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BUG: KMSAN: uninit-value in fib_rule_port_inrange include/net/fib_rules.h:162 [inline]
BUG: KMSAN: uninit-value in fib4_rule_match+0x6eb/0x740 net/ipv4/fib_rules.c:189
CPU: 0 PID: 10535 Comm: syz-executor4 Not tainted 4.17.0-rc5+ #103
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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
 __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686
 fib_rule_port_inrange include/net/fib_rules.h:162 [inline]
 fib4_rule_match+0x6eb/0x740 net/ipv4/fib_rules.c:189
 fib_rule_match net/core/fib_rules.c:273 [inline]
 fib_rules_lookup+0xb12/0xe70 net/core/fib_rules.c:288
 __fib_lookup+0x1bc/0x360 net/ipv4/fib_rules.c:93
 fib_lookup include/net/ip_fib.h:322 [inline]
 __fib_validate_source net/ipv4/fib_frontend.c:353 [inline]
 fib_validate_source+0xc23/0x1d50 net/ipv4/fib_frontend.c:434
 ip_mc_validate_source net/ipv4/route.c:1604 [inline]
 ip_route_input_mc net/ipv4/route.c:1622 [inline]
 ip_route_input_rcu+0xbeb/0x6280 net/ipv4/route.c:2146
 ip_route_input_noref+0x10e/0x140 net/ipv4/route.c:2098
 ip_rcv_finish+0x631/0x1d00 net/ipv4/ip_input.c:347
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0x118a/0x16d0 net/ipv4/ip_input.c:492
 __netif_receive_skb_core+0x47ff/0x4ac0 net/core/dev.c:4592
 __netif_receive_skb net/core/dev.c:4657 [inline]
 netif_receive_skb_internal+0x49d/0x630 net/core/dev.c:4731
 netif_receive_skb+0x230/0x240 net/core/dev.c:4755
 tun_rx_batched drivers/net/tun.c:1558 [inline]
 tun_get_user+0x6b61/0x7e90 drivers/net/tun.c:1962
 tun_chr_write_iter+0x1d4/0x330 drivers/net/tun.c:1990
 call_write_iter include/linux/fs.h:1784 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x7fb/0x9f0 fs/read_write.c:487
 vfs_write+0x467/0x8c0 fs/read_write.c:549
 ksys_write fs/read_write.c:598 [inline]
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x1bf/0x3e0 fs/read_write.c:607
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a09
RSP: 002b:00007f9c0e9d3c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9c0e9d46d4 RCX: 0000000000455a09
RDX: 000000000000fdef RSI: 0000000020000480 RDI: 0000000000000015
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000007bd R14: 0000000000700a58 R15: 0000000000000000

Local variable description: ----fl4.i@fib_validate_source
Variable was created at:
 fib_validate_source+0x127/0x1d50 net/ipv4/fib_frontend.c:410
 ip_mc_validate_source net/ipv4/route.c:1604 [inline]
 ip_route_input_mc net/ipv4/route.c:1622 [inline]
 ip_route_input_rcu+0xbeb/0x6280 net/ipv4/route.c:2146
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