| Message ID | YuuZgsdmJK8roKLD@gondor.apana.org.au (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | af_key: Do not call xfrm_probe_algs in parallel | expand |
On Thu, Aug 04, 2022 at 06:03:46PM +0800, Herbert Xu wrote: > When namespace support was added to xfrm/afkey, it caused the > previously single-threaded call to xfrm_probe_algs to become > multi-threaded. This is buggy and needs to be fixed with a mutex. > > Reported-by: Abhishek Shah <abhishek.shah@columbia.edu> > Fixes: 283bc9f35bbb ("xfrm: Namespacify xfrm state/policy locks") > Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Applied, thanks a lot Herbert!
We can confirm we tested this patch and it prevents the race we detected in xfrm_ealg_get_byname / xfrm_probe_algs. Best, Gabe On Thu, Aug 4, 2022 at 6:03 AM Herbert Xu <herbert@gondor.apana.org.au> wrote: > > When namespace support was added to xfrm/afkey, it caused the > previously single-threaded call to xfrm_probe_algs to become > multi-threaded. This is buggy and needs to be fixed with a mutex. > > Reported-by: Abhishek Shah <abhishek.shah@columbia.edu> > Fixes: 283bc9f35bbb ("xfrm: Namespacify xfrm state/policy locks") > Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> > > diff --git a/net/key/af_key.c b/net/key/af_key.c > index fb16d7c4e1b8..20e73643b9c8 100644 > --- a/net/key/af_key.c > +++ b/net/key/af_key.c > @@ -1697,9 +1697,12 @@ static int pfkey_register(struct sock *sk, struct sk_buff *skb, const struct sad > pfk->registered |= (1<<hdr->sadb_msg_satype); > } > > + mutex_lock(&pfkey_mutex); > xfrm_probe_algs(); > > supp_skb = compose_sadb_supported(hdr, GFP_KERNEL | __GFP_ZERO); > + mutex_unlock(&pfkey_mutex); > + > if (!supp_skb) { > if (hdr->sadb_msg_satype != SADB_SATYPE_UNSPEC) > pfk->registered &= ~(1<<hdr->sadb_msg_satype); > -- > Email: Herbert Xu <herbert@gondor.apana.org.au> > Home Page: http://gondor.apana.org.au/~herbert/ > PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
diff --git a/net/key/af_key.c b/net/key/af_key.c index fb16d7c4e1b8..20e73643b9c8 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -1697,9 +1697,12 @@ static int pfkey_register(struct sock *sk, struct sk_buff *skb, const struct sad pfk->registered |= (1<<hdr->sadb_msg_satype); } + mutex_lock(&pfkey_mutex); xfrm_probe_algs(); supp_skb = compose_sadb_supported(hdr, GFP_KERNEL | __GFP_ZERO); + mutex_unlock(&pfkey_mutex); + if (!supp_skb) { if (hdr->sadb_msg_satype != SADB_SATYPE_UNSPEC) pfk->registered &= ~(1<<hdr->sadb_msg_satype);
When namespace support was added to xfrm/afkey, it caused the previously single-threaded call to xfrm_probe_algs to become multi-threaded. This is buggy and needs to be fixed with a mutex. Reported-by: Abhishek Shah <abhishek.shah@columbia.edu> Fixes: 283bc9f35bbb ("xfrm: Namespacify xfrm state/policy locks") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>