| Message ID | 20240918140602.18644-1-jiwonaid0@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 0cbfd45fbcf0cb26d85c981b91c62fe73cdee01c |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,v3] bonding: Fix unnecessary warnings and logs from bond_xdp_get_xmit_slave() | expand |
On 18/09/2024 17:06, Jiwon Kim wrote: > syzbot reported a WARNING in bond_xdp_get_xmit_slave. To reproduce > this[1], one bond device (bond1) has xdpdrv, which increases > bpf_master_redirect_enabled_key. Another bond device (bond0) which is > unsupported by XDP but its slave (veth3) has xdpgeneric that returns > XDP_TX. This triggers WARN_ON_ONCE() from the xdp_master_redirect(). > To reduce unnecessary warnings and improve log management, we need to > delete the WARN_ON_ONCE() and add ratelimit to the netdev_err(). > > [1] Steps to reproduce: > # Needs tx_xdp with return XDP_TX; > ip l add veth0 type veth peer veth1 > ip l add veth3 type veth peer veth4 > ip l add bond0 type bond mode 6 # BOND_MODE_ALB, unsupported by XDP > ip l add bond1 type bond # BOND_MODE_ROUNDROBIN by default > ip l set veth0 master bond1 > ip l set bond1 up > # Increases bpf_master_redirect_enabled_key > ip l set dev bond1 xdpdrv object tx_xdp.o section xdp_tx > ip l set veth3 master bond0 > ip l set bond0 up > ip l set veth4 up > # Triggers WARN_ON_ONCE() from the xdp_master_redirect() > ip l set veth3 xdpgeneric object tx_xdp.o section xdp_tx > > Reported-by: syzbot+c187823a52ed505b2257@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=c187823a52ed505b2257 > Fixes: 9e2ee5c7e7c3 ("net, bonding: Add XDP support to the bonding driver") > Signed-off-by: Jiwon Kim <jiwonaid0@gmail.com> > --- > v3: Fix subject and description > v2: Change the patch to fix bond_xdp_get_xmit_slave > --- > drivers/net/bonding/bond_main.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c > index b560644ee1b1..b1bffd8e9a95 100644 > --- a/drivers/net/bonding/bond_main.c > +++ b/drivers/net/bonding/bond_main.c > @@ -5610,9 +5610,9 @@ bond_xdp_get_xmit_slave(struct net_device *bond_dev, struct xdp_buff *xdp) > break; > > default: > - /* Should never happen. Mode guarded by bond_xdp_check() */ > - netdev_err(bond_dev, "Unknown bonding mode %d for xdp xmit\n", BOND_MODE(bond)); > - WARN_ON_ONCE(1); > + if (net_ratelimit()) > + netdev_err(bond_dev, "Unknown bonding mode %d for xdp xmit\n", > + BOND_MODE(bond)); > return NULL; > } > Looks good to me, but next time wait 1 day before reposting another version. Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
On 9/18/24 16:06, Jiwon Kim wrote: > syzbot reported a WARNING in bond_xdp_get_xmit_slave. To reproduce > this[1], one bond device (bond1) has xdpdrv, which increases > bpf_master_redirect_enabled_key. Another bond device (bond0) which is > unsupported by XDP but its slave (veth3) has xdpgeneric that returns > XDP_TX. This triggers WARN_ON_ONCE() from the xdp_master_redirect(). > To reduce unnecessary warnings and improve log management, we need to > delete the WARN_ON_ONCE() and add ratelimit to the netdev_err(). > > [1] Steps to reproduce: > # Needs tx_xdp with return XDP_TX; > ip l add veth0 type veth peer veth1 > ip l add veth3 type veth peer veth4 > ip l add bond0 type bond mode 6 # BOND_MODE_ALB, unsupported by XDP > ip l add bond1 type bond # BOND_MODE_ROUNDROBIN by default > ip l set veth0 master bond1 > ip l set bond1 up > # Increases bpf_master_redirect_enabled_key > ip l set dev bond1 xdpdrv object tx_xdp.o section xdp_tx > ip l set veth3 master bond0 > ip l set bond0 up > ip l set veth4 up > # Triggers WARN_ON_ONCE() from the xdp_master_redirect() > ip l set veth3 xdpgeneric object tx_xdp.o section xdp_tx > > Reported-by: syzbot+c187823a52ed505b2257@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=c187823a52ed505b2257 > Fixes: 9e2ee5c7e7c3 ("net, bonding: Add XDP support to the bonding driver") > Signed-off-by: Jiwon Kim <jiwonaid0@gmail.com> Isn't the above issue completely addressed by explicitly checking for bond->prog in bond_xdp_get_xmit_slave()? Or would that broke some use-case? Thanks, Paolo
On 9/24/24 13:20, Paolo Abeni wrote: > On 9/18/24 16:06, Jiwon Kim wrote: >> syzbot reported a WARNING in bond_xdp_get_xmit_slave. To reproduce >> this[1], one bond device (bond1) has xdpdrv, which increases >> bpf_master_redirect_enabled_key. Another bond device (bond0) which is >> unsupported by XDP but its slave (veth3) has xdpgeneric that returns >> XDP_TX. This triggers WARN_ON_ONCE() from the xdp_master_redirect(). >> To reduce unnecessary warnings and improve log management, we need to >> delete the WARN_ON_ONCE() and add ratelimit to the netdev_err(). >> >> [1] Steps to reproduce: >> # Needs tx_xdp with return XDP_TX; >> ip l add veth0 type veth peer veth1 >> ip l add veth3 type veth peer veth4 >> ip l add bond0 type bond mode 6 # BOND_MODE_ALB, unsupported by XDP >> ip l add bond1 type bond # BOND_MODE_ROUNDROBIN by default >> ip l set veth0 master bond1 >> ip l set bond1 up >> # Increases bpf_master_redirect_enabled_key >> ip l set dev bond1 xdpdrv object tx_xdp.o section xdp_tx >> ip l set veth3 master bond0 >> ip l set bond0 up >> ip l set veth4 up >> # Triggers WARN_ON_ONCE() from the xdp_master_redirect() >> ip l set veth3 xdpgeneric object tx_xdp.o section xdp_tx >> >> Reported-by: syzbot+c187823a52ed505b2257@syzkaller.appspotmail.com >> Closes: https://syzkaller.appspot.com/bug?extid=c187823a52ed505b2257 >> Fixes: 9e2ee5c7e7c3 ("net, bonding: Add XDP support to the bonding driver") >> Signed-off-by: Jiwon Kim <jiwonaid0@gmail.com> > > Isn't the above issue completely addressed by explicitly checking for > bond->prog in bond_xdp_get_xmit_slave()? Or would that broke some use-case? > > Thanks, > > Paolo > There isn't much difference with this patch, bond_xdp_get_xmit_slave() always returns either a slave or NULL, either way you'd return NULL. It does have a potential to break some weird setup, but I can't currently come up with one where bond_xdp_get_xmit_slave is used and xdp_prog is not set, so I don't have a preference about which way to fix it. :) Cheers, Nik
Hello: This patch was applied to netdev/net.git (main) by Paolo Abeni <pabeni@redhat.com>: On Wed, 18 Sep 2024 14:06:02 +0000 you wrote: > syzbot reported a WARNING in bond_xdp_get_xmit_slave. To reproduce > this[1], one bond device (bond1) has xdpdrv, which increases > bpf_master_redirect_enabled_key. Another bond device (bond0) which is > unsupported by XDP but its slave (veth3) has xdpgeneric that returns > XDP_TX. This triggers WARN_ON_ONCE() from the xdp_master_redirect(). > To reduce unnecessary warnings and improve log management, we need to > delete the WARN_ON_ONCE() and add ratelimit to the netdev_err(). > > [...] Here is the summary with links: - [net,v3] bonding: Fix unnecessary warnings and logs from bond_xdp_get_xmit_slave() https://git.kernel.org/netdev/net/c/0cbfd45fbcf0 You are awesome, thank you!
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index b560644ee1b1..b1bffd8e9a95 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -5610,9 +5610,9 @@ bond_xdp_get_xmit_slave(struct net_device *bond_dev, struct xdp_buff *xdp) break; default: - /* Should never happen. Mode guarded by bond_xdp_check() */ - netdev_err(bond_dev, "Unknown bonding mode %d for xdp xmit\n", BOND_MODE(bond)); - WARN_ON_ONCE(1); + if (net_ratelimit()) + netdev_err(bond_dev, "Unknown bonding mode %d for xdp xmit\n", + BOND_MODE(bond)); return NULL; }
syzbot reported a WARNING in bond_xdp_get_xmit_slave. To reproduce this[1], one bond device (bond1) has xdpdrv, which increases bpf_master_redirect_enabled_key. Another bond device (bond0) which is unsupported by XDP but its slave (veth3) has xdpgeneric that returns XDP_TX. This triggers WARN_ON_ONCE() from the xdp_master_redirect(). To reduce unnecessary warnings and improve log management, we need to delete the WARN_ON_ONCE() and add ratelimit to the netdev_err(). [1] Steps to reproduce: # Needs tx_xdp with return XDP_TX; ip l add veth0 type veth peer veth1 ip l add veth3 type veth peer veth4 ip l add bond0 type bond mode 6 # BOND_MODE_ALB, unsupported by XDP ip l add bond1 type bond # BOND_MODE_ROUNDROBIN by default ip l set veth0 master bond1 ip l set bond1 up # Increases bpf_master_redirect_enabled_key ip l set dev bond1 xdpdrv object tx_xdp.o section xdp_tx ip l set veth3 master bond0 ip l set bond0 up ip l set veth4 up # Triggers WARN_ON_ONCE() from the xdp_master_redirect() ip l set veth3 xdpgeneric object tx_xdp.o section xdp_tx Reported-by: syzbot+c187823a52ed505b2257@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=c187823a52ed505b2257 Fixes: 9e2ee5c7e7c3 ("net, bonding: Add XDP support to the bonding driver") Signed-off-by: Jiwon Kim <jiwonaid0@gmail.com> --- v3: Fix subject and description v2: Change the patch to fix bond_xdp_get_xmit_slave --- drivers/net/bonding/bond_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)