TCA_FLOWER_KEY_ENC_OPTS_GENEVE packets and their total > size is 252 bytes(key->enc_opts.len = 252) then > key->enc_opts.len = opt->length = data_len / 4 = 0 when the third > TCA_FLOWER_KEY_ENC_OPTS_GENEVE packet enters fl_set_geneve_opt. This > bypasses the next bounds check and results in an out-of-bounds. > > Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") > Signed-off-by: Hangyu Hua <hbh25y@gmail.com> Reviewed-by: Simon Horman <simon.horman@corigine.com>
On 31/05/2023 11:28, Hangyu Hua wrote: > If we send two TCA_FLOWER_KEY_ENC_OPTS_GENEVE packets and their total > size is 252 bytes(key->enc_opts.len = 252) then > key->enc_opts.len = opt->length = data_len / 4 = 0 when the third > TCA_FLOWER_KEY_ENC_OPTS_GENEVE packet enters fl_set_geneve_opt. This > bypasses the next bounds check and results in an out-of-bounds. > > Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") > Signed-off-by: Hangyu Hua <hbh25y@gmail.com> Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Hello: This patch was applied to netdev/net.git (main) by Paolo Abeni <pabeni@redhat.com>: On Wed, 31 May 2023 18:28:04 +0800 you wrote: > If we send two TCA_FLOWER_KEY_ENC_OPTS_GENEVE packets and their total > size is 252 bytes(key->enc_opts.len = 252) then > key->enc_opts.len = opt->length = data_len / 4 = 0 when the third > TCA_FLOWER_KEY_ENC_OPTS_GENEVE packet enters fl_set_geneve_opt. This > bypasses the next bounds check and results in an out-of-bounds. > > Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") > Signed-off-by: Hangyu Hua <hbh25y@gmail.com> > > [...] Here is the summary with links: - [net,v2] net/sched: flower: fix possible OOB write in fl_set_geneve_opt() https://git.kernel.org/netdev/net/c/4d56304e5827 You are awesome, thank you!
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 9dbc43388e57..815c3e416bc5 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -1153,6 +1153,9 @@ static int fl_set_geneve_opt(const struct nlattr *nla, struct fl_flow_key *key, if (option_len > sizeof(struct geneve_opt)) data_len = option_len - sizeof(struct geneve_opt); + if (key->enc_opts.len > FLOW_DIS_TUN_OPTS_MAX - 4) + return -ERANGE; + opt = (struct geneve_opt *)&key->enc_opts.data[key->enc_opts.len]; memset(opt, 0xff, option_len); opt->length = data_len / 4;
If we send two TCA_FLOWER_KEY_ENC_OPTS_GENEVE packets and their total size is 252 bytes(key->enc_opts.len = 252) then key->enc_opts.len = opt->length = data_len / 4 = 0 when the third TCA_FLOWER_KEY_ENC_OPTS_GENEVE packet enters fl_set_geneve_opt. This bypasses the next bounds check and results in an out-of-bounds. Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") Signed-off-by: Hangyu Hua <hbh25y@gmail.com> --- v2: add "net" tag to title net/sched/cls_flower.c | 3 +++ 1 file changed, 3 insertions(+)