================================================================== BUG: KCSAN: data-race in data_alloc / prb_reserve write to 0xffffffff86673c38 of 8 bytes by task 12326 on cpu 0: data_alloc+0x291/0x2c0 kernel/printk/printk_ringbuffer.c:1096 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86 _printk+0x7a/0xa0 kernel/printk/printk.c:2457 __ext4_msg+0x18e/0x1a0 fs/ext4/super.c:998 mpage_map_and_submit_extent fs/ext4/inode.c:2289 [inline] ext4_do_writepages+0x19ca/0x2130 fs/ext4/inode.c:2735 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2824 do_writepages+0x1d8/0x480 mm/page-writeback.c:2702 __writeback_single_inode+0x89/0x850 fs/fs-writeback.c:1680 writeback_sb_inodes+0x461/0xa30 fs/fs-writeback.c:1976 wb_writeback+0x262/0x640 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x1a8/0x940 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 read to 0xffffffff86673c38 of 8 bytes by task 14729 on cpu 1: desc_read kernel/printk/printk_ringbuffer.c:482 [inline] desc_push_tail kernel/printk/printk_ringbuffer.c:778 [inline] desc_reserve kernel/printk/printk_ringbuffer.c:924 [inline] prb_reserve+0x235/0xb60 kernel/printk/printk_ringbuffer.c:1619 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86 _printk+0x7a/0xa0 kernel/printk/printk.c:2457 fail_dump lib/fault-inject.c:46 [inline] should_fail_ex+0x20b/0x230 lib/fault-inject.c:154 should_failslab+0x8f/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4072 [inline] slab_alloc_node mm/slub.c:4148 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_noprof+0xab/0x3f0 mm/slub.c:4310 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] ethnl_default_start+0x8c/0x330 net/ethtool/netlink.c:616 genl_start+0x2e8/0x3a0 net/netlink/genetlink.c:1005 __netlink_dump_start+0x32a/0x520 net/netlink/af_netlink.c:2423 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:1076 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline] genl_rcv_msg+0x4e5/0x6c0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2542 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x599/0x670 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x5cc/0x6e0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x140/0x180 net/socket.c:726 ____sys_sendmsg+0x312/0x410 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x19d/0x230 net/socket.c:2669 __do_sys_sendmsg net/socket.c:2674 [inline] __se_sys_sendmsg net/socket.c:2672 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2672 x64_sys_call+0x2734/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0xfffffffffffefb48 -> 0x0000000000095bb8 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 14729 Comm: syz.3.3295 Not tainted 6.13.0-rc2-syzkaller-00292-ga446e965a188 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 ================================================================== FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 UID: 0 PID: 14729 Comm: syz.3.3295 Not tainted 6.13.0-rc2-syzkaller-00292-ga446e965a188 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xf2/0x150 lib/dump_stack.c:120 dump_stack+0x15/0x1a lib/dump_stack.c:129 fail_dump lib/fault-inject.c:53 [inline] should_fail_ex+0x223/0x230 lib/fault-inject.c:154 should_failslab+0x8f/0xb0 mm/failslab.c:46 slab_pre_alloc_hook mm/slub.c:4072 [inline] slab_alloc_node mm/slub.c:4148 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_noprof+0xab/0x3f0 mm/slub.c:4310 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] ethnl_default_start+0x8c/0x330 net/ethtool/netlink.c:616 genl_start+0x2e8/0x3a0 net/netlink/genetlink.c:1005 __netlink_dump_start+0x32a/0x520 net/netlink/af_netlink.c:2423 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:1076 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline] genl_rcv_msg+0x4e5/0x6c0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2542 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x599/0x670 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x5cc/0x6e0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x140/0x180 net/socket.c:726 ____sys_sendmsg+0x312/0x410 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x19d/0x230 net/socket.c:2669 __do_sys_sendmsg net/socket.c:2674 [inline] __se_sys_sendmsg net/socket.c:2672 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2672 x64_sys_call+0x2734/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7a54335d19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7a529a1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f7a54525fa0 RCX: 00007f7a54335d19 RDX: 0000000000000000 RSI: 0000000020001ac0 RDI: 0000000000000005 RBP: 00007f7a529a1090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f7a54525fa0 R15: 00007ffd93b1e688