================================================================== BUG: KCSAN: data-race in data_push_tail / mac_address_string write to 0xffffffff883e40b0 of 1 bytes by task 11812 on cpu 0: string_nocheck lib/vsprintf.c:650 [inline] mac_address_string+0x55d/0x5e0 lib/vsprintf.c:1306 pointer+0x75a/0xd20 lib/vsprintf.c:2439 vsnprintf+0x861/0xe30 lib/vsprintf.c:2828 vscnprintf+0x42/0x90 lib/vsprintf.c:2930 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2165 vprintk_store+0x570/0x810 kernel/printk/printk.c:2279 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2329 vprintk_default+0x26/0x30 kernel/printk/printk.c:2363 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2373 batadv_check_known_mac_addr+0x147/0x180 net/batman-adv/hard-interface.c:526 batadv_hard_if_event+0x4b0/0x1000 net/batman-adv/hard-interface.c:998 notifier_call_chain kernel/notifier.c:93 [inline] raw_notifier_call_chain+0x6f/0x1d0 kernel/notifier.c:461 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:1950 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline] call_netdevice_notifiers net/core/dev.c:2002 [inline] dev_set_mac_address+0x1ff/0x260 net/core/dev.c:8955 dev_set_mac_address_user+0x31/0x50 net/core/dev.c:8969 do_setlink+0x510/0x2480 net/core/rtnetlink.c:2839 __rtnl_newlink net/core/rtnetlink.c:3680 [inline] rtnl_newlink+0x11a1/0x1690 net/core/rtnetlink.c:3727 rtnetlink_rcv_msg+0x82e/0x8e0 net/core/rtnetlink.c:6595 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2559 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6613 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x58d/0x660 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x5d3/0x6e0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x140/0x180 net/socket.c:745 __sys_sendto+0x1e5/0x260 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x78/0x90 net/socket.c:2199 x64_sys_call+0x16bb/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff883e40b0 of 8 bytes by task 11997 on cpu 1: data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline] data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1054 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2269 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2329 vprintk_default+0x26/0x30 kernel/printk/printk.c:2363 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2373 fail_dump lib/fault-inject.c:45 [inline] should_fail_ex+0x211/0x230 lib/fault-inject.c:153 __should_fail_alloc_page+0xfd/0x110 mm/fail_page_alloc.c:42 prepare_alloc_pages mm/page_alloc.c:4348 [inline] __alloc_pages+0x109/0x360 mm/page_alloc.c:4564 alloc_pages_mpol+0xb1/0x1e0 mm/mempolicy.c:2264 alloc_pages mm/mempolicy.c:2335 [inline] folio_alloc+0xe8/0x100 mm/mempolicy.c:2342 filemap_alloc_folio+0x69/0x220 mm/filemap.c:984 __filemap_get_folio+0x298/0x5b0 mm/filemap.c:1926 pagecache_get_page+0x2a/0xa0 mm/folio-compat.c:93 grab_cache_page_write_begin+0x2e/0x40 mm/folio-compat.c:103 block_write_begin+0x31/0x170 fs/buffer.c:2209 cont_write_begin+0x486/0x6b0 fs/buffer.c:2567 fat_write_begin+0x61/0xf0 fs/fat/inode.c:230 generic_perform_write+0x1d5/0x410 mm/filemap.c:3974 __generic_file_write_iter+0xec/0x120 mm/filemap.c:4066 generic_file_write_iter+0x7d/0x1d0 mm/filemap.c:4095 do_iter_readv_writev+0x339/0x3e0 vfs_writev+0x2e9/0x860 fs/read_write.c:971 do_pwritev fs/read_write.c:1072 [inline] __do_sys_pwritev2 fs/read_write.c:1131 [inline] __se_sys_pwritev2+0x10c/0x1d0 fs/read_write.c:1122 __x64_sys_pwritev2+0x78/0x90 fs/read_write.c:1122 x64_sys_call+0xf52/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:329 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000fffff6ae -> 0x3a61613a61613a61 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 11997 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 ================================================================== CPU: 1 PID: 11997 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xf2/0x150 lib/dump_stack.c:114 dump_stack+0x15/0x20 lib/dump_stack.c:123 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x229/0x230 lib/fault-inject.c:153 __should_fail_alloc_page+0xfd/0x110 mm/fail_page_alloc.c:42 prepare_alloc_pages mm/page_alloc.c:4348 [inline] __alloc_pages+0x109/0x360 mm/page_alloc.c:4564 alloc_pages_mpol+0xb1/0x1e0 mm/mempolicy.c:2264 alloc_pages mm/mempolicy.c:2335 [inline] folio_alloc+0xe8/0x100 mm/mempolicy.c:2342 filemap_alloc_folio+0x69/0x220 mm/filemap.c:984 __filemap_get_folio+0x298/0x5b0 mm/filemap.c:1926 pagecache_get_page+0x2a/0xa0 mm/folio-compat.c:93 grab_cache_page_write_begin+0x2e/0x40 mm/folio-compat.c:103 block_write_begin+0x31/0x170 fs/buffer.c:2209 cont_write_begin+0x486/0x6b0 fs/buffer.c:2567 fat_write_begin+0x61/0xf0 fs/fat/inode.c:230 generic_perform_write+0x1d5/0x410 mm/filemap.c:3974 __generic_file_write_iter+0xec/0x120 mm/filemap.c:4066 generic_file_write_iter+0x7d/0x1d0 mm/filemap.c:4095 do_iter_readv_writev+0x339/0x3e0 vfs_writev+0x2e9/0x860 fs/read_write.c:971 do_pwritev fs/read_write.c:1072 [inline] __do_sys_pwritev2 fs/read_write.c:1131 [inline] __se_sys_pwritev2+0x10c/0x1d0 fs/read_write.c:1122 __x64_sys_pwritev2+0x78/0x90 fs/read_write.c:1122 x64_sys_call+0xf52/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:329 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcec865bea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcec79b40c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007fcec878a050 RCX: 00007fcec865bea9 RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000005 RBP: 00007fcec79b4120 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000007a00 R11: 0000000000000246 R12: 0000000000000001 R13: 000000000000006e R14: 00007fcec878a050 R15: 00007ffc1bb74058