* [PATCH v2] audit: fix memory leak in nf_tables_commit
@ 2021-07-13 13:03 Dongliang Mu
2021-07-13 13:20 ` Florian Westphal
0 siblings, 1 reply; 5+ messages in thread
From: Dongliang Mu @ 2021-07-13 13:03 UTC (permalink / raw)
To: Pablo Neira Ayuso, Jozsef Kadlecsik, Florian Westphal,
David S. Miller, Jakub Kicinski, Richard Guy Briggs, Paul Moore
Cc: Dongliang Mu, syzbot, kernel test robot, netfilter-devel,
coreteam, netdev, linux-kernel
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 <syzkaller@googlegroups.com>
Reported-by: kernel test robot <lkp@intel.com>
Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
---
v1->v2: fix the compile issue
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
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v2] audit: fix memory leak in nf_tables_commit
2021-07-13 13:03 [PATCH v2] audit: fix memory leak in nf_tables_commit Dongliang Mu
@ 2021-07-13 13:20 ` Florian Westphal
2021-07-13 14:40 ` Dongliang Mu
0 siblings, 1 reply; 5+ messages in thread
From: Florian Westphal @ 2021-07-13 13:20 UTC (permalink / raw)
To: Dongliang Mu
Cc: Pablo Neira Ayuso, Jozsef Kadlecsik, Florian Westphal,
David S. Miller, Jakub Kicinski, Richard Guy Briggs, Paul Moore,
syzbot, kernel test robot, netfilter-devel, coreteam, netdev,
linux-kernel
Dongliang Mu <mudongliangabcd@gmail.com> 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 <syzkaller@googlegroups.com>
> Reported-by: kernel test robot <lkp@intel.com>
> Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table")
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> ---
> v1->v2: fix the compile issue
> 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)
nf_tables_commit_audit_free?
Aside from that, there should be a followup patch (for nf-next),
adding empty inline functions in case of CONFIG_AUDITSYSCALL=n.
Right now it does pointless aggregation for the AUDIT=n case.
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH v2] audit: fix memory leak in nf_tables_commit
2021-07-13 13:20 ` Florian Westphal
@ 2021-07-13 14:40 ` Dongliang Mu
2021-07-13 15:31 ` Florian Westphal
0 siblings, 1 reply; 5+ messages in thread
From: Dongliang Mu @ 2021-07-13 14:40 UTC (permalink / raw)
To: Florian Westphal
Cc: Pablo Neira Ayuso, Jozsef Kadlecsik, David S. Miller,
Jakub Kicinski, Richard Guy Briggs, Paul Moore, syzbot,
kernel test robot, netfilter-devel, coreteam,
open list:NETWORKING [GENERAL],
linux-kernel
On Tue, Jul 13, 2021 at 9:21 PM Florian Westphal <fw@strlen.de> wrote:
>
> Dongliang Mu <mudongliangabcd@gmail.com> 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 <syzkaller@googlegroups.com>
> > Reported-by: kernel test robot <lkp@intel.com>
> > Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table")
> > Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> > ---
> > v1->v2: fix the compile issue
> > 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)
>
> nf_tables_commit_audit_free?
What do you mean? Modify the name of newly added function to
nf_tables_commit_audit_free?
>
> Aside from that, there should be a followup patch (for nf-next),
> adding empty inline functions in case of CONFIG_AUDITSYSCALL=n.
I see. I prefer to send them (two implementations of the newly added
function) in version v2.
>
> Right now it does pointless aggregation for the AUDIT=n case.
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH v2] audit: fix memory leak in nf_tables_commit
2021-07-13 14:40 ` Dongliang Mu
@ 2021-07-13 15:31 ` Florian Westphal
2021-07-14 2:18 ` Dongliang Mu
0 siblings, 1 reply; 5+ messages in thread
From: Florian Westphal @ 2021-07-13 15:31 UTC (permalink / raw)
To: Dongliang Mu
Cc: Florian Westphal, Pablo Neira Ayuso, Jozsef Kadlecsik,
David S. Miller, Jakub Kicinski, Richard Guy Briggs, Paul Moore,
syzbot, kernel test robot, netfilter-devel, coreteam,
open list:NETWORKING [GENERAL],
linux-kernel
Dongliang Mu <mudongliangabcd@gmail.com> wrote:
> > > +static void nf_tables_commit_free(struct list_head *adl)
> >
> > nf_tables_commit_audit_free?
>
> What do you mean? Modify the name of newly added function to
> nf_tables_commit_audit_free?
Yes, this function is audit related, and it does the inverse
of existing '...audit_alloc'.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] audit: fix memory leak in nf_tables_commit
2021-07-13 15:31 ` Florian Westphal
@ 2021-07-14 2:18 ` Dongliang Mu
0 siblings, 0 replies; 5+ messages in thread
From: Dongliang Mu @ 2021-07-14 2:18 UTC (permalink / raw)
To: Florian Westphal
Cc: Pablo Neira Ayuso, Jozsef Kadlecsik, David S. Miller,
Jakub Kicinski, Richard Guy Briggs, Paul Moore, syzbot,
kernel test robot, netfilter-devel, coreteam,
open list:NETWORKING [GENERAL],
linux-kernel
On Tue, Jul 13, 2021 at 11:31 PM Florian Westphal <fw@strlen.de> wrote:
>
> Dongliang Mu <mudongliangabcd@gmail.com> wrote:
> > > > +static void nf_tables_commit_free(struct list_head *adl)
> > >
> > > nf_tables_commit_audit_free?
> >
> > What do you mean? Modify the name of newly added function to
> > nf_tables_commit_audit_free?
>
> Yes, this function is audit related, and it does the inverse
> of existing '...audit_alloc'.
Hi Florian,
I double-check the patch, and it seems there is no need to send a
followup patch (nf-next).
I will send a v3 patch with the new function name.
Best regards
Dongliang Mu
^ permalink raw reply [flat|nested] 5+ messages in thread
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2021-07-13 13:03 [PATCH v2] audit: fix memory leak in nf_tables_commit Dongliang Mu
2021-07-13 13:20 ` Florian Westphal
2021-07-13 14:40 ` Dongliang Mu
2021-07-13 15:31 ` Florian Westphal
2021-07-14 2:18 ` Dongliang Mu
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