In nf_tables_commit, if nf_tables_commit_audit_alloc fails, it does not
free the adp variable.
Fix this by freeing the linked list with head adl.
backtrace:
kmalloc include/linux/slab.h:591 [inline]
kzalloc include/linux/slab.h:721 [inline]
nf_tables_commit_audit_alloc net/netfilter/nf_tables_api.c:8439 [inline]
nf_tables_commit+0x16e/0x1760 net/netfilter/nf_tables_api.c:8508
nfnetlink_rcv_batch+0x512/0xa80 net/netfilter/nfnetlink.c:562
nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]
nfnetlink_rcv+0x1fa/0x220 net/netfilter/nfnetlink.c:652
netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
netlink_unicast+0x2c7/0x3e0 net/netlink/af_netlink.c:1340
netlink_sendmsg+0x36b/0x6b0 net/netlink/af_netlink.c:1929
sock_sendmsg_nosec net/socket.c:702 [inline]
sock_sendmsg+0x56/0x80 net/socket.c:722
Reported-by: syzbot <[email protected]>
Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table")
Signed-off-by: Dongliang Mu <[email protected]>
---
net/netfilter/nf_tables_api.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 390d4466567f..7f45b291be13 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -8444,6 +8444,16 @@ static int nf_tables_commit_audit_alloc(struct list_head *adl,
return 0;
}
+static void nf_tables_commit_free(struct list_head *adl)
+{
+ struct nft_audit_data *adp, *adn;
+
+ list_for_each_entry_safe(adp, adn, adl, list) {
+ list_del(&adp->list);
+ kfree(adp);
+ }
+}
+
static void nf_tables_commit_audit_collect(struct list_head *adl,
struct nft_table *table, u32 op)
{
@@ -8508,6 +8518,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
ret = nf_tables_commit_audit_alloc(&adl, trans->ctx.table);
if (ret) {
nf_tables_commit_chain_prepare_cancel(net);
+ nf_tables_commit_free(adl);
return ret;
}
if (trans->msg_type == NFT_MSG_NEWRULE ||
@@ -8517,6 +8528,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
ret = nf_tables_commit_chain_prepare(net, chain);
if (ret < 0) {
nf_tables_commit_chain_prepare_cancel(net);
+ nf_tables_commit_free(adl);
return ret;
}
}
--
2.25.1
On Tue, Jul 13, 2021 at 11:42 AM Dongliang Mu <[email protected]> wrote:
>
> In nf_tables_commit, if nf_tables_commit_audit_alloc fails, it does not
> free the adp variable.
>
> Fix this by freeing the linked list with head adl.
>
> backtrace:
> kmalloc include/linux/slab.h:591 [inline]
> kzalloc include/linux/slab.h:721 [inline]
> nf_tables_commit_audit_alloc net/netfilter/nf_tables_api.c:8439 [inline]
> nf_tables_commit+0x16e/0x1760 net/netfilter/nf_tables_api.c:8508
> nfnetlink_rcv_batch+0x512/0xa80 net/netfilter/nfnetlink.c:562
> nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]
> nfnetlink_rcv+0x1fa/0x220 net/netfilter/nfnetlink.c:652
> netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
> netlink_unicast+0x2c7/0x3e0 net/netlink/af_netlink.c:1340
> netlink_sendmsg+0x36b/0x6b0 net/netlink/af_netlink.c:1929
> sock_sendmsg_nosec net/socket.c:702 [inline]
> sock_sendmsg+0x56/0x80 net/socket.c:722
>
> Reported-by: syzbot <[email protected]>
As far as I see, the more default way is to reference to syzbot by:
Reported-by: syzbot+[[20-letter hex reference]]@syzkaller.appspotmail.com
as in for example:
Reported-by: [email protected]
A rough count says that format above is used 1300 times, whereas
Reported-by: syzbot <[email protected]>
is only used about 330 times.
Lukas
> Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table")
> Signed-off-by: Dongliang Mu <[email protected]>
> ---
> net/netfilter/nf_tables_api.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
> index 390d4466567f..7f45b291be13 100644
> --- a/net/netfilter/nf_tables_api.c
> +++ b/net/netfilter/nf_tables_api.c
> @@ -8444,6 +8444,16 @@ static int nf_tables_commit_audit_alloc(struct list_head *adl,
> return 0;
> }
>
> +static void nf_tables_commit_free(struct list_head *adl)
> +{
> + struct nft_audit_data *adp, *adn;
> +
> + list_for_each_entry_safe(adp, adn, adl, list) {
> + list_del(&adp->list);
> + kfree(adp);
> + }
> +}
> +
> static void nf_tables_commit_audit_collect(struct list_head *adl,
> struct nft_table *table, u32 op)
> {
> @@ -8508,6 +8518,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
> ret = nf_tables_commit_audit_alloc(&adl, trans->ctx.table);
> if (ret) {
> nf_tables_commit_chain_prepare_cancel(net);
> + nf_tables_commit_free(adl);
> return ret;
> }
> if (trans->msg_type == NFT_MSG_NEWRULE ||
> @@ -8517,6 +8528,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
> ret = nf_tables_commit_chain_prepare(net, chain);
> if (ret < 0) {
> nf_tables_commit_chain_prepare_cancel(net);
> + nf_tables_commit_free(adl);
> return ret;
> }
> }
> --
> 2.25.1
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller/20210713094158.450434-1-mudongliangabcd%40gmail.com.
On Tue, Jul 13, 2021 at 7:47 PM Lukas Bulwahn <[email protected]> wrote:
>
> On Tue, Jul 13, 2021 at 11:42 AM Dongliang Mu <[email protected]> wrote:
> >
> > In nf_tables_commit, if nf_tables_commit_audit_alloc fails, it does not
> > free the adp variable.
> >
> > Fix this by freeing the linked list with head adl.
> >
> > backtrace:
> > kmalloc include/linux/slab.h:591 [inline]
> > kzalloc include/linux/slab.h:721 [inline]
> > nf_tables_commit_audit_alloc net/netfilter/nf_tables_api.c:8439 [inline]
> > nf_tables_commit+0x16e/0x1760 net/netfilter/nf_tables_api.c:8508
> > nfnetlink_rcv_batch+0x512/0xa80 net/netfilter/nfnetlink.c:562
> > nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]
> > nfnetlink_rcv+0x1fa/0x220 net/netfilter/nfnetlink.c:652
> > netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
> > netlink_unicast+0x2c7/0x3e0 net/netlink/af_netlink.c:1340
> > netlink_sendmsg+0x36b/0x6b0 net/netlink/af_netlink.c:1929
> > sock_sendmsg_nosec net/socket.c:702 [inline]
> > sock_sendmsg+0x56/0x80 net/socket.c:722
> >
> > Reported-by: syzbot <[email protected]>
>
> As far as I see, the more default way is to reference to syzbot by:
>
> Reported-by: syzbot+[[20-letter hex reference]]@syzkaller.appspotmail.com
>
Hi Lukas,
this bug is not listed on the syzbot dashboard. I found this bug by
setting up a local syzkaller instance, so I only list syzbot other
than concrete syzbot id.
best regards,
Dongliang Mu
> as in for example:
>
> Reported-by: [email protected]
>
> A rough count says that format above is used 1300 times, whereas
>
> Reported-by: syzbot <[email protected]>
>
> is only used about 330 times.
>
>
> Lukas
>
> > Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table")
> > Signed-off-by: Dongliang Mu <[email protected]>
> > ---
> > net/netfilter/nf_tables_api.c | 12 ++++++++++++
> > 1 file changed, 12 insertions(+)
> >
> > diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
> > index 390d4466567f..7f45b291be13 100644
> > --- a/net/netfilter/nf_tables_api.c
> > +++ b/net/netfilter/nf_tables_api.c
> > @@ -8444,6 +8444,16 @@ static int nf_tables_commit_audit_alloc(struct list_head *adl,
> > return 0;
> > }
> >
> > +static void nf_tables_commit_free(struct list_head *adl)
> > +{
> > + struct nft_audit_data *adp, *adn;
> > +
> > + list_for_each_entry_safe(adp, adn, adl, list) {
> > + list_del(&adp->list);
> > + kfree(adp);
> > + }
> > +}
> > +
> > static void nf_tables_commit_audit_collect(struct list_head *adl,
> > struct nft_table *table, u32 op)
> > {
> > @@ -8508,6 +8518,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
> > ret = nf_tables_commit_audit_alloc(&adl, trans->ctx.table);
> > if (ret) {
> > nf_tables_commit_chain_prepare_cancel(net);
> > + nf_tables_commit_free(adl);
> > return ret;
> > }
> > if (trans->msg_type == NFT_MSG_NEWRULE ||
> > @@ -8517,6 +8528,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
> > ret = nf_tables_commit_chain_prepare(net, chain);
> > if (ret < 0) {
> > nf_tables_commit_chain_prepare_cancel(net);
> > + nf_tables_commit_free(adl);
> > return ret;
> > }
> > }
> > --
> > 2.25.1
> >
> > --
> > You received this message because you are subscribed to the Google Groups "syzkaller" group.
> > To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller/20210713094158.450434-1-mudongliangabcd%40gmail.com.
On Tue, Jul 13, 2021 at 1:52 PM Dongliang Mu <[email protected]> wrote:
>
> On Tue, Jul 13, 2021 at 7:47 PM Lukas Bulwahn <[email protected]> wrote:
> >
> > On Tue, Jul 13, 2021 at 11:42 AM Dongliang Mu <[email protected]> wrote:
> > >
> > >
> > > Reported-by: syzbot <[email protected]>
> >
> > As far as I see, the more default way is to reference to syzbot by:
> >
> > Reported-by: syzbot+[[20-letter hex reference]]@syzkaller.appspotmail.com
> >
>
> Hi Lukas,
>
> this bug is not listed on the syzbot dashboard. I found this bug by
> setting up a local syzkaller instance, so I only list syzbot other
> than concrete syzbot id.
>
I see. Thanks for your explanation.
Lukas