8<--- cut here --- Unable to handle kernel paging request at virtual address fee00001 [fee00001] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 5299 Comm: syz-executor.1 Not tainted 5.17.0-rc8-syzkaller #0 Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at io_serial_out+0x38/0x40 drivers/tty/serial/8250/8250_port.c:458 LR is at io_serial_out+0x24/0x40 drivers/tty/serial/8250/8250_port.c:458 pc : [<808e1c90>] lr : [<808e1c7c>] psr: 60000093 sp : 8509fd48 ip : 8509fd48 fp : 8509fd64 r10: 00000001 r9 : 00000fff r8 : 85752c00 r7 : a0000013 r6 : 824f1390 r5 : 00000002 r4 : fee00001 r3 : 00000000 r2 : 00000002 r1 : 00000000 r0 : 824f1390 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 88e35040 DAC: 00000000 Register r0 information: non-slab/vmalloc memory Register r1 information: NULL pointer Register r2 information: non-paged memory Register r3 information: NULL pointer Register r4 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1028 Register r5 information: non-paged memory Register r6 information: non-slab/vmalloc memory Register r7 information: non-slab/vmalloc memory Register r8 information: slab kmalloc-512 start 85752c00 pointer offset 0 size 512 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: non-slab/vmalloc memory Register r12 information: non-slab/vmalloc memory Process syz-executor.1 (pid: 5299, stack limit = 0x8509e000) Stack: (0x8509fd48 to 0x850a0000) fd40: 824f1390 00000000 824f1390 a0000013 8509fd94 8509fd68 fd60: 808e3ac8 808e1c64 00001244 ebfaf000 85752c00 824f1390 00000001 85752c00 fd80: 824f1390 a0000013 8509fda4 8509fd98 808dac5c 808e3998 8509fdc4 8509fda8 fda0: 808dd014 808dac18 ebfad000 ebfaf26c 00000008 ebfad000 8509fdd4 8509fdc8 fdc0: 808dd084 808dcfb0 8509fe54 8509fdd8 808bd89c 808dd080 00000000 ffffffff fde0: ffffffff 00000000 ffffffff 85752c74 00000001 00000fff 819082b0 55555556 fe00: 00000000 00000000 ebfaf000 8509fe7c 00000001 8509fe7c 00000000 ebfad000 fe20: 00000001 8509fe7c 806782fc 00000000 847a7e00 85752c00 808be7a0 00000009 fe40: 20000080 85752c00 8509fe6c 8509fe58 808be7bc 808bd4c0 00000000 816df01c fe60: 8509ff14 8509fe70 808b9828 808be7ac 00000000 e7cfbc9f 08003231 00000000 fe80: 00000012 00000001 83cff348 88e37cc0 00000003 00000036 8509fef4 8509fea8 fea0: 80687f20 8067dd60 00000001 00000054 00000012 8509fec4 83822cd0 82c7a3b8 fec0: 20005412 88e37c0b 8509feb8 88e37cc0 00000003 e7cfbc9f 81f290f0 20000080 fee0: 88e37cc0 e7cfbc9f 8509ff14 00005412 00000000 88e37cc1 20000080 88e37cc0 ff00: 00000003 83cff348 8509ffa4 8509ff18 804a4928 808b9010 820a55ec 8209f3b0 ff20: 0012bfc8 829b0b80 829b12a0 820a55f0 00000036 60000010 820a55e8 829b0b80 ff40: 820a55f0 00000036 8509ff64 8509ff58 816dae08 816dacd4 8509ff84 8509ff68 ff60: 816dab90 816dadf8 60000013 00000000 0012bfc8 e7cfbc9f 8509ff9c 00000000 ff80: 00000000 0012bfc8 00000036 802002a4 829b0b80 00000036 00000000 8509ffa8 ffa0: 80200060 804a4824 00000000 00000000 00000003 00005412 20000080 00000000 ffc0: 00000000 00000000 0012bfc8 00000036 7e87c312 76ffc6d0 7e87c4a4 76ffc20c ffe0: 76ffc020 76ffc010 000163a0 0004bf80 60000010 00000003 00000000 00000000 Backtrace: [<808e1c58>] (io_serial_out) from [<808e3ac8>] (serial_out drivers/tty/serial/8250/8250.h:120 [inline]) [<808e1c58>] (io_serial_out) from [<808e3ac8>] (serial8250_set_THRI drivers/tty/serial/8250/8250.h:140 [inline]) [<808e1c58>] (io_serial_out) from [<808e3ac8>] (__start_tx drivers/tty/serial/8250/8250_port.c:1568 [inline]) [<808e1c58>] (io_serial_out) from [<808e3ac8>] (serial8250_start_tx+0x13c/0x234 drivers/tty/serial/8250/8250_port.c:1667) r7:a0000013 r6:824f1390 r5:00000000 r4:824f1390 [<808e398c>] (serial8250_start_tx) from [<808dac5c>] (__uart_start+0x50/0x54 drivers/tty/serial/serial_core.c:127) r7:a0000013 r6:824f1390 r5:85752c00 r4:00000001 [<808dac0c>] (__uart_start) from [<808dd014>] (uart_start+0x70/0xd0 drivers/tty/serial/serial_core.c:137) [<808dcfa4>] (uart_start) from [<808dd084>] (uart_flush_chars+0x10/0x14 drivers/tty/serial/serial_core.c:548) r7:ebfad000 r6:00000008 r5:ebfaf26c r4:ebfad000 [<808dd074>] (uart_flush_chars) from [<808bd89c>] (__receive_buf drivers/tty/n_tty.c:1553 [inline]) [<808dd074>] (uart_flush_chars) from [<808bd89c>] (n_tty_receive_buf_common+0x3e8/0x12c8 drivers/tty/n_tty.c:1645) [<808bd4b4>] (n_tty_receive_buf_common) from [<808be7bc>] (n_tty_receive_buf+0x1c/0x24 drivers/tty/n_tty.c:1674) r10:85752c00 r9:20000080 r8:00000009 r7:808be7a0 r6:85752c00 r5:847a7e00 r4:00000000 [<808be7a0>] (n_tty_receive_buf) from [<808b9828>] (tiocsti drivers/tty/tty_io.c:2293 [inline]) [<808be7a0>] (n_tty_receive_buf) from [<808b9828>] (tty_ioctl+0x824/0xa90 drivers/tty/tty_io.c:2692) [<808b9004>] (tty_ioctl) from [<804a4928>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<808b9004>] (tty_ioctl) from [<804a4928>] (do_vfs_ioctl fs/ioctl.c:834 [inline]) [<808b9004>] (tty_ioctl) from [<804a4928>] (__do_sys_ioctl fs/ioctl.c:872 [inline]) [<808b9004>] (tty_ioctl) from [<804a4928>] (sys_ioctl+0x110/0xaa0 fs/ioctl.c:860) r10:83cff348 r9:00000003 r8:88e37cc0 r7:20000080 r6:88e37cc1 r5:00000000 r4:00005412 [<804a4818>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:64) Exception stack(0x8509ffa8 to 0x8509fff0) ffa0: 00000000 00000000 00000003 00005412 20000080 00000000 ffc0: 00000000 00000000 0012bfc8 00000036 7e87c312 76ffc6d0 7e87c4a4 76ffc20c ffe0: 76ffc020 76ffc010 000163a0 0004bf80 r10:00000036 r9:829b0b80 r8:802002a4 r7:00000036 r6:0012bfc8 r5:00000000 r4:00000000 Code: e6ef5075 e0844001 e7f34054 e2444612 (e5c45000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef5075 uxtb r5, r5 4: e0844001 add r4, r4, r1 8: e7f34054 ubfx r4, r4, #0, #20 c: e2444612 sub r4, r4, #18874368 ; 0x1200000 * 10: e5c45000 strb r5, [r4] <-- trapping instruction