Hi Eric, [auto build test WARNING on net/master]
url: https://github.com/0day-ci/linux/commits/Eric-Dumazet/packet-avoid-panic-in-packet_getsockopt/20171021-003615 reproduce: # apt-get install sparse make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) vim +3936 net/packet/af_packet.c 3845 3846 static int packet_getsockopt(struct socket *sock, int level, int optname, 3847 char __user *optval, int __user *optlen) 3848 { 3849 int len; 3850 int val, lv = sizeof(val); 3851 struct sock *sk = sock->sk; 3852 struct packet_sock *po = pkt_sk(sk); 3853 void *data = &val; 3854 union tpacket_stats_u st; 3855 struct tpacket_rollover_stats rstats; 3856 struct packet_rollover *rollover; 3857 3858 if (level != SOL_PACKET) 3859 return -ENOPROTOOPT; 3860 3861 if (get_user(len, optlen)) 3862 return -EFAULT; 3863 3864 if (len < 0) 3865 return -EINVAL; 3866 3867 switch (optname) { 3868 case PACKET_STATISTICS: 3869 spin_lock_bh(&sk->sk_receive_queue.lock); 3870 memcpy(&st, &po->stats, sizeof(st)); 3871 memset(&po->stats, 0, sizeof(po->stats)); 3872 spin_unlock_bh(&sk->sk_receive_queue.lock); 3873 3874 if (po->tp_version == TPACKET_V3) { 3875 lv = sizeof(struct tpacket_stats_v3); 3876 st.stats3.tp_packets += st.stats3.tp_drops; 3877 data = &st.stats3; 3878 } else { 3879 lv = sizeof(struct tpacket_stats); 3880 st.stats1.tp_packets += st.stats1.tp_drops; 3881 data = &st.stats1; 3882 } 3883 3884 break; 3885 case PACKET_AUXDATA: 3886 val = po->auxdata; 3887 break; 3888 case PACKET_ORIGDEV: 3889 val = po->origdev; 3890 break; 3891 case PACKET_VNET_HDR: 3892 val = po->has_vnet_hdr; 3893 break; 3894 case PACKET_VERSION: 3895 val = po->tp_version; 3896 break; 3897 case PACKET_HDRLEN: 3898 if (len > sizeof(int)) 3899 len = sizeof(int); 3900 if (len < sizeof(int)) 3901 return -EINVAL; 3902 if (copy_from_user(&val, optval, len)) 3903 return -EFAULT; 3904 switch (val) { 3905 case TPACKET_V1: 3906 val = sizeof(struct tpacket_hdr); 3907 break; 3908 case TPACKET_V2: 3909 val = sizeof(struct tpacket2_hdr); 3910 break; 3911 case TPACKET_V3: 3912 val = sizeof(struct tpacket3_hdr); 3913 break; 3914 default: 3915 return -EINVAL; 3916 } 3917 break; 3918 case PACKET_RESERVE: 3919 val = po->tp_reserve; 3920 break; 3921 case PACKET_LOSS: 3922 val = po->tp_loss; 3923 break; 3924 case PACKET_TIMESTAMP: 3925 val = po->tp_tstamp; 3926 break; 3927 case PACKET_FANOUT: 3928 val = (po->fanout ? 3929 ((u32)po->fanout->id | 3930 ((u32)po->fanout->type << 16) | 3931 ((u32)po->fanout->flags << 24)) : 3932 0); 3933 break; 3934 case PACKET_ROLLOVER_STATS: 3935 rcu_read_lock(); > 3936 rollover = rcu_dereference(po->rollover); 3937 if (rollover) { 3938 rstats.tp_all = atomic_long_read(&rollover->num); 3939 rstats.tp_huge = atomic_long_read(&rollover->num_huge); 3940 rstats.tp_failed = atomic_long_read(&rollover->num_failed); 3941 data = &rstats; 3942 lv = sizeof(rstats); 3943 } 3944 rcu_read_unlock(); 3945 if (!rollover) 3946 return -EINVAL; 3947 break; 3948 case PACKET_TX_HAS_OFF: 3949 val = po->tp_tx_has_off; 3950 break; 3951 case PACKET_QDISC_BYPASS: 3952 val = packet_use_direct_xmit(po); 3953 break; 3954 default: 3955 return -ENOPROTOOPT; 3956 } 3957 3958 if (len > lv) 3959 len = lv; 3960 if (put_user(len, optlen)) 3961 return -EFAULT; 3962 if (copy_to_user(optval, data, len)) 3963 return -EFAULT; 3964 return 0; 3965 } 3966 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
