================================================================== BUG: KASAN: use-after-free in bio_poll+0x275/0x3c0 block/blk-core.c:942 Read of size 4 at addr ffff8880760c3174 by task syz-executor.1/8717 CPU: 0 PID: 8717 Comm: syz-executor.1 Not tainted 5.18.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 bio_poll+0x275/0x3c0 block/blk-core.c:942 __iomap_dio_rw+0x10ee/0x1ae0 fs/iomap/direct-io.c:658 iomap_dio_rw+0x38/0x90 fs/iomap/direct-io.c:681 ext4_dio_write_iter fs/ext4/file.c:566 [inline] ext4_file_write_iter+0xe4d/0x1510 fs/ext4/file.c:677 call_write_iter include/linux/fs.h:2050 [inline] do_iter_readv_writev+0x3d1/0x640 fs/read_write.c:726 do_iter_write+0x182/0x700 fs/read_write.c:852 vfs_writev+0x1aa/0x630 fs/read_write.c:925 do_pwritev+0x1b6/0x270 fs/read_write.c:1022 __do_sys_pwritev2 fs/read_write.c:1081 [inline] __se_sys_pwritev2 fs/read_write.c:1072 [inline] __x64_sys_pwritev2+0xeb/0x150 fs/read_write.c:1072 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd3a4e890e9 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd3a5fc9168 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007fd3a4f9bf60 RCX: 00007fd3a4e890e9 RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000004 RBP: 00007fd3a4ee308d R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000001400 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd60e1412f R14: 00007fd3a5fc9300 R15: 0000000000022000 Allocated by task 3648: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x204/0x3b0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] locks_alloc_lock fs/locks.c:270 [inline] flock_make_lock fs/locks.c:409 [inline] __do_sys_flock+0x188/0x7a0 fs/locks.c:2075 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 3648: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kmem_cache_free+0xdd/0x5a0 mm/slub.c:3527 locks_free_lock fs/locks.c:307 [inline] __do_sys_flock+0x52d/0x7a0 fs/locks.c:2096 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8880760c3150 which belongs to the cache file_lock_cache of size 272 The buggy address is located 36 bytes inside of 272-byte region [ffff8880760c3150, ffff8880760c3260) The buggy address belongs to the physical page: page:ffffea0001d830c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x760c3 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff8881400f6dc0 raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 4121, tgid 4121 (udevd), ts 230350837902, free_ts 230337614262 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x360/0x3b0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] locks_alloc_lock fs/locks.c:270 [inline] flock_lock_inode+0x16e/0xf60 fs/locks.c:996 flock_lock_inode_wait+0xf5/0x230 fs/locks.c:1992 locks_lock_inode_wait fs/locks.c:2019 [inline] locks_lock_file_wait include/linux/fs.h:1326 [inline] __do_sys_flock+0x6c2/0x7a0 fs/locks.c:2093 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0x7b1/0x1880 kernel/rcu/tree.c:2786 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Memory state around the buggy address: ffff8880760c3000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880760c3080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880760c3100: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb ^ ffff8880760c3180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880760c3200: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================