Hello, syzbot found the following issue on: HEAD commit: ee9407ea37bf kmsan: core: massage include/linux/sched.h git tree: https://github.com/google/kmsan.git master console output: https://syzkaller.appspot.com/x/log.txt?x=1656babe300000 kernel config: https://syzkaller.appspot.com/x/.config?x=92983a87b2ce6cdb dashboard link: https://syzkaller.appspot.com/bug?extid=6d38e380afc486ec44a1 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6d38e380afc486ec44a1@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in crc_ccitt_byte include/linux/crc-ccitt.h:15 [inline] BUG: KMSAN: uninit-value in crc_ccitt+0x364/0x3f0 lib/crc-ccitt.c:102 CPU: 1 PID: 9742 Comm: syz-executor.4 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x24c/0x2e0 lib/dump_stack.c:120 kmsan_report+0xfb/0x1e0 mm/kmsan/report.c:121 __msan_warning+0xd7/0x160 mm/kmsan/instrumentation.c:201 crc_ccitt_byte include/linux/crc-ccitt.h:15 [inline] crc_ccitt+0x364/0x3f0 lib/crc-ccitt.c:102 ieee802154_tx+0x300/0x800 net/mac802154/tx.c:72 ieee802154_subif_start_xmit+0x16a/0x250 net/mac802154/tx.c:132 __netdev_start_xmit include/linux/netdevice.h:4944 [inline] netdev_start_xmit include/linux/netdevice.h:4958 [inline] xmit_one+0x2b6/0x760 net/core/dev.c:3654 dev_hard_start_xmit+0x196/0x420 net/core/dev.c:3670 sch_direct_xmit+0x554/0x1b90 net/sched/sch_generic.c:336 qdisc_restart net/sched/sch_generic.c:401 [inline] __qdisc_run+0x35b/0x490 net/sched/sch_generic.c:409 qdisc_run include/net/pkt_sched.h:131 [inline] __dev_xmit_skb net/core/dev.c:3857 [inline] __dev_queue_xmit+0x1e3f/0x5440 net/core/dev.c:4214 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4279 dgram_sendmsg+0x1142/0x15d0 net/ieee802154/socket.c:682 ieee802154_sock_sendmsg+0xec/0x130 net/ieee802154/socket.c:97 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2337 ___sys_sendmsg net/socket.c:2391 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2420 __compat_sys_sendmsg net/compat.c:347 [inline] __do_compat_sys_sendmsg net/compat.c:354 [inline] __se_compat_sys_sendmsg net/compat.c:351 [inline] __ia32_compat_sys_sendmsg+0xed/0x130 net/compat.c:351 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline] __do_fast_syscall_32+0x132/0x1b0 arch/x86/entry/common.c:149 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:179 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:222 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fa3549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f559d5fc EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000020000880 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/core.c:106 [inline] kmsan_internal_chain_origin+0xab/0x120 mm/kmsan/core.c:244 kmsan_memmove_metadata+0x23b/0x2c0 mm/kmsan/core.c:192 __msan_memcpy+0x5e/0x90 mm/kmsan/instrumentation.c:111 ieee802154_hdr_push+0xcd7/0xdd0 net/ieee802154/header_ops.c:117 ieee802154_header_create+0xd07/0x1070 net/mac802154/iface.c:404 wpan_dev_hard_header include/net/cfg802154.h:374 [inline] dgram_sendmsg+0xf4b/0x15d0 net/ieee802154/socket.c:670 ieee802154_sock_sendmsg+0xec/0x130 net/ieee802154/socket.c:97 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2337 ___sys_sendmsg net/socket.c:2391 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2420 __compat_sys_sendmsg net/compat.c:347 [inline] __do_compat_sys_sendmsg net/compat.c:354 [inline] __se_compat_sys_sendmsg net/compat.c:351 [inline] __ia32_compat_sys_sendmsg+0xed/0x130 net/compat.c:351 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline] __do_fast_syscall_32+0x132/0x1b0 arch/x86/entry/common.c:149 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:179 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:222 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/core.c:106 [inline] kmsan_internal_chain_origin+0xab/0x120 mm/kmsan/core.c:244 kmsan_memmove_metadata+0x23b/0x2c0 mm/kmsan/core.c:192 __msan_memcpy+0x5e/0x90 mm/kmsan/instrumentation.c:111 ieee802154_hdr_push_addr net/ieee802154/header_ops.c:35 [inline] ieee802154_hdr_push+0x2b0/0xdd0 net/ieee802154/header_ops.c:89 ieee802154_header_create+0xd07/0x1070 net/mac802154/iface.c:404 wpan_dev_hard_header include/net/cfg802154.h:374 [inline] dgram_sendmsg+0xf4b/0x15d0 net/ieee802154/socket.c:670 ieee802154_sock_sendmsg+0xec/0x130 net/ieee802154/socket.c:97 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2337 ___sys_sendmsg net/socket.c:2391 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2420 __compat_sys_sendmsg net/compat.c:347 [inline] __do_compat_sys_sendmsg net/compat.c:354 [inline] __se_compat_sys_sendmsg net/compat.c:351 [inline] __ia32_compat_sys_sendmsg+0xed/0x130 net/compat.c:351 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline] __do_fast_syscall_32+0x132/0x1b0 arch/x86/entry/common.c:149 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:179 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:222 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/core.c:106 [inline] kmsan_internal_chain_origin+0xab/0x120 mm/kmsan/core.c:244 kmsan_memmove_metadata+0x23b/0x2c0 mm/kmsan/core.c:192 __msan_memcpy+0x5e/0x90 mm/kmsan/instrumentation.c:111 ieee802154_header_create+0xcd1/0x1070 net/mac802154/iface.c:402 wpan_dev_hard_header include/net/cfg802154.h:374 [inline] dgram_sendmsg+0xf4b/0x15d0 net/ieee802154/socket.c:670 ieee802154_sock_sendmsg+0xec/0x130 net/ieee802154/socket.c:97 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2337 ___sys_sendmsg net/socket.c:2391 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2420 __compat_sys_sendmsg net/compat.c:347 [inline] __do_compat_sys_sendmsg net/compat.c:354 [inline] __se_compat_sys_sendmsg net/compat.c:351 [inline] __ia32_compat_sys_sendmsg+0xed/0x130 net/compat.c:351 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline] __do_fast_syscall_32+0x132/0x1b0 arch/x86/entry/common.c:149 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:179 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:222 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Local variable ----dst_addr@dgram_sendmsg created at: dgram_sendmsg+0x8a/0x15d0 net/ieee802154/socket.c:607 dgram_sendmsg+0x8a/0x15d0 net/ieee802154/socket.c:607 ===================================================== --- This report is generated by a bot. 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