RBP: 00007f7accadd0a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f7acbf45fa0 R15: 00007fff0e7a2168 ================================================================== BUG: KASAN: stack-out-of-bounds in iov_iter_revert+0x3ce/0x4e0 lib/iov_iter.c:646 Read of size 8 at addr ffffc90002cd7cb8 by task syz.3.15/3464 CPU: 0 UID: 0 PID: 3464 Comm: syz.3.15 Not tainted 6.12.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x108/0x280 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 iov_iter_revert+0x3ce/0x4e0 lib/iov_iter.c:646 fuse_direct_io+0x2c63/0x2ce0 fs/fuse/file.c:1670 fuse_direct_write_iter fs/fuse/file.c:1745 [inline] fuse_file_write_iter+0x683/0xdd0 fs/fuse/file.c:1790 do_iter_readv_writev+0x43d/0x6e0 vfs_writev+0x428/0xd20 fs/read_write.c:1064 do_writev+0x150/0x280 fs/read_write.c:1111 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x8d/0x170 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7acbd80809 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7accadd058 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f7acbf45fa0 RCX: 00007f7acbd80809 RDX: 0000000000000002 RSI: 0000000020000180 RDI: 0000000000000004 RBP: 00007f7accadd0a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f7acbf45fa0 R15: 00007fff0e7a2168 The buggy address belongs to stack of task syz.3.15/3464 and is located at offset 24 in frame: vfs_writev+0x0/0xd20 This frame has 3 objects: [32, 160) 'iovstack' [192, 200) 'iov' [224, 264) 'iter' The buggy address belongs to the virtual mapping at [ffffc90002cd0000, ffffc90002cd9000) created by: copy_process+0x40b/0x3620 kernel/fork.c:2206 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88817aa95000 pfn:0x17aa95 memcg:ffff88810c389d02 flags: 0x100000000000000(node=0|zone=2) raw: 0100000000000000 0000000000000000 dead000000000122 0000000000000000 raw: ffff88817aa95000 0000000000000000 00000001ffffffff ffff88810c389d02 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 368, tgid 368 (kworker/u8:5), ts 76208457103, free_ts 75539682710 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x10f/0x130 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x4213/0x43f0 mm/page_alloc.c:3457 __alloc_pages_noprof+0x256/0x670 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x289/0x4e0 mm/mempolicy.c:2265 vm_area_alloc_pages mm/vmalloc.c:3568 [inline] __vmalloc_area_node mm/vmalloc.c:3646 [inline] __vmalloc_node_range_noprof+0x68f/0xfd0 mm/vmalloc.c:3828 alloc_thread_stack_node kernel/fork.c:314 [inline] dup_task_struct+0x5ee/0x740 kernel/fork.c:1115 copy_process+0x40b/0x3620 kernel/fork.c:2206 kernel_clone+0x195/0x720 kernel/fork.c:2787 user_mode_thread+0x12d/0x190 kernel/fork.c:2865 call_usermodehelper_exec_sync kernel/umh.c:133 [inline] call_usermodehelper_exec_work+0x78/0x1c0 kernel/umh.c:164 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x8ea/0x1360 kernel/workqueue.c:3310 worker_thread+0x868/0xc70 kernel/workqueue.c:3391 kthread+0x26a/0x2c0 kernel/kthread.c:389 ret_from_fork+0x34/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 page last free pid 8 tgid 8 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xa9b/0xc60 mm/page_alloc.c:2638 vfree+0x10e/0x210 mm/vmalloc.c:3361 delayed_vfree_work+0x3c/0x70 mm/vmalloc.c:3282 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x8ea/0x1360 kernel/workqueue.c:3310 worker_thread+0x868/0xc70 kernel/workqueue.c:3391 kthread+0x26a/0x2c0 kernel/kthread.c:389 ret_from_fork+0x34/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffffc90002cd7b80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90002cd7c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90002cd7c80: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 00 00 00 00 ^ ffffc90002cd7d00: 00 00 00 00 00 00 00 00 f2 f2 f2 f2 00 f2 f2 f2 ffffc90002cd7d80: 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3 00 00 00 00 ==================================================================