Re: [PATCH] net: tun: set tun->dev->addr_len during TUNSETLINK processing
On Tue, Apr 06, 2021 at 07:26:29PM +0200, Eric Dumazet wrote: > > > On 4/5/21 1:35 PM, Phillip Potter wrote: > > When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len > > to match the appropriate type, using new tun_get_addr_len utility function > > which returns appropriate address length for given type. Fixes a > > KMSAN-found uninit-value bug reported by syzbot at: > > https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51 > > > > Reported-by: syzbot+001516d86dbe88862...@syzkaller.appspotmail.com > > Signed-off-by: Phillip Potter > > --- > > Please give credits to people who helped. > > You could have : > > Suggested-by: Eric Dumazet > > Or > Diagnosed-by: Eric Dumazet > > Or at least CCed me :/ > Dear Eric, Please accept my apology for this oversight. It certainly wasn't intentional on my part, and entirely down to inexperience. I will send the patch again with Diagnosed-by. Regards, Phil
Re: [PATCH] net: tun: set tun->dev->addr_len during TUNSETLINK processing
On 4/5/21 1:35 PM, Phillip Potter wrote: > When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len > to match the appropriate type, using new tun_get_addr_len utility function > which returns appropriate address length for given type. Fixes a > KMSAN-found uninit-value bug reported by syzbot at: > https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51 > > Reported-by: syzbot+001516d86dbe88862...@syzkaller.appspotmail.com > Signed-off-by: Phillip Potter > --- Please give credits to people who helped. You could have : Suggested-by: Eric Dumazet Or Diagnosed-by: Eric Dumazet Or at least CCed me :/
Re: [PATCH] net: tun: set tun->dev->addr_len during TUNSETLINK processing
On Mon, Apr 05, 2021 at 02:59:21PM -0700, David Miller wrote: > From: Phillip Potter > Date: Mon, 5 Apr 2021 12:35:55 +0100 > > > When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len > > to match the appropriate type, using new tun_get_addr_len utility function > > which returns appropriate address length for given type. Fixes a > > KMSAN-found uninit-value bug reported by syzbot at: > > https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51 > > > > Reported-by: syzbot+001516d86dbe88862...@syzkaller.appspotmail.com > > Signed-off-by: Phillip Potter > > --- > > drivers/net/tun.c | 48 +++ > > 1 file changed, 48 insertions(+) > > > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > > index 978ac0981d16..56c26339ee3b 100644 > > --- a/drivers/net/tun.c > > +++ b/drivers/net/tun.c > > @@ -69,6 +69,14 @@ > > #include > > #include > > #include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > > > #include > > #include > > @@ -2925,6 +2933,45 @@ static int tun_set_ebpf(struct tun_struct *tun, > > struct tun_prog __rcu **prog_p, > > return __tun_set_ebpf(tun, prog_p, prog); > > } > > > > +/* Return correct value for tun->dev->addr_len based on tun->dev->type. */ > > +static inline unsigned char tun_get_addr_len(unsigned short type) > > +{ > > Please do not use inline in foo.c files, let the compiler decide. > > Thanks. Dear David, Thank you for the feedback, I will resend. Regards, Phil
Re: [PATCH] net: tun: set tun->dev->addr_len during TUNSETLINK processing
From: Phillip Potter Date: Mon, 5 Apr 2021 12:35:55 +0100 > When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len > to match the appropriate type, using new tun_get_addr_len utility function > which returns appropriate address length for given type. Fixes a > KMSAN-found uninit-value bug reported by syzbot at: > https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51 > > Reported-by: syzbot+001516d86dbe88862...@syzkaller.appspotmail.com > Signed-off-by: Phillip Potter > --- > drivers/net/tun.c | 48 +++ > 1 file changed, 48 insertions(+) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index 978ac0981d16..56c26339ee3b 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -69,6 +69,14 @@ > #include > #include > #include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > > #include > #include > @@ -2925,6 +2933,45 @@ static int tun_set_ebpf(struct tun_struct *tun, struct > tun_prog __rcu **prog_p, > return __tun_set_ebpf(tun, prog_p, prog); > } > > +/* Return correct value for tun->dev->addr_len based on tun->dev->type. */ > +static inline unsigned char tun_get_addr_len(unsigned short type) > +{ Please do not use inline in foo.c files, let the compiler decide. Thanks.
[PATCH] net: tun: set tun->dev->addr_len during TUNSETLINK processing
When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len to match the appropriate type, using new tun_get_addr_len utility function which returns appropriate address length for given type. Fixes a KMSAN-found uninit-value bug reported by syzbot at: https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51 Reported-by: syzbot+001516d86dbe88862...@syzkaller.appspotmail.com Signed-off-by: Phillip Potter --- drivers/net/tun.c | 48 +++ 1 file changed, 48 insertions(+) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 978ac0981d16..56c26339ee3b 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -69,6 +69,14 @@ #include #include #include +#include +#include +#include +#include +#include +#include +#include +#include #include #include @@ -2925,6 +2933,45 @@ static int tun_set_ebpf(struct tun_struct *tun, struct tun_prog __rcu **prog_p, return __tun_set_ebpf(tun, prog_p, prog); } +/* Return correct value for tun->dev->addr_len based on tun->dev->type. */ +static inline unsigned char tun_get_addr_len(unsigned short type) +{ + switch (type) { + case ARPHRD_IP6GRE: + case ARPHRD_TUNNEL6: + return sizeof(struct in6_addr); + case ARPHRD_IPGRE: + case ARPHRD_TUNNEL: + case ARPHRD_SIT: + return 4; + case ARPHRD_ETHER: + return ETH_ALEN; + case ARPHRD_IEEE802154: + case ARPHRD_IEEE802154_MONITOR: + return IEEE802154_EXTENDED_ADDR_LEN; + case ARPHRD_PHONET_PIPE: + case ARPHRD_PPP: + case ARPHRD_NONE: + return 0; + case ARPHRD_6LOWPAN: + return EUI64_ADDR_LEN; + case ARPHRD_FDDI: + return FDDI_K_ALEN; + case ARPHRD_HIPPI: + return HIPPI_ALEN; + case ARPHRD_IEEE802: + return FC_ALEN; + case ARPHRD_ROSE: + return ROSE_ADDR_LEN; + case ARPHRD_NETROM: + return AX25_ADDR_LEN; + case ARPHRD_LOCALTLK: + return LTALK_ALEN; + default: + return 0; + } +} + static long __tun_chr_ioctl(struct file *file, unsigned int cmd, unsigned long arg, int ifreq_len) { @@ -3088,6 +3135,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } tun->dev->type = (int) arg; + tun->dev->addr_len = tun_get_addr_len(tun->dev->type); netif_info(tun, drv, tun->dev, "linktype set to %d\n", tun->dev->type); call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, -- 2.30.2