Hello, syzbot found the following issue on: HEAD commit: 8867bbd4a056 mm: arm64: Fix the out-of-bounds issue in con.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=11626d7d980000 kernel config: https://syzkaller.appspot.com/x/.config?x=1bc88a9f65787e86 dashboard link: https://syzkaller.appspot.com/bug?extid=622acb507894a48b2ce9 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/5ef30d34e749/disk-8867bbd4.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/a21c2389ebfb/vmlinux-8867bbd4.xz kernel image: https://storage.googleapis.com/syzbot-assets/9720b12c3f99/Image-8867bbd4.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+622acb507894a48b2ce9@xxxxxxxxxxxxxxxxxxxxxxxxx sp0: Synchronizing with TNC ------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Tainted: G W ------------------------------------------------------ syz.2.1398/12737 is trying to acquire lock: ffff80008f58d020 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x88/0xec kernel/printk/printk.c:1866 but task is already holding lock: ffff800094049db8 (&port_lock_key){-.-.}-{2:2}, at: uart_port_lock_irqsave include/linux/serial_core.h:618 [inline] ffff800094049db8 (&port_lock_key){-.-.}-{2:2}, at: uart_write+0x114/0x2ec drivers/tty/serial/serial_core.c:624 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&port_lock_key){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:618 [inline] pl011_console_write+0x148/0x724 drivers/tty/serial/amba-pl011.c:2316 console_emit_next_record kernel/printk/printk.c:2928 [inline] console_flush_all+0x5cc/0xb74 kernel/printk/printk.c:2994 console_unlock+0xec/0x3d4 kernel/printk/printk.c:3063 vprintk_emit+0x1ec/0x350 kernel/printk/printk.c:2345 vprintk_default+0xa0/0xe4 kernel/printk/printk.c:2360 vprintk+0x200/0x2d4 kernel/printk/printk_safe.c:45 _printk+0xdc/0x128 kernel/printk/printk.c:2370 register_console+0x700/0xa8c kernel/printk/printk.c:3596 uart_configure_port drivers/tty/serial/serial_core.c:2664 [inline] serial_core_add_one_port drivers/tty/serial/serial_core.c:3192 [inline] serial_core_register_port+0x1428/0x1bf4 drivers/tty/serial/serial_core.c:3429 serial_ctrl_register_port+0x28/0x38 drivers/tty/serial/serial_ctrl.c:41 uart_add_one_port+0x28/0x38 drivers/tty/serial/serial_port.c:136 pl011_register_port+0x1b4/0x44c drivers/tty/serial/amba-pl011.c:2744 sbsa_uart_probe+0x488/0x608 drivers/tty/serial/amba-pl011.c:2914 platform_probe+0x148/0x1c0 drivers/base/platform.c:1404 really_probe+0x38c/0x8fc drivers/base/dd.c:656 __driver_probe_device+0x194/0x374 drivers/base/dd.c:798 driver_probe_device+0x78/0x330 drivers/base/dd.c:828 __device_attach_driver+0x2a8/0x4f4 drivers/base/dd.c:956 bus_for_each_drv+0x228/0x2bc drivers/base/bus.c:457 __device_attach+0x2b4/0x434 drivers/base/dd.c:1028 device_initial_probe+0x24/0x34 drivers/base/dd.c:1077 bus_probe_device+0x178/0x240 drivers/base/bus.c:532 device_add+0x728/0xa6c drivers/base/core.c:3721 platform_device_add+0x3e8/0x6e8 drivers/base/platform.c:716 platform_device_register_full+0x4ec/0x604 drivers/base/platform.c:844 acpi_create_platform_device+0x5bc/0x744 drivers/acpi/acpi_platform.c:177 acpi_default_enumeration+0x6c/0xdc drivers/acpi/scan.c:2184 acpi_bus_attach+0x8b8/0xaa8 drivers/acpi/scan.c:2293 acpi_dev_for_one_check+0xa0/0xb4 drivers/acpi/bus.c:1143 device_for_each_child+0xec/0x174 drivers/base/core.c:4050 acpi_dev_for_each_child+0xc4/0x108 drivers/acpi/bus.c:1155 acpi_bus_attach+0x358/0xaa8 drivers/acpi/scan.c:2298 acpi_dev_for_one_check+0xa0/0xb4 drivers/acpi/bus.c:1143 device_for_each_child+0xec/0x174 drivers/base/core.c:4050 acpi_dev_for_each_child+0xc4/0x108 drivers/acpi/bus.c:1155 acpi_bus_attach+0x358/0xaa8 drivers/acpi/scan.c:2298 acpi_bus_scan+0x118/0x4f0 drivers/acpi/scan.c:2579 acpi_scan_init+0x214/0x6b0 drivers/acpi/scan.c:2714 acpi_init+0x190/0x254 drivers/acpi/bus.c:1460 do_one_initcall+0x254/0x9e4 init/main.c:1267 do_initcall_level+0x154/0x214 init/main.c:1329 do_initcalls+0x58/0xac init/main.c:1345 do_basic_setup+0x8c/0xa0 init/main.c:1364 kernel_init_freeable+0x324/0x478 init/main.c:1578 kernel_init+0x24/0x2a0 init/main.c:1467 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 -> #0 (console_owner){-.-.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x3384/0x763c kernel/locking/lockdep.c:5137 lock_acquire+0x248/0x73c kernel/locking/lockdep.c:5754 console_lock_spinning_enable+0xb4/0xec kernel/printk/printk.c:1870 console_emit_next_record kernel/printk/printk.c:2922 [inline] console_flush_all+0x58c/0xb74 kernel/printk/printk.c:2994 console_unlock+0xec/0x3d4 kernel/printk/printk.c:3063 vprintk_emit+0x1ec/0x350 kernel/printk/printk.c:2345 vprintk_default+0xa0/0xe4 kernel/printk/printk.c:2360 vprintk+0x200/0x2d4 kernel/printk/printk_safe.c:45 _printk+0xdc/0x128 kernel/printk/printk.c:2370 __report_bug lib/bug.c:195 [inline] report_bug+0x3b8/0x5b0 lib/bug.c:219 bug_handler+0x50/0x1fc arch/arm64/kernel/traps.c:978 call_break_hook arch/arm64/kernel/debug-monitors.c:321 [inline] brk_handler+0x17c/0x2e0 arch/arm64/kernel/debug-monitors.c:328 do_debug_exception+0x1e4/0x398 arch/arm64/mm/fault.c:909 el1_dbg+0x64/0x80 arch/arm64/kernel/entry-common.c:472 el1h_64_sync_handler+0x40/0xac arch/arm64/kernel/entry-common.c:512 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:593 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:669 [inline] uart_write+0x280/0x2ec drivers/tty/serial/serial_core.c:626 tnc_init drivers/net/hamradio/6pack.c:531 [inline] sixpack_open+0x5d8/0x8b0 drivers/net/hamradio/6pack.c:628 tty_ldisc_open+0x9c/0x14c drivers/tty/tty_ldisc.c:432 tty_set_ldisc+0x2f8/0x4e0 drivers/tty/tty_ldisc.c:563 tiocsetd+0x100/0x13c drivers/tty/tty_io.c:2439 tty_ioctl+0xba0/0xd8c drivers/tty/tty_io.c:2739 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&port_lock_key); lock(console_owner); lock(&port_lock_key); lock(console_owner); *** DEADLOCK *** 5 locks held by syz.2.1398/12737: #0: ffff0000ed2011c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_lock+0x78/0xc8 drivers/tty/tty_mutex.c:18 #1: ffff0000ed2010a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_write+0x3c/0x4c drivers/tty/tty_ldsem.c:366 #2: ffff800094049db8 (&port_lock_key){-.-.}-{2:2}, at: uart_port_lock_irqsave include/linux/serial_core.h:618 [inline] #2: ffff800094049db8 (&port_lock_key){-.-.}-{2:2}, at: uart_write+0x114/0x2ec drivers/tty/serial/serial_core.c:624 #3: ffff80008f474940 (console_lock){+.+.}-{0:0}, at: vprintk_emit+0x1d0/0x350 kernel/printk/printk.c:2344 #4: ffff80008f474570 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire+0x10/0x4c include/linux/rcupdate.h:333 stack backtrace: CPU: 0 PID: 12737 Comm: syz.2.1398 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114 dump_stack+0x1c/0x28 lib/dump_stack.c:123 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2060 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x3384/0x763c kernel/locking/lockdep.c:5137 lock_acquire+0x248/0x73c kernel/locking/lockdep.c:5754 console_lock_spinning_enable+0xb4/0xec kernel/printk/printk.c:1870 console_emit_next_record kernel/printk/printk.c:2922 [inline] console_flush_all+0x58c/0xb74 kernel/printk/printk.c:2994 console_unlock+0xec/0x3d4 kernel/printk/printk.c:3063 vprintk_emit+0x1ec/0x350 kernel/printk/printk.c:2345 vprintk_default+0xa0/0xe4 kernel/printk/printk.c:2360 vprintk+0x200/0x2d4 kernel/printk/printk_safe.c:45 _printk+0xdc/0x128 kernel/printk/printk.c:2370 __report_bug lib/bug.c:195 [inline] report_bug+0x3b8/0x5b0 lib/bug.c:219 bug_handler+0x50/0x1fc arch/arm64/kernel/traps.c:978 call_break_hook arch/arm64/kernel/debug-monitors.c:321 [inline] brk_handler+0x17c/0x2e0 arch/arm64/kernel/debug-monitors.c:328 do_debug_exception+0x1e4/0x398 arch/arm64/mm/fault.c:909 el1_dbg+0x64/0x80 arch/arm64/kernel/entry-common.c:472 el1h_64_sync_handler+0x40/0xac arch/arm64/kernel/entry-common.c:512 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:593 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:669 [inline] uart_write+0x280/0x2ec drivers/tty/serial/serial_core.c:626 tnc_init drivers/net/hamradio/6pack.c:531 [inline] sixpack_open+0x5d8/0x8b0 drivers/net/hamradio/6pack.c:628 tty_ldisc_open+0x9c/0x14c drivers/tty/tty_ldisc.c:432 tty_set_ldisc+0x2f8/0x4e0 drivers/tty/tty_ldisc.c:563 tiocsetd+0x100/0x13c drivers/tty/tty_io.c:2439 tty_ioctl+0xba0/0xd8c drivers/tty/tty_io.c:2739 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 WARNING: CPU: 0 PID: 12737 at drivers/tty/serial/serial_core.c:625 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] WARNING: CPU: 0 PID: 12737 at drivers/tty/serial/serial_core.c:625 uart_port_unlock_irqrestore include/linux/serial_core.h:669 [inline] WARNING: CPU: 0 PID: 12737 at drivers/tty/serial/serial_core.c:625 uart_write+0x280/0x2ec drivers/tty/serial/serial_core.c:626 Modules linked in: CPU: 0 PID: 12737 Comm: syz.2.1398 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 pstate: 804000c5 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : uart_write+0x280/0x2ec include/linux/spinlock.h:406 lr : uart_write+0x278/0x2ec drivers/tty/serial/serial_core.c:625 sp : ffff800097fc7ad0 x29: ffff800097fc7ad0 x28: 1ffff00012ff8f68 x27: dfff800000000000 x26: 0000000000000001 x25: dfff800000000000 x24: ffff0000c9708f48 x23: 0000000000000000 x22: ffff800094049da0 x21: ffff800097fc7b60 x20: 0000000000000001 x19: ffff0000c9708be8 x18: ffff800097fc7780 x17: 00000000000411dd x16: ffff8000803514ec x15: ffff700012ff8f40 x14: 1ffff00012ff8f40 x13: 0000000000000004 x12: ffffffffffffffff x11: 0000000000040000 x10: 000000000001f74c x9 : ffff8000ab01c000 x8 : 000000000001f74d x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000020 x4 : 0000000000000000 x3 : ffff80008035161c x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffff800094049da0 Call trace: spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:669 [inline] uart_write+0x280/0x2ec drivers/tty/serial/serial_core.c:626 tnc_init drivers/net/hamradio/6pack.c:531 [inline] sixpack_open+0x5d8/0x8b0 drivers/net/hamradio/6pack.c:628 tty_ldisc_open+0x9c/0x14c drivers/tty/tty_ldisc.c:432 tty_set_ldisc+0x2f8/0x4e0 drivers/tty/tty_ldisc.c:563 tiocsetd+0x100/0x13c drivers/tty/tty_io.c:2439 tty_ioctl+0xba0/0xd8c drivers/tty/tty_io.c:2739 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 irq event stamp: 1952 hardirqs last enabled at (1951): [<ffff8000803794d8>] __up_console_sem kernel/printk/printk.c:341 [inline] hardirqs last enabled at (1951): [<ffff8000803794d8>] __console_unlock kernel/printk/printk.c:2746 [inline] hardirqs last enabled at (1951): [<ffff8000803794d8>] console_unlock+0x17c/0x3d4 kernel/printk/printk.c:3065 hardirqs last disabled at (1952): [<ffff80008b2f9ba8>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (1952): [<ffff80008b2f9ba8>] _raw_spin_lock_irqsave+0x2c/0x7c kernel/locking/spinlock.c:162 softirqs last enabled at (1800): [<ffff8000893ef2dc>] neigh_parms_alloc+0x330/0x464 net/core/neighbour.c:1738 softirqs last disabled at (1798): [<ffff8000893ef230>] neigh_parms_alloc+0x284/0x464 net/core/neighbour.c:1736 ---[ end trace 0000000000000000 ]--- --- This report is generated by a bot. 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