================================================================== BUG: KASAN: null-ptr-deref in copy_to_user arch/x86/include/asm/uaccess.h:731 [inline] BUG: KASAN: null-ptr-deref in snd_timer_user_read+0x594/0x710 sound/core/timer.c:2006 Read of size 32 at addr (null) by task syz-executor4/7129 CPU: 0 PID: 7129 Comm: syz-executor4 Not tainted 4.9.141+ #23 ffff8801c5e47958 ffffffff81b42e79 0000000000000000 0000000000000020 0000000000000000 ffff8801c5e47b28 ffff8801ca32cf00 ffff8801c5e479a0 ffffffff81500bed ffffffff8224e014 0000000000000282 aad78a5430ede23b Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] kasan_report_error mm/kasan/report.c:353 [inline] [] kasan_report.cold.6+0x6d/0x2fe mm/kasan/report.c:412 [] check_memory_region_inline mm/kasan/kasan.c:318 [inline] [] check_memory_region+0x14d/0x1b0 mm/kasan/kasan.c:325 [] kasan_check_read+0x11/0x20 mm/kasan/kasan.c:330 [] copy_to_user arch/x86/include/asm/uaccess.h:731 [inline] [] snd_timer_user_read+0x594/0x710 sound/core/timer.c:2006 [] do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718 [] do_loop_readv_writev fs/read_write.c:707 [inline] [] compat_do_readv_writev+0x570/0x7b0 fs/read_write.c:1091 [] compat_readv+0xe2/0x150 fs/read_write.c:1120 [] do_compat_readv+0xf2/0x1d0 fs/read_write.c:1140 [] C_SYSC_readv fs/read_write.c:1152 [inline] [] compat_SyS_readv+0x26/0x30 fs/read_write.c:1148 [] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline] [] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390 [] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 7129 Comm: syz-executor4 Tainted: G B 4.9.141+ #23 ffff8801c5e47880 ffffffff81b42e79 ffffffff82e37630 00000000ffffffff 0000000000000000 0000000000000000 ffff8801ca32cf00 ffff8801c5e47940 ffffffff813f7125 0000000041b58ab3 ffffffff82e2b62b ffffffff813f6f66 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] panic+0x1bf/0x39f kernel/panic.c:179 [] kasan_end_report+0x47/0x4f mm/kasan/report.c:180 [] kasan_report_error mm/kasan/report.c:360 [inline] [] kasan_report.cold.6+0x76/0x2fe mm/kasan/report.c:412 [] check_memory_region_inline mm/kasan/kasan.c:318 [inline] [] check_memory_region+0x14d/0x1b0 mm/kasan/kasan.c:325 [] kasan_check_read+0x11/0x20 mm/kasan/kasan.c:330 [] copy_to_user arch/x86/include/asm/uaccess.h:731 [inline] [] snd_timer_user_read+0x594/0x710 sound/core/timer.c:2006 [] do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718 [] do_loop_readv_writev fs/read_write.c:707 [inline] [] compat_do_readv_writev+0x570/0x7b0 fs/read_write.c:1091 [] compat_readv+0xe2/0x150 fs/read_write.c:1120 [] do_compat_readv+0xf2/0x1d0 fs/read_write.c:1140 [] C_SYSC_readv fs/read_write.c:1152 [inline] [] compat_SyS_readv+0x26/0x30 fs/read_write.c:1148 [] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline] [] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390 [] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137 Kernel Offset: disabled Rebooting in 86400 seconds..