On Mon, Nov 25, 2024 at 2:27 PM syzbot <syzbot+8d1206605b05ca9a0e6a@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 85a2dd7d7c81 Add linux-next specific files for 20241125 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=10b52778580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=45719eec4c74e6ba > dashboard link: https://syzkaller.appspot.com/bug?extid=8d1206605b05ca9a0e6a > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10b46530580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1578dee8580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/5422dd6ada68/disk-85a2dd7d.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/3a382ed71d3a/vmlinux-85a2dd7d.xz > kernel image: https://storage.googleapis.com/syzbot-assets/9b4d03eb0da3/bzImage-85a2dd7d.xz > mounted in repro: https://storage.googleapis.com/syzbot-assets/29b16c7eaa78/mount_0.gz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+8d1206605b05ca9a0e6a@xxxxxxxxxxxxxxxxxxxxxxxxx > > ================================================================== > BUG: KASAN: slab-out-of-bounds in ovl_upperdentry_dereference fs/overlayfs/ovl_entry.h:195 [inline] > BUG: KASAN: slab-out-of-bounds in ovl_i_dentry_upper fs/overlayfs/util.c:366 [inline] > BUG: KASAN: slab-out-of-bounds in ovl_inode_upper+0x36/0x80 fs/overlayfs/util.c:386 > Read of size 8 at addr ffff88807df938e0 by task syz-executor150/5827 > > CPU: 0 UID: 0 PID: 5827 Comm: syz-executor150 Not tainted 6.12.0-next-20241125-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:94 [inline] > dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 > print_address_description mm/kasan/report.c:378 [inline] > print_report+0x169/0x550 mm/kasan/report.c:489 > kasan_report+0x143/0x180 mm/kasan/report.c:602 > ovl_upperdentry_dereference fs/overlayfs/ovl_entry.h:195 [inline] > ovl_i_dentry_upper fs/overlayfs/util.c:366 [inline] > ovl_inode_upper+0x36/0x80 fs/overlayfs/util.c:386 > ovl_file_accessed+0x7e/0x370 fs/overlayfs/file.c:307 > backing_file_mmap+0x1f8/0x260 fs/backing-file.c:345 > ovl_mmap+0x1c9/0x220 fs/overlayfs/file.c:487 > call_mmap include/linux/fs.h:2183 [inline] > mmap_file mm/internal.h:124 [inline] > __mmap_new_file_vma mm/vma.c:2291 [inline] > __mmap_new_vma mm/vma.c:2355 [inline] > __mmap_region+0x2204/0x2cd0 mm/vma.c:2456 > mmap_region+0x1d0/0x2c0 mm/mmap.c:1347 > do_mmap+0x8f0/0x1000 mm/mmap.c:496 > vm_mmap_pgoff+0x214/0x430 mm/util.c:580 > ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:542 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7fb229019739 > Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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 b8 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007fffdd8656a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 > RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007fb229019739 > RDX: 0000000000000000 RSI: 0000000000004000 RDI: 0000000020ffc000 > RBP: 00007fb22908d610 R08: 0000000000000005 R09: 0000000000000000 > R10: 0000000000000012 R11: 0000000000000246 R12: 0000000000000001 > R13: 00007fffdd865878 R14: 0000000000000001 R15: 0000000000000001 > </TASK> > > Allocated by task 5827: > kasan_save_stack mm/kasan/common.c:47 [inline] > kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 > unpoison_slab_object mm/kasan/common.c:319 [inline] > __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 > kasan_slab_alloc include/linux/kasan.h:250 [inline] > slab_post_alloc_hook mm/slub.c:4104 [inline] > slab_alloc_node mm/slub.c:4153 [inline] > kmem_cache_alloc_lru_noprof+0x1dd/0x390 mm/slub.c:4172 > nilfs_alloc_inode+0x2e/0x110 fs/nilfs2/super.c:158 > alloc_inode+0x65/0x1a0 fs/inode.c:336 > iget5_locked+0x4a/0xa0 fs/inode.c:1404 > nilfs_iget_locked fs/nilfs2/inode.c:535 [inline] > nilfs_iget+0x130/0x810 fs/nilfs2/inode.c:544 > nilfs_lookup+0x198/0x210 fs/nilfs2/namei.c:69 > __lookup_slow+0x28c/0x3f0 fs/namei.c:1791 > lookup_slow fs/namei.c:1808 [inline] > lookup_one_unlocked+0x1a4/0x290 fs/namei.c:2966 > ovl_lookup_positive_unlocked fs/overlayfs/namei.c:210 [inline] > ovl_lookup_single+0x200/0xbd0 fs/overlayfs/namei.c:240 > ovl_lookup_layer+0x417/0x510 fs/overlayfs/namei.c:333 > ovl_lookup+0xcf7/0x2a60 fs/overlayfs/namei.c:1124 > lookup_open fs/namei.c:3627 [inline] > open_last_lookups fs/namei.c:3748 [inline] > path_openat+0x11a7/0x3590 fs/namei.c:3984 > do_filp_open+0x27f/0x4e0 fs/namei.c:4014 > do_sys_openat2+0x13e/0x1d0 fs/open.c:1402 > do_sys_open fs/open.c:1417 [inline] > __do_sys_open fs/open.c:1425 [inline] > __se_sys_open fs/open.c:1421 [inline] > __x64_sys_open+0x225/0x270 fs/open.c:1421 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > The buggy address belongs to the object at ffff88807df93300 > which belongs to the cache nilfs2_inode_cache of size 1504 > The buggy address is located 0 bytes to the right of > allocated 1504-byte region [ffff88807df93300, ffff88807df938e0) > > The buggy address belongs to the physical page: > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7df90 > head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 > flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) > page_type: f5(slab) > raw: 00fff00000000040 ffff88801f711140 dead000000000122 0000000000000000 > raw: 0000000000000000 0000000080140014 00000001f5000000 0000000000000000 > head: 00fff00000000040 ffff88801f711140 dead000000000122 0000000000000000 > head: 0000000000000000 0000000080140014 00000001f5000000 0000000000000000 > head: 00fff00000000003 ffffea0001f7e401 ffffffffffffffff 0000000000000000 > head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > page_owner tracks the page as allocated > page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 5827, tgid 5827 (syz-executor150), ts 58768101635, free_ts 15530782696 > set_page_owner include/linux/page_owner.h:32 [inline] > post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 > prep_new_page mm/page_alloc.c:1564 [inline] > get_page_from_freelist+0x3725/0x3870 mm/page_alloc.c:3510 > __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4787 > alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 > alloc_slab_page+0x6a/0x140 mm/slub.c:2408 > allocate_slab+0x5a/0x2f0 mm/slub.c:2574 > new_slab mm/slub.c:2627 [inline] > ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3815 > __slab_alloc+0x58/0xa0 mm/slub.c:3905 > __slab_alloc_node mm/slub.c:3980 [inline] > slab_alloc_node mm/slub.c:4141 [inline] > kmem_cache_alloc_lru_noprof+0x26c/0x390 mm/slub.c:4172 > nilfs_alloc_inode+0x2e/0x110 fs/nilfs2/super.c:158 > alloc_inode+0x65/0x1a0 fs/inode.c:336 > iget5_locked+0x4a/0xa0 fs/inode.c:1404 > nilfs_iget_locked+0x113/0x160 fs/nilfs2/inode.c:535 > nilfs_dat_read+0xc3/0x320 fs/nilfs2/dat.c:511 > nilfs_load_super_root fs/nilfs2/the_nilfs.c:118 [inline] > load_nilfs+0x579/0x1090 fs/nilfs2/the_nilfs.c:299 > nilfs_fill_super+0x31e/0x720 fs/nilfs2/super.c:1067 > page last free pid 1 tgid 1 stack trace: > reset_page_owner include/linux/page_owner.h:25 [inline] > free_pages_prepare mm/page_alloc.c:1127 [inline] > free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2693 > free_contig_range+0x152/0x550 mm/page_alloc.c:6666 > destroy_args+0x92/0x910 mm/debug_vm_pgtable.c:1017 > debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397 > do_one_initcall+0x248/0x880 init/main.c:1266 > do_initcall_level+0x157/0x210 init/main.c:1328 > do_initcalls+0x3f/0x80 init/main.c:1344 > kernel_init_freeable+0x435/0x5d0 init/main.c:1577 > kernel_init+0x1d/0x2b0 init/main.c:1466 > ret_from_fork+0x4b/0x80 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: > ffff88807df93780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffff88807df93800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > >ffff88807df93880: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc > ^ > ffff88807df93900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff88807df93980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ================================================================== > > #syz test: https://github.com/amir73il/linux ovl-fixes
