From a88289f4ddee4165d5f796bd99e09eec3133c16b Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 14 Jan 2019 17:22:24 +0800 Subject: tipc: fix uninit-value in in tipc_conn_rcv_sub syzbot reported: BUG: KMSAN: uninit-value in tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373 CPU: 0 PID: 66 Comm: kworker/u4:4 Not tainted 4.17.0-rc3+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: tipc_rcv tipc_conn_recv_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:113 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373 tipc_conn_rcv_from_sock net/tipc/topsrv.c:409 [inline] tipc_conn_recv_work+0x3cd/0x560 net/tipc/topsrv.c:424 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2279 kthread+0x539/0x720 kernel/kthread.c:239 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:412 Local variable description: ----s.i@tipc_conn_recv_work Variable was created at: tipc_conn_recv_work+0x65/0x560 net/tipc/topsrv.c:419 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145 In tipc_conn_rcv_from_sock(), it always supposes the length of message received from sock_recvmsg() is not smaller than the size of struct tipc_subscr. However, this assumption is false. Especially when the length of received message is shorter than struct tipc_subscr size, we will end up touching uninitialized fields in tipc_conn_rcv_sub(). Reported-by: syzbot+8951a3065ee7fd6d6e23@syzkaller.appspotmail.com Reported-by: syzbot+75e6e042c5bbf691fc82@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/topsrv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/tipc') diff --git a/net/tipc/topsrv.c b/net/tipc/topsrv.c index efb16f69bd2c..a457c0fbbef1 100644 --- a/net/tipc/topsrv.c +++ b/net/tipc/topsrv.c @@ -398,7 +398,7 @@ static int tipc_conn_rcv_from_sock(struct tipc_conn *con) ret = sock_recvmsg(con->sock, &msg, MSG_DONTWAIT); if (ret == -EWOULDBLOCK) return -EWOULDBLOCK; - if (ret > 0) { + if (ret == sizeof(s)) { read_lock_bh(&sk->sk_callback_lock); ret = tipc_conn_rcv_sub(srv, con, &s); read_unlock_bh(&sk->sk_callback_lock); -- cgit v1.2.3-59-g8ed1b From 8b66fee7f8ee18f9c51260e7a43ab37db5177a05 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 14 Jan 2019 17:22:25 +0800 Subject: tipc: fix uninit-value in tipc_nl_compat_link_reset_stats syzbot reports following splat: BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:486 CPU: 1 PID: 11057 Comm: syz-executor0 Not tainted 4.20.0-rc7+ #2 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+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:295 strlen+0x3b/0xa0 lib/string.c:486 nla_put_string include/net/netlink.h:1154 [inline] tipc_nl_compat_link_reset_stats+0x1f0/0x360 net/tipc/netlink_compat.c:760 __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline] tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:344 tipc_nl_compat_handle net/tipc/netlink_compat.c:1107 [inline] tipc_nl_compat_recv+0x14d7/0x2760 net/tipc/netlink_compat.c:1210 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline] genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626 netlink_rcv_skb+0x444/0x640 net/netlink/af_netlink.c:2477 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0xf40/0x1020 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2557338c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f25573396d4 R13: 00000000004cb478 R14: 00000000004d86c8 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2759 [inline] __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x309/0xa20 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:998 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline] netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 The uninitialised access happened in tipc_nl_compat_link_reset_stats: nla_put_string(skb, TIPC_NLA_LINK_NAME, name) This is because name string is not validated before it's used. Reported-by: syzbot+e01d94b5a4c266be6e4c@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/netlink_compat.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'net/tipc') diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 77e4b2418f30..b2b115b22871 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -87,6 +87,11 @@ static int tipc_skb_tailroom(struct sk_buff *skb) return limit; } +static inline int TLV_GET_DATA_LEN(struct tlv_desc *tlv) +{ + return TLV_GET_LEN(tlv) - TLV_SPACE(0); +} + static int tipc_add_tlv(struct sk_buff *skb, u16 type, void *data, u16 len) { struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(skb); @@ -166,6 +171,11 @@ static struct sk_buff *tipc_get_err_tlv(char *str) return buf; } +static inline bool string_is_valid(char *s, int len) +{ + return memchr(s, '\0', len) ? true : false; +} + static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, struct tipc_nl_compat_msg *msg, struct sk_buff *arg) @@ -750,6 +760,7 @@ static int tipc_nl_compat_link_reset_stats(struct tipc_nl_compat_cmd_doit *cmd, { char *name; struct nlattr *link; + int len; name = (char *)TLV_DATA(msg->req); @@ -757,6 +768,10 @@ static int tipc_nl_compat_link_reset_stats(struct tipc_nl_compat_cmd_doit *cmd, if (!link) return -EMSGSIZE; + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME); + if (!string_is_valid(name, len)) + return -EINVAL; + if (nla_put_string(skb, TIPC_NLA_LINK_NAME, name)) return -EMSGSIZE; -- cgit v1.2.3-59-g8ed1b From 0762216c0ad2a2fccd63890648eca491f2c83d9a Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 14 Jan 2019 17:22:26 +0800 Subject: tipc: fix uninit-value in tipc_nl_compat_bearer_enable syzbot reported: BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:484 CPU: 1 PID: 6371 Comm: syz-executor652 Not tainted 4.19.0-rc8+ #70 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+0x306/0x460 lib/dump_stack.c:113 kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917 __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500 strlen+0x3b/0xa0 lib/string.c:484 nla_put_string include/net/netlink.h:1011 [inline] tipc_nl_compat_bearer_enable+0x238/0x7b0 net/tipc/netlink_compat.c:389 __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline] tipc_nl_compat_doit+0x39f/0xae0 net/tipc/netlink_compat.c:344 tipc_nl_compat_recv+0x147c/0x2760 net/tipc/netlink_compat.c:1107 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline] genl_rcv_msg+0x185c/0x1a20 net/netlink/genetlink.c:626 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2454 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x166d/0x1720 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x1391/0x1420 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x307/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x440179 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffef7beee8 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440179 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401a00 R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline] kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:180 kmsan_kmalloc+0xa4/0x120 mm/kmsan/kmsan_hooks.c:104 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:113 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2727 [inline] __kmalloc_node_track_caller+0xb43/0x1400 mm/slub.c:4360 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x422/0xe90 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:996 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline] netlink_sendmsg+0xcaf/0x1420 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x307/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 The root cause is that we don't validate whether bear name is a valid string in tipc_nl_compat_bearer_enable(). Meanwhile, we also fix the same issue in the following functions: tipc_nl_compat_bearer_disable() tipc_nl_compat_link_stat_dump() tipc_nl_compat_media_set() tipc_nl_compat_bearer_set() Reported-by: syzbot+b33d5cae0efd35dbfe77@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/netlink_compat.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'net/tipc') diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index b2b115b22871..68a0b7308936 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -389,6 +389,7 @@ static int tipc_nl_compat_bearer_enable(struct tipc_nl_compat_cmd_doit *cmd, struct nlattr *prop; struct nlattr *bearer; struct tipc_bearer_config *b; + int len; b = (struct tipc_bearer_config *)TLV_DATA(msg->req); @@ -396,6 +397,10 @@ static int tipc_nl_compat_bearer_enable(struct tipc_nl_compat_cmd_doit *cmd, if (!bearer) return -EMSGSIZE; + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME); + if (!string_is_valid(b->name, len)) + return -EINVAL; + if (nla_put_string(skb, TIPC_NLA_BEARER_NAME, b->name)) return -EMSGSIZE; @@ -421,6 +426,7 @@ static int tipc_nl_compat_bearer_disable(struct tipc_nl_compat_cmd_doit *cmd, { char *name; struct nlattr *bearer; + int len; name = (char *)TLV_DATA(msg->req); @@ -428,6 +434,10 @@ static int tipc_nl_compat_bearer_disable(struct tipc_nl_compat_cmd_doit *cmd, if (!bearer) return -EMSGSIZE; + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME); + if (!string_is_valid(name, len)) + return -EINVAL; + if (nla_put_string(skb, TIPC_NLA_BEARER_NAME, name)) return -EMSGSIZE; @@ -488,6 +498,7 @@ static int tipc_nl_compat_link_stat_dump(struct tipc_nl_compat_msg *msg, struct nlattr *prop[TIPC_NLA_PROP_MAX + 1]; struct nlattr *stats[TIPC_NLA_STATS_MAX + 1]; int err; + int len; if (!attrs[TIPC_NLA_LINK]) return -EINVAL; @@ -514,6 +525,11 @@ static int tipc_nl_compat_link_stat_dump(struct tipc_nl_compat_msg *msg, return err; name = (char *)TLV_DATA(msg->req); + + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME); + if (!string_is_valid(name, len)) + return -EINVAL; + if (strcmp(name, nla_data(link[TIPC_NLA_LINK_NAME])) != 0) return 0; @@ -654,6 +670,7 @@ static int tipc_nl_compat_media_set(struct sk_buff *skb, struct nlattr *prop; struct nlattr *media; struct tipc_link_config *lc; + int len; lc = (struct tipc_link_config *)TLV_DATA(msg->req); @@ -661,6 +678,10 @@ static int tipc_nl_compat_media_set(struct sk_buff *skb, if (!media) return -EMSGSIZE; + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_MEDIA_NAME); + if (!string_is_valid(lc->name, len)) + return -EINVAL; + if (nla_put_string(skb, TIPC_NLA_MEDIA_NAME, lc->name)) return -EMSGSIZE; @@ -681,6 +702,7 @@ static int tipc_nl_compat_bearer_set(struct sk_buff *skb, struct nlattr *prop; struct nlattr *bearer; struct tipc_link_config *lc; + int len; lc = (struct tipc_link_config *)TLV_DATA(msg->req); @@ -688,6 +710,10 @@ static int tipc_nl_compat_bearer_set(struct sk_buff *skb, if (!bearer) return -EMSGSIZE; + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_MEDIA_NAME); + if (!string_is_valid(lc->name, len)) + return -EINVAL; + if (nla_put_string(skb, TIPC_NLA_BEARER_NAME, lc->name)) return -EMSGSIZE; -- cgit v1.2.3-59-g8ed1b From edf5ff04a45750ac8ce2435974f001dc9cfbf055 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 14 Jan 2019 17:22:27 +0800 Subject: tipc: fix uninit-value in tipc_nl_compat_link_set syzbot reports following splat: BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:486 CPU: 1 PID: 9306 Comm: syz-executor172 Not tainted 4.20.0-rc7+ #2 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+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 strlen+0x3b/0xa0 lib/string.c:486 nla_put_string include/net/netlink.h:1154 [inline] __tipc_nl_compat_link_set net/tipc/netlink_compat.c:708 [inline] tipc_nl_compat_link_set+0x929/0x1220 net/tipc/netlink_compat.c:744 __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline] tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:344 tipc_nl_compat_handle net/tipc/netlink_compat.c:1107 [inline] tipc_nl_compat_recv+0x14d7/0x2760 net/tipc/netlink_compat.c:1210 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline] genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626 netlink_rcv_skb+0x444/0x640 net/netlink/af_netlink.c:2477 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0xf40/0x1020 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 The uninitialised access happened in nla_put_string(skb, TIPC_NLA_LINK_NAME, lc->name) This is because lc->name string is not validated before it's used. Reported-by: syzbot+d78b8a29241a195aefb8@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/netlink_compat.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/tipc') diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 68a0b7308936..89e6ae3b3c33 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -762,9 +762,14 @@ static int tipc_nl_compat_link_set(struct tipc_nl_compat_cmd_doit *cmd, struct tipc_link_config *lc; struct tipc_bearer *bearer; struct tipc_media *media; + int len; lc = (struct tipc_link_config *)TLV_DATA(msg->req); + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME); + if (!string_is_valid(lc->name, len)) + return -EINVAL; + media = tipc_media_find(lc->name); if (media) { cmd->doit = &__tipc_nl_media_set; -- cgit v1.2.3-59-g8ed1b From 974cb0e3e7c963ced06c4e32c5b2884173fa5e01 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 14 Jan 2019 17:22:28 +0800 Subject: tipc: fix uninit-value in tipc_nl_compat_name_table_dump syzbot reported: BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline] BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:59 [inline] BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x4a8/0xba0 net/tipc/netlink_compat.c:826 CPU: 0 PID: 6290 Comm: syz-executor848 Not tainted 4.19.0-rc8+ #70 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+0x306/0x460 lib/dump_stack.c:113 kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917 __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline] __fswab32 include/uapi/linux/swab.h:59 [inline] tipc_nl_compat_name_table_dump+0x4a8/0xba0 net/tipc/netlink_compat.c:826 __tipc_nl_compat_dumpit+0x59e/0xdb0 net/tipc/netlink_compat.c:205 tipc_nl_compat_dumpit+0x63a/0x820 net/tipc/netlink_compat.c:270 tipc_nl_compat_handle net/tipc/netlink_compat.c:1151 [inline] tipc_nl_compat_recv+0x1402/0x2760 net/tipc/netlink_compat.c:1210 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline] genl_rcv_msg+0x185c/0x1a20 net/netlink/genetlink.c:626 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2454 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x166d/0x1720 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x1391/0x1420 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x307/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x440179 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffecec49318 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440179 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401a00 R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline] kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:180 kmsan_kmalloc+0xa4/0x120 mm/kmsan/kmsan_hooks.c:104 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:113 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2727 [inline] __kmalloc_node_track_caller+0xb43/0x1400 mm/slub.c:4360 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x422/0xe90 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:996 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline] netlink_sendmsg+0xcaf/0x1420 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x307/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 We cannot take for granted the thing that the length of data contained in TLV is longer than the size of struct tipc_name_table_query in tipc_nl_compat_name_table_dump(). Reported-by: syzbot+06e771a754829716a327@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/netlink_compat.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/tipc') diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 89e6ae3b3c33..b90786ca1d21 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -824,6 +824,8 @@ static int tipc_nl_compat_name_table_dump_header(struct tipc_nl_compat_msg *msg) }; ntq = (struct tipc_name_table_query *)TLV_DATA(msg->req); + if (TLV_GET_DATA_LEN(msg->req) < sizeof(struct tipc_name_table_query)) + return -EINVAL; depth = ntohl(ntq->depth); -- cgit v1.2.3-59-g8ed1b From 2753ca5d9009c180dbfd4c802c80983b4b6108d1 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 14 Jan 2019 17:22:29 +0800 Subject: tipc: fix uninit-value in tipc_nl_compat_doit BUG: KMSAN: uninit-value in tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335 CPU: 0 PID: 4514 Comm: syz-executor485 Not tainted 4.16.0+ #87 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335 tipc_nl_compat_recv+0x164b/0x2700 net/tipc/netlink_compat.c:1153 genl_family_rcv_msg net/netlink/genetlink.c:599 [inline] genl_rcv_msg+0x1686/0x1810 net/netlink/genetlink.c:624 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2447 genl_rcv+0x63/0x80 net/netlink/genetlink.c:635 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x166b/0x1740 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x43fda9 RSP: 002b:00007ffd0c184ba8 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9 RDX: 0000000000000000 RSI: 0000000020023000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000213 R12: 00000000004016d0 R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline] netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 In tipc_nl_compat_recv(), when the len variable returned by nlmsg_attrlen() is 0, the message is still treated as a valid one, which is obviously unresonable. When len is zero, it means the message not only doesn't contain any valid TLV payload, but also TLV header is not included. Under this stituation, tlv_type field in TLV header is still accessed in tipc_nl_compat_dumpit() or tipc_nl_compat_doit(), but the field space is obviously illegal. Of course, it is not initialized. Reported-by: syzbot+bca0dc46634781f08b38@syzkaller.appspotmail.com Reported-by: syzbot+6bdb590321a7ae40c1a6@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/netlink_compat.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/tipc') diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index b90786ca1d21..4ad3586da8f0 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -1256,7 +1256,7 @@ static int tipc_nl_compat_recv(struct sk_buff *skb, struct genl_info *info) } len = nlmsg_attrlen(req_nlh, GENL_HDRLEN + TIPC_GENL_HDRLEN); - if (len && !TLV_OK(msg.req, len)) { + if (!len || !TLV_OK(msg.req, len)) { msg.rep = tipc_get_err_tlv(TIPC_CFG_NOT_SUPPORTED); err = -EOPNOTSUPP; goto send; -- cgit v1.2.3-59-g8ed1b