linux/net/tipc
Shigeru Yoshida 19b3f72a41 tipc: Change nla_policy for bearer-related names to NLA_NUL_STRING
syzbot reported the following uninit-value access issue [1]:

=====================================================
BUG: KMSAN: uninit-value in strlen lib/string.c:418 [inline]
BUG: KMSAN: uninit-value in strstr+0xb8/0x2f0 lib/string.c:756
 strlen lib/string.c:418 [inline]
 strstr+0xb8/0x2f0 lib/string.c:756
 tipc_nl_node_reset_link_stats+0x3ea/0xb50 net/tipc/node.c:2595
 genl_family_rcv_msg_doit net/netlink/genetlink.c:971 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline]
 genl_rcv_msg+0x11ec/0x1290 net/netlink/genetlink.c:1066
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2545
 genl_rcv+0x40/0x60 net/netlink/genetlink.c:1075
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0xf47/0x1250 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg net/socket.c:753 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2541
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2595
 __sys_sendmsg net/socket.c:2624 [inline]
 __do_sys_sendmsg net/socket.c:2633 [inline]
 __se_sys_sendmsg net/socket.c:2631 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:559
 __alloc_skb+0x318/0x740 net/core/skbuff.c:650
 alloc_skb include/linux/skbuff.h:1286 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1214 [inline]
 netlink_sendmsg+0xb34/0x13d0 net/netlink/af_netlink.c:1885
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg net/socket.c:753 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2541
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2595
 __sys_sendmsg net/socket.c:2624 [inline]
 __do_sys_sendmsg net/socket.c:2633 [inline]
 __se_sys_sendmsg net/socket.c:2631 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

TIPC bearer-related names including link names must be null-terminated
strings. If a link name which is not null-terminated is passed through
netlink, strstr() and similar functions can cause buffer overrun. This
causes the above issue.

This patch changes the nla_policy for bearer-related names from NLA_STRING
to NLA_NUL_STRING. This resolves the issue by ensuring that only
null-terminated strings are accepted as bearer-related names.

syzbot reported similar uninit-value issue related to bearer names [2]. The
root cause of this issue is that a non-null-terminated bearer name was
passed. This patch also resolved this issue.

Fixes: 7be57fc691 ("tipc: add link get/dump to new netlink api")
Fixes: 0655f6a863 ("tipc: add bearer disable/enable to new netlink api")
Reported-and-tested-by: syzbot+5138ca807af9d2b42574@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=5138ca807af9d2b42574 [1]
Reported-and-tested-by: syzbot+9425c47dccbcb4c17d51@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9425c47dccbcb4c17d51 [2]
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231030075540.3784537-1-syoshida@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-01 22:26:37 -07:00
..
addr.c tipc: introduce new unified address type for internal use 2021-03-17 11:51:04 -07:00
addr.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
bcast.c net: tipc: fix FB_MTU eat two pages 2021-06-28 13:31:57 -07:00
bcast.h
bearer.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-06-15 22:19:41 -07:00
bearer.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
core.c tipc: fix use-after-free Read in tipc_named_reinit 2022-06-17 11:39:10 +01:00
core.h minmax: add in_range() macro 2023-08-24 16:20:18 -07:00
crypto.c tipc: fix a potential deadlock on &tx->lock 2023-10-04 13:24:12 -07:00
crypto.h net/tipc: fix tipc header files for kernel-doc 2020-12-01 15:37:41 -08:00
diag.c
discover.c treewide: Convert del_timer*() to timer_shutdown*() 2022-12-25 13:38:09 -08:00
discover.h
eth_media.c tipc: constify dev_addr passing 2021-10-13 09:40:46 -07:00
group.c tipc: update address terminology in code 2020-11-27 17:34:01 -08:00
group.h tipc: update address terminology in code 2020-11-27 17:34:01 -08:00
ib_media.c tipc: constify dev_addr passing 2021-10-13 09:40:46 -07:00
Kconfig
link.c tipc: Use size_add() in calls to struct_size() 2023-09-18 09:38:32 +01:00
link.h tipc: Remove unused declaration tipc_link_build_bc_sync_msg() 2023-08-09 13:03:14 -07:00
Makefile
monitor.c treewide: Convert del_timer*() to timer_shutdown*() 2022-12-25 13:38:09 -08:00
monitor.h
msg.c net: tipc: replace align() with ALIGN in msg.c 2021-06-28 13:31:57 -07:00
msg.h net: tipc: remove unused static inlines 2022-01-27 13:53:27 +00:00
name_distr.c net/tipc: Remove unused struct distr_queue_item 2022-09-29 18:48:32 -07:00
name_distr.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
name_table.c tipc: cleanup unused function 2022-06-17 11:43:57 +01:00
name_table.h tipc: cleanup unused function 2022-06-17 11:43:57 +01:00
net.c tipc: simplify the finalize work queue 2021-05-18 13:22:09 -07:00
net.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
netlink_compat.c genetlink: use attrs from struct genl_info 2023-08-15 15:00:45 -07:00
netlink.c tipc: Change nla_policy for bearer-related names to NLA_NUL_STRING 2023-11-01 22:26:37 -07:00
netlink.h
node.c genetlink: use attrs from struct genl_info 2023-08-15 15:00:45 -07:00
node.h
socket.c genetlink: use attrs from struct genl_info 2023-08-15 15:00:45 -07:00
socket.h
subscr.c tipc:subscr.c: fix a spelling mistake 2021-06-10 13:48:43 -07:00
subscr.h tipc: fix htmldoc and smatch warnings 2021-03-29 16:28:50 -07:00
sysctl.c
topsrv.c net/sock: Introduce trace_sk_data_ready() 2023-01-23 11:26:50 +00:00
topsrv.h
trace.c net/tipc: fix various kernel-doc warnings 2020-12-01 15:37:46 -08:00
trace.h
udp_media.c genetlink: use attrs from struct genl_info 2023-08-15 15:00:45 -07:00
udp_media.h