Hello, syzbot found the following issue on: HEAD commit: c5eb0a61238d Linux 5.18-rc6 git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=112bf03ef00000 kernel config: https://syzkaller.appspot.com/x/.config?x=79caa0035f59d385 dashboard link: https://syzkaller.appspot.com/bug?extid=99938118dfd9e1b0741a compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12311571f00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=177a2e86f00000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+99938118dfd9e1b0741a@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in bio_poll+0x275/0x3c0 block/blk-core.c:942 Read of size 4 at addr ffff8880751d92b4 by task syz-executor486/3607 CPU: 0 PID: 3607 Comm: syz-executor486 Not tainted 5.18.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __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: 0033:0x7f6846af7e69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffe8df3bb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 0000000000008ff2 RCX: 00007f6846af7e69 RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000001400 R11: 0000000000000246 R12: 00007fffe8df3bdc R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 </TASK> The buggy address belongs to the physical page: page:ffffea0001d47640 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x751d9 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001e3d2c8 ffffea00008b7a48 0000000000000000 raw: 0000000000000000 00000000000c0000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x92880(GFP_NOWAIT|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 3605, tgid 3605 (syz-executor486), ts 36797088171, free_ts 37121806576 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 mempool_alloc+0x146/0x350 mm/mempool.c:392 bio_alloc_bioset+0x31d/0x4e0 block/bio.c:492 bio_alloc include/linux/bio.h:426 [inline] iomap_dio_bio_iter+0x9bc/0x14c0 fs/iomap/direct-io.c:314 iomap_dio_iter fs/iomap/direct-io.c:435 [inline] __iomap_dio_rw+0x84a/0x1ae0 fs/iomap/direct-io.c:591 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 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: ffff8880751d9180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880751d9200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880751d9280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880751d9300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880751d9380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. 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