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KASAN: slab-out-of-bounds Read in generic_perform_write

Status: upstream: reported C repro on 2023/09/17 14:11
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+00d2a588c9e933bd551c@syzkaller.appspotmail.com
First crash: 607d, last: 1d11h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/05/09 upstream (ToT) 448b3fe5a0ea C [report] KASAN: slab-out-of-bounds Read in generic_perform_write
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in generic_perform_write hfs mm C inconclusive done 10473 44d 600d 0/28 upstream: reported C repro on 2023/09/24 07:49
linux-6.1 KASAN: use-after-free Read in generic_perform_write origin:lts-only C unreliable 30 24d 613d 0/3 upstream: reported C repro on 2023/09/12 02:51
linux-4.14 KASAN: use-after-free Read in generic_perform_write (2) hfsplus jfs C error 20 841d 1259d 0/1 upstream: reported C repro on 2021/12/05 01:05
linux-4.19 KASAN: use-after-free Read in generic_perform_write hfsplus jfs C error 68 804d 1695d 0/1 upstream: reported C repro on 2020/09/24 08:55
linux-4.14 KASAN: use-after-free Read in generic_perform_write 11 1464d 1693d 0/1 auto-closed as invalid on 2021/09/11 00:48
upstream KASAN: use-after-free Read in generic_perform_write fs mm C error 73 1431d 2493d 0/28 auto-obsoleted due to no activity on 2023/04/14 08:17
▶ ▼ Last patch testing requests (7)
Created Duration User Patch Repo Result
2025/04/05 12:32 12m retest repro linux-5.15.y report log
2025/02/17 17:29 16m retest repro linux-5.15.y OK log
2025/02/17 17:29 19m retest repro linux-5.15.y OK log
2025/02/17 17:29 20m retest repro linux-5.15.y OK log
2025/02/17 17:29 20m retest repro linux-5.15.y OK log
2025/02/17 17:29 19m retest repro linux-5.15.y OK log
2025/01/24 08:26 15m retest repro linux-5.15.y OK log

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in copy_page_from_iter_atomic+0x8e3/0x1230 lib/iov_iter.c:978
Read of size 1024 at addr ffff88807abfec00 by task kworker/u4:4/1237

CPU: 0 PID: 1237 Comm: kworker/u4:4 Not tainted 5.15.158-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: loop0 loop_rootcg_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 kasan_check_range+0x27e/0x290 mm/kasan/generic.c:189
 memcpy+0x25/0x60 mm/kasan/shadow.c:65
 copy_page_from_iter_atomic+0x8e3/0x1230 lib/iov_iter.c:978
 generic_perform_write+0x33a/0x5b0 mm/filemap.c:3793
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
 do_iter_readv_writev+0x594/0x7a0
 do_iter_write+0x1ea/0x760 fs/read_write.c:855
 lo_write_bvec+0x297/0x740 drivers/block/loop.c:316
 lo_write_simple drivers/block/loop.c:338 [inline]
 do_req_filebacked drivers/block/loop.c:656 [inline]
 loop_handle_cmd drivers/block/loop.c:2234 [inline]
 loop_process_work+0x2309/0x2af0 drivers/block/loop.c:2274
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>

Allocated by task 3500:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 __kmalloc+0x168/0x300 mm/slub.c:4407
 kmalloc include/linux/slab.h:596 [inline]
 hfsplus_read_wrapper+0x4e3/0x13b0 fs/hfsplus/wrapper.c:180
 hfsplus_fill_super+0x38a/0x1c90 fs/hfsplus/super.c:413
 mount_bdev+0x2c9/0x3f0 fs/super.c:1387
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1517
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88807abfec00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 0 bytes inside of
 512-byte region [ffff88807abfec00, ffff88807abfee00)
The buggy address belongs to the page:
page:ffffea0001eaff00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7abfc
head:ffffea0001eaff00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000a00000001 ffff888011c41c80
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2964, ts 13748145428, free_ts 11348326457
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc_trace+0x1a0/0x290 mm/slub.c:3245
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 kernfs_fop_open+0x3b5/0xbc0 fs/kernfs/file.c:628
 do_dentry_open+0x807/0xfb0 fs/open.c:826
 do_open fs/namei.c:3608 [inline]
 path_openat+0x2705/0x2f20 fs/namei.c:3742
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x500 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_contig_range+0x95/0xf0 mm/page_alloc.c:9342
 destroy_args+0xfe/0x980 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x40d/0x470 mm/debug_vm_pgtable.c:1331
 do_one_initcall+0x22b/0x7a0 init/main.c:1302
 do_initcall_level+0x157/0x210 init/main.c:1375
 do_initcalls+0x49/0x90 init/main.c:1391
 kernel_init_freeable+0x425/0x5c0 init/main.c:1615
 kernel_init+0x19/0x290 init/main.c:1506
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300

Memory state around the buggy address:
 ffff88807abfed00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807abfed80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807abfee00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807abfee80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807abfef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (41):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/09 19:50 linux-5.15.y 284087d4f7d5 05079661 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/10/27 06:42 linux-5.15.y 74cdd62cb470 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/09/19 23:13 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/09/19 23:13 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/09/08 10:00 linux-5.15.y 14e468424d3e 9750182a .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/06/03 05:26 linux-5.15.y c61bd26ae81a 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/05/02 17:37 linux-5.15.y 284087d4f7d5 3ba885bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/05/01 21:31 linux-5.15.y b925f60c6ee7 3ba885bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/04/04 18:35 linux-5.15.y 9465fef4ae35 0ee3535e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2023/10/09 19:44 linux-5.15.y 1edcec18cfb7 3c53c7d9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in generic_perform_write
2024/12/13 00:25 linux-5.15.y 0a51d2d4527b 530e80f8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/12/09 19:50 linux-5.15.y 0a51d2d4527b 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/11/23 20:56 linux-5.15.y 0a51d2d4527b 68da6d95 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/11/20 10:30 linux-5.15.y 0a51d2d4527b 7d02db5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/10/21 06:36 linux-5.15.y 584a40a22cb9 cd6fc0a3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/10/06 14:20 linux-5.15.y 3a5928702e71 d7906eff .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/06/06 13:20 linux-5.15.y c61bd26ae81a 121701b6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/06/05 10:38 linux-5.15.y c61bd26ae81a e1e2c66e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/05/22 21:40 linux-5.15.y 83655231580b 4d098039 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/03/23 00:42 linux-5.15.y b95c01af2113 4b6cdce6 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/03/15 20:20 linux-5.15.y b95c01af2113 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/03/12 10:22 linux-5.15.y 574362648507 6ee49f2e .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/02/25 05:06 linux-5.15.y 458ce51d0356 8d446f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/02/05 15:05 linux-5.15.y 6139f2a02fe0 e23e8c20 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/02/04 16:07 linux-5.15.y 6139f2a02fe0 a67b2c42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2024/02/02 02:21 linux-5.15.y 6139f2a02fe0 d61103fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2023/09/17 14:10 linux-5.15.y aff03380bda4 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: slab-out-of-bounds Read in generic_perform_write
2025/05/15 19:21 linux-5.15.y 3b8db0e4f263 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2025/04/07 12:28 linux-5.15.y 0c935c049b5c 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2025/02/28 20:58 linux-5.15.y c16c81c81336 67cf5345 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2025/01/09 19:40 linux-5.15.y 4735586da88e 9220929f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2024/11/25 03:21 linux-5.15.y 0a51d2d4527b 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2024/10/14 01:14 linux-5.15.y 3a5928702e71 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2024/07/19 20:53 linux-5.15.y 7c6d66f0266f 890ce4f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2024/04/24 03:19 linux-5.15.y c52b9710c83d 21339d7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2024/03/20 15:24 linux-5.15.y b95c01af2113 5b7d42ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2023/12/22 21:46 linux-5.15.y 1d146b1875fc fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in generic_perform_write
2025/04/25 18:31 linux-5.15.y f7347f400572 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in generic_perform_write
2024/10/31 06:50 linux-5.15.y 74cdd62cb470 96eb609f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in generic_perform_write
2024/09/10 19:40 linux-5.15.y 14e468424d3e 86aa7bd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in generic_perform_write
2023/12/29 11:46 linux-5.15.y d93fa2c78854 fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in generic_perform_write
* Struck through repros no longer work on HEAD.