Revision e873e4b9cc7e8ce79e5c5627b32b107035bb3f5d authored by Wei Wang on 22 July 2018, 03:56:32 UTC, committed by David S. Miller on 23 July 2018, 18:19:02 UTC
In the code path where only rcu read lock is held, e.g. in the route lookup code path, it is not safe to directly call fib6_info_hold() because the fib6_info may already have been deleted but still exists in the rcu grace period. Holding reference to it could cause double free and crash the kernel. This patch adds a new function fib6_info_hold_safe() and replace fib6_info_hold() in all necessary places. Syzbot reported 3 crash traces because of this. One of them is: 8021q: adding VLAN 0 to HW filter on device team0 IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready dst_release: dst:(____ptrval____) refcnt:-1 dst_release: dst:(____ptrval____) refcnt:-2 WARNING: CPU: 1 PID: 4845 at include/net/dst.h:239 dst_hold include/net/dst.h:239 [inline] WARNING: CPU: 1 PID: 4845 at include/net/dst.h:239 ip6_setup_cork+0xd66/0x1830 net/ipv6/ip6_output.c:1204 dst_release: dst:(____ptrval____) refcnt:-1 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 4845 Comm: syz-executor493 Not tainted 4.18.0-rc3+ #10 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 panic+0x238/0x4e7 kernel/panic.c:184 dst_release: dst:(____ptrval____) refcnt:-2 dst_release: dst:(____ptrval____) refcnt:-3 __warn.cold.8+0x163/0x1ba kernel/panic.c:536 dst_release: dst:(____ptrval____) refcnt:-4 report_bug+0x252/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296 dst_release: dst:(____ptrval____) refcnt:-5 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992 RIP: 0010:dst_hold include/net/dst.h:239 [inline] RIP: 0010:ip6_setup_cork+0xd66/0x1830 net/ipv6/ip6_output.c:1204 Code: c1 ed 03 89 9d 18 ff ff ff 48 b8 00 00 00 00 00 fc ff df 41 c6 44 05 00 f8 e9 2d 01 00 00 4c 8b a5 c8 fe ff ff e8 1a f6 e6 fa <0f> 0b e9 6a fc ff ff e8 0e f6 e6 fa 48 8b 85 d0 fe ff ff 48 8d 78 RSP: 0018:ffff8801a8fcf178 EFLAGS: 00010293 RAX: ffff8801a8eba5c0 RBX: 0000000000000000 RCX: ffffffff869511e6 RDX: 0000000000000000 RSI: ffffffff869515b6 RDI: 0000000000000005 RBP: ffff8801a8fcf2c8 R08: ffff8801a8eba5c0 R09: ffffed0035ac8338 R10: ffffed0035ac8338 R11: ffff8801ad6419c3 R12: ffff8801a8fcf720 R13: ffff8801a8fcf6a0 R14: ffff8801ad6419c0 R15: ffff8801ad641980 ip6_make_skb+0x2c8/0x600 net/ipv6/ip6_output.c:1768 udpv6_sendmsg+0x2c90/0x35f0 net/ipv6/udp.c:1376 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:641 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:651 ___sys_sendmsg+0x51d/0x930 net/socket.c:2125 __sys_sendmmsg+0x240/0x6f0 net/socket.c:2220 __do_sys_sendmmsg net/socket.c:2249 [inline] __se_sys_sendmmsg net/socket.c:2246 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2246 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x446ba9 Code: e8 cc bb 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb39a469da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00000000006dcc54 RCX: 0000000000446ba9 RDX: 00000000000000b8 RSI: 0000000020001b00 RDI: 0000000000000003 RBP: 00000000006dcc50 R08: 00007fb39a46a700 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 45c828efc7a64843 R13: e6eeb815b9d8a477 R14: 5068caf6f713c6fc R15: 0000000000000001 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Reported-by: syzbot+902e2a1bcd4f7808cef5@syzkaller.appspotmail.com Reported-by: syzbot+8ae62d67f647abeeceb9@syzkaller.appspotmail.com Reported-by: syzbot+3f08feb14086930677d0@syzkaller.appspotmail.com Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 parent 5302a84
.clang-format
# SPDX-License-Identifier: GPL-2.0
#
# clang-format configuration file. Intended for clang-format >= 4.
#
# For more information, see:
#
# Documentation/process/clang-format.rst
# https://clang.llvm.org/docs/ClangFormat.html
# https://clang.llvm.org/docs/ClangFormatStyleOptions.html
#
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BinPackArguments: true
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# Taken from:
# git grep -h '^#define [^[:space:]]*for_each[^[:space:]]*(' include/ \
# | sed "s,^#define \([^[:space:]]*for_each[^[:space:]]*\)(.*$, - '\1'," \
# | sort | uniq
ForEachMacros:
- 'apei_estatus_for_each_section'
- 'ata_for_each_dev'
- 'ata_for_each_link'
- 'ax25_for_each'
- 'ax25_uid_for_each'
- 'bio_for_each_integrity_vec'
- '__bio_for_each_segment'
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- 'bip_for_each_vec'
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- 'blk_queue_for_each_rl'
- 'bond_for_each_slave'
- 'bond_for_each_slave_rcu'
- 'btree_for_each_safe128'
- 'btree_for_each_safe32'
- 'btree_for_each_safe64'
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- 'card_for_each_dev'
- 'cgroup_taskset_for_each'
- 'cgroup_taskset_for_each_leader'
- 'cpufreq_for_each_entry'
- 'cpufreq_for_each_entry_idx'
- 'cpufreq_for_each_valid_entry'
- 'cpufreq_for_each_valid_entry_idx'
- 'css_for_each_child'
- 'css_for_each_descendant_post'
- 'css_for_each_descendant_pre'
- 'device_for_each_child_node'
- 'drm_atomic_crtc_for_each_plane'
- 'drm_atomic_crtc_state_for_each_plane'
- 'drm_atomic_crtc_state_for_each_plane_state'
- 'drm_for_each_connector_iter'
- 'drm_for_each_crtc'
- 'drm_for_each_encoder'
- 'drm_for_each_encoder_mask'
- 'drm_for_each_fb'
- 'drm_for_each_legacy_plane'
- 'drm_for_each_plane'
- 'drm_for_each_plane_mask'
- 'drm_mm_for_each_hole'
- 'drm_mm_for_each_node'
- 'drm_mm_for_each_node_in_range'
- 'drm_mm_for_each_node_safe'
- 'for_each_active_drhd_unit'
- 'for_each_active_iommu'
- 'for_each_available_child_of_node'
- 'for_each_bio'
- 'for_each_board_func_rsrc'
- 'for_each_bvec'
- 'for_each_child_of_node'
- 'for_each_clear_bit'
- 'for_each_clear_bit_from'
- 'for_each_cmsghdr'
- 'for_each_compatible_node'
- 'for_each_console'
- 'for_each_cpu'
- 'for_each_cpu_and'
- 'for_each_cpu_not'
- 'for_each_cpu_wrap'
- 'for_each_dev_addr'
- 'for_each_dma_cap_mask'
- 'for_each_drhd_unit'
- 'for_each_dss_dev'
- 'for_each_efi_memory_desc'
- 'for_each_efi_memory_desc_in_map'
- 'for_each_endpoint_of_node'
- 'for_each_evictable_lru'
- 'for_each_fib6_node_rt_rcu'
- 'for_each_fib6_walker_rt'
- 'for_each_free_mem_range'
- 'for_each_free_mem_range_reverse'
- 'for_each_func_rsrc'
- 'for_each_hstate'
- 'for_each_if'
- 'for_each_iommu'
- 'for_each_ip_tunnel_rcu'
- 'for_each_irq_nr'
- 'for_each_lru'
- 'for_each_matching_node'
- 'for_each_matching_node_and_match'
- 'for_each_memblock'
- 'for_each_memblock_type'
- 'for_each_memcg_cache_index'
- 'for_each_mem_pfn_range'
- 'for_each_mem_range'
- 'for_each_mem_range_rev'
- 'for_each_migratetype_order'
- 'for_each_msi_entry'
- 'for_each_net'
- 'for_each_netdev'
- 'for_each_netdev_continue'
- 'for_each_netdev_continue_rcu'
- 'for_each_netdev_feature'
- 'for_each_netdev_in_bond_rcu'
- 'for_each_netdev_rcu'
- 'for_each_netdev_reverse'
- 'for_each_netdev_safe'
- 'for_each_net_rcu'
- 'for_each_new_connector_in_state'
- 'for_each_new_crtc_in_state'
- 'for_each_new_plane_in_state'
- 'for_each_new_private_obj_in_state'
- 'for_each_node'
- 'for_each_node_by_name'
- 'for_each_node_by_type'
- 'for_each_node_mask'
- 'for_each_node_state'
- 'for_each_node_with_cpus'
- 'for_each_node_with_property'
- 'for_each_of_allnodes'
- 'for_each_of_allnodes_from'
- 'for_each_of_pci_range'
- 'for_each_old_connector_in_state'
- 'for_each_old_crtc_in_state'
- 'for_each_oldnew_connector_in_state'
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- 'for_each_oldnew_private_obj_in_state'
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- 'for_each_old_private_obj_in_state'
- 'for_each_online_cpu'
- 'for_each_online_node'
- 'for_each_online_pgdat'
- 'for_each_pci_bridge'
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- 'for_each_pci_msi_entry'
- 'for_each_populated_zone'
- 'for_each_possible_cpu'
- 'for_each_present_cpu'
- 'for_each_prime_number'
- 'for_each_prime_number_from'
- 'for_each_process'
- 'for_each_process_thread'
- 'for_each_property_of_node'
- 'for_each_reserved_mem_region'
- 'for_each_resv_unavail_range'
- 'for_each_rtdcom'
- 'for_each_rtdcom_safe'
- 'for_each_set_bit'
- 'for_each_set_bit_from'
- 'for_each_sg'
- 'for_each_sg_page'
- '__for_each_thread'
- 'for_each_thread'
- 'for_each_zone'
- 'for_each_zone_zonelist'
- 'for_each_zone_zonelist_nodemask'
- 'fwnode_for_each_available_child_node'
- 'fwnode_for_each_child_node'
- 'fwnode_graph_for_each_endpoint'
- 'gadget_for_each_ep'
- 'hash_for_each'
- 'hash_for_each_possible'
- 'hash_for_each_possible_rcu'
- 'hash_for_each_possible_rcu_notrace'
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- 'hash_for_each_rcu'
- 'hash_for_each_safe'
- 'hctx_for_each_ctx'
- 'hlist_bl_for_each_entry'
- 'hlist_bl_for_each_entry_rcu'
- 'hlist_bl_for_each_entry_safe'
- 'hlist_for_each'
- 'hlist_for_each_entry'
- 'hlist_for_each_entry_continue'
- 'hlist_for_each_entry_continue_rcu'
- 'hlist_for_each_entry_continue_rcu_bh'
- 'hlist_for_each_entry_from'
- 'hlist_for_each_entry_from_rcu'
- 'hlist_for_each_entry_rcu'
- 'hlist_for_each_entry_rcu_bh'
- 'hlist_for_each_entry_rcu_notrace'
- 'hlist_for_each_entry_safe'
- '__hlist_for_each_rcu'
- 'hlist_for_each_safe'
- 'hlist_nulls_for_each_entry'
- 'hlist_nulls_for_each_entry_from'
- 'hlist_nulls_for_each_entry_rcu'
- 'hlist_nulls_for_each_entry_safe'
- 'ide_host_for_each_port'
- 'ide_port_for_each_dev'
- 'ide_port_for_each_present_dev'
- 'idr_for_each_entry'
- 'idr_for_each_entry_continue'
- 'idr_for_each_entry_ul'
- 'inet_bind_bucket_for_each'
- 'inet_lhash2_for_each_icsk_rcu'
- 'iov_for_each'
- 'key_for_each'
- 'key_for_each_safe'
- 'klp_for_each_func'
- 'klp_for_each_object'
- 'kvm_for_each_memslot'
- 'kvm_for_each_vcpu'
- 'list_for_each'
- 'list_for_each_entry'
- 'list_for_each_entry_continue'
- 'list_for_each_entry_continue_rcu'
- 'list_for_each_entry_continue_reverse'
- 'list_for_each_entry_from'
- 'list_for_each_entry_from_reverse'
- 'list_for_each_entry_lockless'
- 'list_for_each_entry_rcu'
- 'list_for_each_entry_reverse'
- 'list_for_each_entry_safe'
- 'list_for_each_entry_safe_continue'
- 'list_for_each_entry_safe_from'
- 'list_for_each_entry_safe_reverse'
- 'list_for_each_prev'
- 'list_for_each_prev_safe'
- 'list_for_each_safe'
- 'llist_for_each'
- 'llist_for_each_entry'
- 'llist_for_each_entry_safe'
- 'llist_for_each_safe'
- 'media_device_for_each_entity'
- 'media_device_for_each_intf'
- 'media_device_for_each_link'
- 'media_device_for_each_pad'
- 'netdev_for_each_lower_dev'
- 'netdev_for_each_lower_private'
- 'netdev_for_each_lower_private_rcu'
- 'netdev_for_each_mc_addr'
- 'netdev_for_each_uc_addr'
- 'netdev_for_each_upper_dev_rcu'
- 'netdev_hw_addr_list_for_each'
- 'nft_rule_for_each_expr'
- 'nla_for_each_attr'
- 'nla_for_each_nested'
- 'nlmsg_for_each_attr'
- 'nlmsg_for_each_msg'
- 'nr_neigh_for_each'
- 'nr_neigh_for_each_safe'
- 'nr_node_for_each'
- 'nr_node_for_each_safe'
- 'of_for_each_phandle'
- 'of_property_for_each_string'
- 'of_property_for_each_u32'
- 'pci_bus_for_each_resource'
- 'ping_portaddr_for_each_entry'
- 'plist_for_each'
- 'plist_for_each_continue'
- 'plist_for_each_entry'
- 'plist_for_each_entry_continue'
- 'plist_for_each_entry_safe'
- 'plist_for_each_safe'
- 'pnp_for_each_card'
- 'pnp_for_each_dev'
- 'protocol_for_each_card'
- 'protocol_for_each_dev'
- 'queue_for_each_hw_ctx'
- 'radix_tree_for_each_contig'
- 'radix_tree_for_each_slot'
- 'radix_tree_for_each_tagged'
- 'rbtree_postorder_for_each_entry_safe'
- 'resource_list_for_each_entry'
- 'resource_list_for_each_entry_safe'
- 'rhl_for_each_entry_rcu'
- 'rhl_for_each_rcu'
- 'rht_for_each'
- 'rht_for_each_continue'
- 'rht_for_each_entry'
- 'rht_for_each_entry_continue'
- 'rht_for_each_entry_rcu'
- 'rht_for_each_entry_rcu_continue'
- 'rht_for_each_entry_safe'
- 'rht_for_each_rcu'
- 'rht_for_each_rcu_continue'
- '__rq_for_each_bio'
- 'rq_for_each_segment'
- 'scsi_for_each_prot_sg'
- 'scsi_for_each_sg'
- 'sctp_for_each_hentry'
- 'sctp_skb_for_each'
- 'shdma_for_each_chan'
- '__shost_for_each_device'
- 'shost_for_each_device'
- 'sk_for_each'
- 'sk_for_each_bound'
- 'sk_for_each_entry_offset_rcu'
- 'sk_for_each_from'
- 'sk_for_each_rcu'
- 'sk_for_each_safe'
- 'sk_nulls_for_each'
- 'sk_nulls_for_each_from'
- 'sk_nulls_for_each_rcu'
- 'snd_pcm_group_for_each_entry'
- 'snd_soc_dapm_widget_for_each_path'
- 'snd_soc_dapm_widget_for_each_path_safe'
- 'snd_soc_dapm_widget_for_each_sink_path'
- 'snd_soc_dapm_widget_for_each_source_path'
- 'tb_property_for_each'
- 'udp_portaddr_for_each_entry'
- 'udp_portaddr_for_each_entry_rcu'
- 'usb_hub_for_each_child'
- 'v4l2_device_for_each_subdev'
- 'v4l2_m2m_for_each_dst_buf'
- 'v4l2_m2m_for_each_dst_buf_safe'
- 'v4l2_m2m_for_each_src_buf'
- 'v4l2_m2m_for_each_src_buf_safe'
- 'zorro_for_each_dev'
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Standard: Cpp03
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