------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 28034 at lib/refcount.c:28 refcount_warn_saturate+0x1a0/0x1c8 lib/refcount.c:28 Modules linked in: CPU: 1 PID: 28034 Comm: syz-executor.5 Not tainted 6.1.0-rc8-syzkaller-33330-ga5541c0811a0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : refcount_warn_saturate+0x1a0/0x1c8 lib/refcount.c:28 lr : refcount_warn_saturate+0x1a0/0x1c8 lib/refcount.c:28 sp : ffff8000139d3b40 x29: ffff8000139d3b40 x28: 00000000000000b4 x27: ffff00013462e800 x26: 0000000000000004 x25: 0000000000000000 x24: ffff000116f5d800 x23: 0000000000000001 x22: ffff00013462e800 x21: 0000000000000000 x20: 0000000000000003 x19: ffff80000d95e000 x18: 000000000000025d x17: 0000000000000000 x16: ffff80000dbe6158 x15: ffff00011685b480 x14: 0000000000000000 x13: 00000000ffffffff x12: 0000000000040000 x11: 0000000000001915 x10: ffff800019301000 x9 : 684d606260599000 x8 : 684d606260599000 x7 : ffff80000816678c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff8000139d37b8 x1 : 0000000100000000 x0 : 0000000000000026 Call trace: refcount_warn_saturate+0x1a0/0x1c8 lib/refcount.c:28 __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] kref_put include/linux/kref.h:64 [inline] __drm_gem_object_put include/drm/drm_gem.h:430 [inline] drm_gem_object_put include/drm/drm_gem.h:443 [inline] drm_gem_object_handle_put_unlocked+0x178/0x1a0 drivers/gpu/drm/drm_gem.c:226 drm_gem_object_release_handle drivers/gpu/drm/drm_gem.c:245 [inline] drm_gem_handle_delete+0xb4/0xf0 drivers/gpu/drm/drm_gem.c:273 drm_gem_dumb_destroy+0x28/0x38 drivers/gpu/drm/drm_gem.c:329 drm_mode_destroy_dumb drivers/gpu/drm/drm_dumb_buffers.c:145 [inline] drm_mode_destroy_dumb_ioctl+0x74/0x88 drivers/gpu/drm/drm_dumb_buffers.c:153 drm_ioctl_kernel+0x19c/0x250 drivers/gpu/drm/drm_ioctl.c:788 drm_ioctl+0x3a4/0x5cc drivers/gpu/drm/drm_ioctl.c:891 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 irq event stamp: 88 hardirqs last enabled at (87): [] raw_spin_rq_unlock_irq kernel/sched/sched.h:1366 [inline] hardirqs last enabled at (87): [] finish_lock_switch+0x94/0xe8 kernel/sched/core.c:4968 hardirqs last disabled at (88): [] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405 softirqs last enabled at (8): [] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (6): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- loop5: detected capacity change from 0 to 512 EXT2-fs (loop5): (no)acl options not supported