/* * netsniff-ng - the packet sniffing beast * Copyright 2009, 2010 Daniel Borkmann. * Copyright 2010 Emmanuel Roullit. * Subject to the GPL, version 2. */ #include #include #include /* for ntohs() */ #include /* for inet_ntop() */ #include "proto.h" #include "protos.h" #include "csum.h" #include "dissector_eth.h" #include "ipv6.h" #include "geoip.h" #include "pkt_buff.h" extern void ipv6(struct pkt_buff *pkt); extern void ipv6_less(struct pkt_buff *pkt); void ipv6(struct pkt_buff *pkt) { uint8_t traffic_class; uint32_t flow_label; char src_ip[INET6_ADDRSTRLEN]; char dst_ip[INET6_ADDRSTRLEN]; struct ipv6hdr *ip = (struct ipv6hdr *) pkt_pull(pkt, sizeof(*ip)); struct sockaddr_in6 sas, sad; const char *city, *region, *country; if (ip == NULL) return; traffic_class = (ip->priority << 4) | ((ip->flow_lbl[0] & 0xF0) >> 4); flow_label = ((ip->flow_lbl[0] & 0x0F) << 8) | (ip->flow_lbl[1] << 4) | ip->flow_lbl[2]; inet_ntop(AF_INET6, &ip->saddr, src_ip, sizeof(src_ip)); inet_ntop(AF_INET6, &ip->daddr, dst_ip, sizeof(dst_ip)); tprintf(" [ IPv6 "); tprintf("Addr (%s => %s), ", src_ip, dst_ip); tprintf("Version (%u), ", ip->version); tprintf("TrafficClass (%u), ", traffic_class); tprintf("FlowLabel (%u), ", flow_label); tprintf("Len (%u), ", ntohs(ip->payload_len)); tprintf("NextHdr (%u), ", ip->nexthdr); tprintf("HopLimit (%u)", ip->hop_limit); tprintf(" ]\n"); memset(&sas, 0, sizeof(sas)); sas.sin6_family = PF_INET6; memcpy(&sas.sin6_addr, &ip->saddr, sizeof(ip->saddr)); memset(&sad, 0, sizeof(sad)); sad.sin6_family = PF_INET6; memcpy(&sad.sin6_addr, &ip->daddr, sizeof(ip->daddr)); if (geoip_working()) { tprintf("\t[ Geo ("); if ((country = geoip6_country_name(sas))) { tprintf("%s", country); if ((region = geoip6_region_name(sas))) tprintf(" / %s", region); if ((city = geoip6_city_name(sas))) tprintf(" / %s", city); } else { tprintf("local"); } tprintf(" => "); if ((country = geoip6_country_name(sad))) { tprintf("%s", country); if ((region = geoip6_region_name(sad))) tprintf(" / %s", region); if ((city = geoip6_city_name(sad))) tprintf(" / %s", city); } else { tprintf("local"); } tprintf(") ]\n"); } pkt_set_proto(pkt, ð_lay3, ip->nexthdr); } void ipv6_less(struct pkt_buff *pkt) { char src_ip[INET6_ADDRSTRLEN]; char dst_ip[INET6_ADDRSTRLEN]; struct ipv6hdr *ip = (struct ipv6hdr *) pkt_pull(pkt, sizeof(*ip)); if (ip == NULL) return; inet_ntop(AF_INET6, &ip->saddr, src_ip, sizeof(src_ip)); inet_ntop(AF_INET6, &ip->daddr, dst_ip, sizeof(dst_ip)); tprintf(" %s/%s Len %u", src_ip, dst_ip, ntohs(ip->payload_len)); pkt_set_proto(pkt, ð_lay3, ip->nexthdr); } struct protocol ipv6_ops = { .key = 0x86DD, .print_full = ipv6, .print_less = ipv6_less, }; ve'/>
context:
space:
mode:
authorEric W. Biederman <ebiederm@xmission.com>2017-01-03 14:18:43 +1300
committerEric W. Biederman <ebiederm@xmission.com>2017-01-10 13:34:43 +1300
commit3895dbf8985f656675b5bde610723a29cbce3fa7 (patch)
tree91d4517f09918fd573998eb40b8f35f08ed1c470
parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
mnt: Protect the mountpoint hashtable with mount_lock
Protecting the mountpoint hashtable with namespace_sem was sufficient until a call to umount_mnt was added to mntput_no_expire. At which point it became possible for multiple calls of put_mountpoint on the same hash chain to happen on the same time. Kristen Johansen <kjlx@templeofstupid.com> reported: > This can cause a panic when simultaneous callers of put_mountpoint > attempt to free the same mountpoint. This occurs because some callers > hold the mount_hash_lock, while others hold the namespace lock. Some > even hold both. > > In this submitter's case, the panic manifested itself as a GP fault in > put_mountpoint() when it called hlist_del() and attempted to dereference > a m_hash.pprev that had been poisioned by another thread. Al Viro observed that the simple fix is to switch from using the namespace_sem to the mount_lock to protect the mountpoint hash table. I have taken Al's suggested patch moved put_mountpoint in pivot_root (instead of taking mount_lock an additional time), and have replaced new_mountpoint with get_mountpoint a function that does the hash table lookup and addition under the mount_lock. The introduction of get_mounptoint ensures that only the mount_lock is needed to manipulate the mountpoint hashtable. d_set_mounted is modified to only set DCACHE_MOUNTED if it is not already set. This allows get_mountpoint to use the setting of DCACHE_MOUNTED to ensure adding a struct mountpoint for a dentry happens exactly once. Cc: stable@vger.kernel.org Fixes: ce07d891a089 ("mnt: Honor MNT_LOCKED when detaching mounts") Reported-by: Krister Johansen <kjlx@templeofstupid.com> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>