ci2 starts bisection 2025-05-31 08:08:37.712987699 +0000 UTC m=+231307.840864592 bisecting fixing commit since 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 building syzkaller on 16256247d9c41cf4980c36db3841ddd674a04b58 ensuring issue is reproducible on original commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 77b93806e641d186f611c14b4cfda9223e8e24e220b0ed7d9047e6671dda2a57 all runs: crashed: general protection fault in n_tty_flush_buffer representative crash: general protection fault in n_tty_flush_buffer, types: [UNKNOWN] check whether we can drop unnecessary instrumentation disabling configs for [HANG LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP], they are not needed testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: f4c69cb1f221c6554f95ab4bcf43a8b51407ca73c5ab413c5a2bc379c0dd9d69 run #0: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #1: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #2: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #3: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #4: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #5: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #6: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #7: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #8: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #9: OK representative crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer, types: [UNKNOWN] the bug reproduces without the instrumentation disabling configs for [KASAN LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed kconfig minimization: base=4788 full=6023 leaves diff=246 split chunks (needed=false): <246> split chunk #0 of len 246 into 5 parts testing without sub-chunk 1/5 disabling configs for [LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP HANG], they are not needed testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 0b959698ca1f2d3b529e39e6bd1eaeb48019c157953ae4c558d6df6a51d5dfde all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer representative crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [HANG LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP], they are not needed testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: c2d99e79553bb37c1392eb77b4035d13c6728ca6366642cd1f9e53f33fe79868 all runs: OK false negative chance: 0.000 testing without sub-chunk 3/5 disabling configs for [UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP HANG LEAK], they are not needed testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: a93d51acc6532ac4c7b58890460695d3e03123523d0d8b53fbc080314e9d5bb4 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer representative crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 4/5 disabling configs for [LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 21eefd558437f7d9415d5339d750b3b42b27b5a349464b8dd0966b9b1f65ca5e run #0: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #1: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #2: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #3: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #4: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #5: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #6: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #7: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #8: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer run #9: OK representative crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer, types: [UNKNOWN] the chunk can be dropped testing without sub-chunk 5/5 disabling configs for [LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP HANG], they are not needed testing commit 3f5f2283d6843bde6658e93fc50f5f00e5bd3595 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 4b1c6e9414d72804899aa951e8b06f75040662ee7217d0e993bb8d452002a729 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer representative crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer, types: [UNKNOWN] the chunk can be dropped minimized to 50 configs; suspects: [CFG80211 CPU_MITIGATIONS FB HID_HOLTEK HID_PANTHERLORD HID_PENMOUNT HID_PETALYNX HID_PICOLCD_FB HID_PICOLCD_LEDS HID_PID HID_PRIMAX HID_PRODIKEYS HID_RMI HID_SAITEK HID_SAMSUNG HID_SENSOR_CUSTOM_SENSOR HID_SENSOR_HUB HID_SPEEDLINK HID_STEELSERIES HID_SUNPLUS HID_THINGM HID_TIVO HID_TOPSEED HID_TWINHAN HID_WALTOP HID_XINMO HID_ZYDACRON HOLTEK_FF HOTPLUG_PCI HWMON HW_CONSOLE I2C_MUX INPUT_JOYSTICK INPUT_LEDS INPUT_MOUSE INTEGRITY INTEGRITY_AUDIT JOYSTICK_XPAD JOYSTICK_XPAD_FF JOYSTICK_XPAD_LEDS KCOV KCOV_ENABLE_COMPARISONS KCOV_INSTRUMENT_ALL LCD_CLASS_DEVICE LD_IS_BFD LOGIG940_FF LOGIRUMBLEPAD2_FF LOGITECH_FF LOGIWHEELS_FF MAC80211 MAC80211_HAS_RC MAC80211_RC_DEFAULT_MINSTREL MAC80211_RC_MINSTREL MEDIA_ANALOG_TV_SUPPORT MEDIA_ATTACH MEDIA_DIGITAL_TV_SUPPORT MEDIA_RADIO_SUPPORT MEDIA_TUNER MFD_CORE MITIGATION_RFDS NL80211_TESTMODE NOP_USB_XCEIV PANTHERLORD_FF PROC_MEM_ALWAYS_FORCE RADIO_ADAPTERS REGMAP_SPI RFKILL SND SOUND VT WIRELESS] disabling configs for [HANG LEAK UBSAN BUG KASAN LOCKDEP ATOMIC_SLEEP], they are not needed testing current HEAD cf6ed0f1511dde4812a5a30a1450af323934dad9 testing commit cf6ed0f1511dde4812a5a30a1450af323934dad9 gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: e455ad2df63f0a6d18bb09d4ceba9eb7786f1e222f90f44e8d5c853852440a31 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer representative crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer, types: [UNKNOWN] crash still not fixed/happens on the oldest tested release revisions tested: 8, total time: 2h23m43.170991282s (build: 17m13.58071147s, test: 2h4m16.008499928s) crash still not fixed or there were kernel test errors commit msg: Merge android13-5.10 into android13-5.10-lts crash: BUG: unable to handle kernel NULL pointer dereference in n_tty_flush_buffer tty tty1: SAK: killed process 833 (syz.5.145): by fd#3 tty tty1: SAK: killed process 835 (syz.5.145): by fd#3 tty tty1: SAK: killed process 838 (syz.1.148): by fd#3 tty tty1: SAK: killed process 839 (syz.1.148): by fd#3 BUG: kernel NULL pointer dereference, address: 0000000000000010 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 11dfa8067 P4D 11dfa8067 PUD 0 Oops: 0002 [#1] PREEMPT SMP CPU: 1 PID: 432 Comm: kworker/1:10 Not tainted 5.10.237-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events vc_SAK RIP: 0010:reset_buffer_flags drivers/tty/n_tty.c:332 [inline] RIP: 0010:n_tty_flush_buffer+0x36/0xa0 drivers/tty/n_tty.c:370 Code: d0 c2 7e ff 4d 8d ac 24 f0 00 00 00 4c 89 ef e8 30 a1 b5 00 49 8b 94 24 b8 02 00 00 31 c0 b9 40 00 00 00 48 8d b2 60 10 00 00 <48> c7 42 10 00 00 00 00 48 89 f7 48 c7 02 00 00 00 00 48 c7 82 60 RSP: 0018:ffffc90000af7d30 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffff81ae6bb0 RCX: 0000000000000040 RDX: 0000000000000000 RSI: 0000000000001060 RDI: ffff88811923c8f0 RBP: ffffc90000af7d40 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000001000 R12: ffff88811923c800 R13: ffff88811923c8f0 R14: ffff88811923c960 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 000000011d9f3000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tty_buffer_flush+0x10f/0x140 drivers/tty/tty_buffer.c:239 tty_ldisc_flush+0x4c/0xa0 drivers/tty/tty_ldisc.c:415 __do_SAK.part.0+0x1e5/0x230 drivers/tty/tty_io.c:3001 __do_SAK+0x20/0x30 drivers/tty/tty_io.c:2994 vc_SAK+0x43/0xd0 drivers/tty/vt/vt_ioctl.c:994 process_one_work+0x23e/0x500 kernel/workqueue.c:2301 worker_thread+0x5c/0x530 kernel/workqueue.c:2447 kthread+0x196/0x1d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Modules linked in: CR2: 0000000000000010 ---[ end trace 18469a08745cbfcc ]--- RIP: 0010:reset_buffer_flags drivers/tty/n_tty.c:332 [inline] RIP: 0010:n_tty_flush_buffer+0x36/0xa0 drivers/tty/n_tty.c:370 Code: d0 c2 7e ff 4d 8d ac 24 f0 00 00 00 4c 89 ef e8 30 a1 b5 00 49 8b 94 24 b8 02 00 00 31 c0 b9 40 00 00 00 48 8d b2 60 10 00 00 <48> c7 42 10 00 00 00 00 48 89 f7 48 c7 02 00 00 00 00 48 c7 82 60 RSP: 0018:ffffc90000af7d30 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffff81ae6bb0 RCX: 0000000000000040 RDX: 0000000000000000 RSI: 0000000000001060 RDI: ffff88811923c8f0 RBP: ffffc90000af7d40 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000001000 R12: ffff88811923c800 R13: ffff88811923c8f0 R14: ffff88811923c960 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 000000011d9f3000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: d0 c2 rol %dl 2: 7e ff jle 0x3 4: 4d 8d ac 24 f0 00 00 lea 0xf0(%r12),%r13 b: 00 c: 4c 89 ef mov %r13,%rdi f: e8 30 a1 b5 00 call 0xb5a144 14: 49 8b 94 24 b8 02 00 mov 0x2b8(%r12),%rdx 1b: 00 1c: 31 c0 xor %eax,%eax 1e: b9 40 00 00 00 mov $0x40,%ecx 23: 48 8d b2 60 10 00 00 lea 0x1060(%rdx),%rsi * 2a: 48 c7 42 10 00 00 00 movq $0x0,0x10(%rdx) <-- trapping instruction 31: 00 32: 48 89 f7 mov %rsi,%rdi 35: 48 c7 02 00 00 00 00 movq $0x0,(%rdx) 3c: 48 rex.W 3d: c7 .byte 0xc7 3e: 82 (bad) 3f: 60 (bad)