syzbot


KMSAN: uninit-value in __exfat_get_dentry_set

Status: upstream: reported C repro on 2024/10/05 14:32
Subsystems: exfat
[Documentation on labels]
Reported-by: syzbot+01218003be74b5e1213a@syzkaller.appspotmail.com
Fix commit: 02dffe9ab092 exfat: fix uninit-value in __exfat_get_dentry_set
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu2-arm32]
First crash: 177d, last: 119d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH v1 2/2] exfat: fix uninit-value in __exfat_get_dentry_set 1 (1) 2024/10/30 07:47
[syzbot] [exfat?] KMSAN: uninit-value in __exfat_get_dentry_set 8 (22) 2024/10/29 09:28
Last patch testing requests (18)
Created Duration User Patch Repo Result
2024/10/29 04:17 1h10m linkinjeon@kernel.org patch upstream OK log
2024/10/19 04:01 25m linkinjeon@kernel.org patch upstream report log
2024/10/17 09:49 21m yuezhang.mo@sony.com patch upstream report log
2024/10/17 03:33 31m yuezhang.mo@sony.com patch upstream OK log
2024/10/17 02:20 33m yuezhang.mo@sony.com patch upstream OK log
2024/10/17 00:22 29m retest repro upstream report log
2024/10/17 00:22 24m retest repro upstream report log
2024/10/17 00:22 21m retest repro upstream report log
2024/10/17 00:22 22m retest repro upstream report log
2024/10/17 00:22 25m retest repro upstream report log
2024/10/14 09:00 1h28m yuezhang.mo@sony.com patch upstream report log
2024/10/14 06:40 50m yuezhang.mo@sony.com patch upstream report log
2024/10/12 15:39 23m surajsonawane0215@gmail.com patch upstream report log
2024/10/12 07:48 22m surajsonawane0215@gmail.com patch upstream report log
2024/10/11 13:04 22m sarvesh20123@gmail.com patch upstream report log
2024/10/11 12:33 6m sarvesh20123@gmail.com patch upstream error
2024/10/10 14:01 24m niharchaithanya@gmail.com patch upstream report log
2024/10/10 12:39 21m niharchaithanya@gmail.com patch upstream report log

Sample crash report:
exFAT-fs (loop0): failed to load upcase table (idx : 0x00010000, chksum : 0x726052d3, utbl_chksum : 0xe619d30d)
=====================================================
BUG: KMSAN: uninit-value in __exfat_get_dentry_set+0x10ca/0x14d0 fs/exfat/dir.c:804
 __exfat_get_dentry_set+0x10ca/0x14d0 fs/exfat/dir.c:804
 exfat_get_dentry_set+0x58/0xec0 fs/exfat/dir.c:859
 __exfat_write_inode+0x3c1/0xe30 fs/exfat/inode.c:46
 __exfat_truncate+0x7f3/0xbb0 fs/exfat/file.c:211
 exfat_truncate+0xee/0x2a0 fs/exfat/file.c:257
 exfat_write_failed fs/exfat/inode.c:421 [inline]
 exfat_direct_IO+0x5a3/0x900 fs/exfat/inode.c:485
 generic_file_direct_write+0x275/0x6a0 mm/filemap.c:3977
 __generic_file_write_iter+0x242/0x460 mm/filemap.c:4141
 exfat_file_write_iter+0x894/0xfb0 fs/exfat/file.c:598
 do_iter_readv_writev+0x88a/0xa30
 vfs_writev+0x56a/0x14f0 fs/read_write.c:1064
 do_pwritev fs/read_write.c:1165 [inline]
 __do_sys_pwritev2 fs/read_write.c:1224 [inline]
 __se_sys_pwritev2+0x280/0x470 fs/read_write.c:1215
 __x64_sys_pwritev2+0x11f/0x1a0 fs/read_write.c:1215
 x64_sys_call+0x2edb/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:329
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 memcpy_to_iter lib/iov_iter.c:65 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 _copy_to_iter+0xe53/0x2b30 lib/iov_iter.c:185
 copy_page_to_iter+0x419/0x880 lib/iov_iter.c:362
 shmem_file_read_iter+0xa09/0x12b0 mm/shmem.c:3167
 do_iter_readv_writev+0x88a/0xa30
 vfs_iter_read+0x278/0x760 fs/read_write.c:923
 lo_read_simple drivers/block/loop.c:283 [inline]
 do_req_filebacked drivers/block/loop.c:516 [inline]
 loop_handle_cmd drivers/block/loop.c:1910 [inline]
 loop_process_work+0x20fc/0x3750 drivers/block/loop.c:1945
 loop_rootcg_workfn+0x2b/0x40 drivers/block/loop.c:1976
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_page_from_iter_atomic+0x12b7/0x3100 lib/iov_iter.c:481
 copy_folio_from_iter_atomic include/linux/uio.h:201 [inline]
 generic_perform_write+0x8d1/0x1080 mm/filemap.c:4066
 shmem_file_write_iter+0x2ba/0x2f0 mm/shmem.c:3221
 do_iter_readv_writev+0x88a/0xa30
 vfs_iter_write+0x44d/0xd40 fs/read_write.c:988
 lo_write_bvec drivers/block/loop.c:243 [inline]
 lo_write_simple drivers/block/loop.c:264 [inline]
 do_req_filebacked drivers/block/loop.c:511 [inline]
 loop_handle_cmd drivers/block/loop.c:1910 [inline]
 loop_process_work+0x15e6/0x3750 drivers/block/loop.c:1945
 loop_rootcg_workfn+0x2b/0x40 drivers/block/loop.c:1976
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 __alloc_pages_noprof+0x9d6/0xe70 mm/page_alloc.c:4756
 alloc_pages_mpol_noprof+0x299/0x990 mm/mempolicy.c:2265
 alloc_pages_noprof mm/mempolicy.c:2345 [inline]
 folio_alloc_noprof+0x1db/0x310 mm/mempolicy.c:2352
 filemap_alloc_folio_noprof+0xa6/0x440 mm/filemap.c:1010
 __filemap_get_folio+0xac4/0x1550 mm/filemap.c:1952
 block_write_begin+0x6e/0x2b0 fs/buffer.c:2226
 exfat_write_begin+0xfb/0x400 fs/exfat/inode.c:434
 exfat_extend_valid_size fs/exfat/file.c:553 [inline]
 exfat_file_write_iter+0x474/0xfb0 fs/exfat/file.c:588
 do_iter_readv_writev+0x88a/0xa30
 vfs_writev+0x56a/0x14f0 fs/read_write.c:1064
 do_pwritev fs/read_write.c:1165 [inline]
 __do_sys_pwritev2 fs/read_write.c:1224 [inline]
 __se_sys_pwritev2+0x280/0x470 fs/read_write.c:1215
 __x64_sys_pwritev2+0x11f/0x1a0 fs/read_write.c:1215
 x64_sys_call+0x2edb/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:329
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 5188 Comm: syz-executor221 Not tainted 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
=====================================================

Crashes (14):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/02 09:36 upstream e32cde8d2bd7 ea2b66a6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/02 08:01 upstream e32cde8d2bd7 ea2b66a6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/02 06:20 upstream e32cde8d2bd7 ea2b66a6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/02 04:47 upstream e32cde8d2bd7 ea2b66a6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/02 03:14 upstream e32cde8d2bd7 ea2b66a6 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/11/28 19:56 upstream b86545e02e8c 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/11/13 06:41 upstream 3022e9d00ebe 62026c85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/11/02 16:56 upstream 11066801dd4b f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/27 08:23 upstream 850925a8133c 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/27 08:23 upstream 850925a8133c 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/27 08:23 upstream 850925a8133c 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/26 01:23 upstream b423f5a9a61f 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/01 14:27 upstream e32cde8d2bd7 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __exfat_get_dentry_set
2024/10/26 21:47 upstream 850925a8133c 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __exfat_get_dentry_set
* Struck through repros no longer work on HEAD.