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KMSAN: uninit-value in sixpack_receive_buf (3)

Status: closed as invalid on 2025/07/30 20:31
Subsystems: hams
[Documentation on labels]
First crash: 45d, last: 45d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in sixpack_receive_buf hams 7 1 261d 257d 0/29 auto-obsoleted due to no activity on 2025/03/01 01:58
upstream KMSAN: uninit-value in sixpack_receive_buf (2) hams 7 1 145d 145d 0/29 closed as invalid on 2025/04/18 16:40

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in sixpack_decode drivers/net/hamradio/6pack.c:938 [inline]
BUG: KMSAN: uninit-value in sixpack_receive_buf+0x6eb/0x2ef0 drivers/net/hamradio/6pack.c:447
 sixpack_decode drivers/net/hamradio/6pack.c:938 [inline]
 sixpack_receive_buf+0x6eb/0x2ef0 drivers/net/hamradio/6pack.c:447
 tty_ldisc_receive_buf+0x1f4/0x2c0 drivers/tty/tty_buffer.c:391
 tty_port_default_receive_buf+0xd7/0x1a0 drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:445 [inline]
 flush_to_ldisc+0x49d/0xf00 drivers/tty/tty_buffer.c:495
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3321
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3402
 kthread+0xd5c/0xf00 kernel/kthread.c:464
 ret_from_fork+0x1e3/0x310 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4154 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_noprof+0x95f/0x1310 mm/slub.c:4340
 kmalloc_noprof include/linux/slab.h:909 [inline]
 tty_buffer_alloc drivers/tty/tty_buffer.c:180 [inline]
 __tty_buffer_request_room+0x3d4/0x7a0 drivers/tty/tty_buffer.c:273
 __tty_insert_flip_string_flags+0x157/0x6f0 drivers/tty/tty_buffer.c:309
 tty_insert_flip_char include/linux/tty_flip.h:77 [inline]
 uart_insert_char+0x368/0x930 drivers/tty/serial/serial_core.c:3514
 serial8250_read_char+0x1ba/0x670 drivers/tty/serial/8250/8250_port.c:1760
 serial8250_rx_chars drivers/tty/serial/8250/8250_port.c:1777 [inline]
 serial8250_handle_irq+0x930/0x1110 drivers/tty/serial/8250/8250_port.c:1941
 serial8250_default_handle_irq+0x116/0x2b0 drivers/tty/serial/8250/8250_port.c:1966
 serial8250_interrupt+0xc8/0x400 drivers/tty/serial/8250/8250_core.c:86
 __handle_irq_event_percpu+0x11c/0xbf0 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
 handle_irq_event+0xe0/0x2a0 kernel/irq/handle.c:210
 handle_edge_irq+0x31c/0xc80 kernel/irq/chip.c:797
 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
 handle_irq arch/x86/kernel/irq.c:254 [inline]
 call_irq_handler arch/x86/kernel/irq.c:266 [inline]
 __common_interrupt+0x9f/0x220 arch/x86/kernel/irq.c:292
 common_interrupt+0x94/0xb0 arch/x86/kernel/irq.c:285
 asm_common_interrupt+0x2b/0x40 arch/x86/include/asm/idtentry.h:693

CPU: 1 UID: 0 PID: 1095 Comm: kworker/u8:6 Not tainted 6.16.0-rc3-syzkaller-00042-g78f4e737a53e #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound flush_to_ldisc
=====================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/24 17:00 upstream 78f4e737a53e 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sixpack_receive_buf
* Struck through repros no longer work on HEAD.