On Thu 31-03-22 16:51:59, chill wrote: > Hello, I found a similar vulnerability in the kernel like this: > https://groups.google.com/g/syzkaller-bugs/c/AHp-BfwUM50/m/Jas1oKfmAAAJ in > the kernel: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.17.tar.xz > REPORT: > ================================================================== > BUG: KASAN: use-after-free in instrument_atomic_read_write > include/linux/instrumented.h:101 [inline] > BUG: KASAN: use-after-free in atomic_try_cmpxchg_acquire > include/linux/atomic/atomic-instrumented.h:541 [inline] > BUG: KASAN: use-after-free in queued_spin_lock > include/asm-generic/qspinlock.h:82 [inline] > BUG: KASAN: use-after-free in do_raw_spin_lock include/linux/spinlock.h:185 > [inline] > BUG: KASAN: use-after-free in __raw_spin_lock > include/linux/spinlock_api_smp.h:134 [inline] > BUG: KASAN: use-after-free in _raw_spin_lock+0x73/0xd0 > kernel/locking/spinlock.c:154 > Write of size 4 at addr ffff8880236f11a0 by task syz-executor.2/9557 > > CPU: 0 PID: 9557 Comm: syz-executor.2 Not tainted 5.17.0-rc6 #1 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 > 04/01/2014 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0x4d/0x66 lib/dump_stack.c:106 > print_address_description.constprop.0+0x1f/0x150 mm/kasan/report.c:255 > __kasan_report mm/kasan/report.c:442 [inline] > kasan_report.cold+0x7f/0x11b mm/kasan/report.c:459 > check_region_inline mm/kasan/generic.c:183 [inline] > kasan_check_range+0xf9/0x1e0 mm/kasan/generic.c:189 > instrument_atomic_read_write include/linux/instrumented.h:101 [inline] > atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:541 > [inline] > queued_spin_lock include/asm-generic/qspinlock.h:82 [inline] > do_raw_spin_lock include/linux/spinlock.h:185 [inline] > __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline] > _raw_spin_lock+0x73/0xd0 kernel/locking/spinlock.c:154 > spin_lock include/linux/spinlock.h:349 [inline] > jbd2_journal_wait_updates+0x1f1/0x280 fs/jbd2/transaction.c:861 > jbd2_journal_lock_updates+0x13a/0x2e0 fs/jbd2/transaction.c:896 > ext4_ioctl_checkpoint fs/ext4/ioctl.c:1085 [inline] > __ext4_ioctl+0xb5b/0x44f0 fs/ext4/ioctl.c:1562 > vfs_ioctl fs/ioctl.c:51 [inline] > __do_sys_ioctl fs/ioctl.c:874 [inline] > __se_sys_ioctl fs/ioctl.c:860 [inline] > __x64_sys_ioctl+0x170/0x1d0 fs/ioctl.c:860 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae Thanks for report. This should be fixed by commit f7f497cb702 ("jbd2: kill t_handle_lock transaction spinlock") which got just merged into 5.18-rc1. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR