Hello, syzbot found the following issue on: HEAD commit: 382d4cd18475 lib/clz_ctz.c: Fix __clzdi2() and __ctzdi2() .. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15979833a80000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b32f62c755c3a9c dashboard link: https://syzkaller.appspot.com/bug?extid=1f2eb3e8cd123ffce499 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/57260ac283ce/disk-382d4cd1.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8be20b71d903/vmlinux-382d4cd1.xz kernel image: https://storage.googleapis.com/syzbot-assets/518fe2320c33/bzImage-382d4cd1.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1f2eb3e8cd123ffce499@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================================ UBSAN: array-index-out-of-bounds in lib/zstd/common/fse_decompress.c:345:30 index 33 is out of range for type 'FSE_DTable[1]' (aka 'unsigned int[1]') CPU: 0 PID: 2895 Comm: kworker/u4:7 Not tainted 6.5.0-rc7-syzkaller-00164-g382d4cd18475 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: btrfs-endio btrfs_end_bio_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 ubsan_epilogue lib/ubsan.c:217 [inline] __ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348 FSE_decompress_wksp_body lib/zstd/common/fse_decompress.c:345 [inline] FSE_decompress_wksp_body_bmi2+0x2e8/0x3790 lib/zstd/common/fse_decompress.c:370 FSE_decompress_wksp_bmi2+0xc7/0x3670 lib/zstd/common/fse_decompress.c:378 HUF_readStats_body lib/zstd/common/entropy_common.c:289 [inline] HUF_readStats_body_bmi2+0xba/0x620 lib/zstd/common/entropy_common.c:340 HUF_readDTableX1_wksp_bmi2+0x161/0x2740 lib/zstd/decompress/huf_decompress.c:353 HUF_decompress1X1_DCtx_wksp_bmi2+0x4e/0xe0 lib/zstd/decompress/huf_decompress.c:1693 ZSTD_decodeLiteralsBlock+0x1009/0x1560 lib/zstd/decompress/zstd_decompress_block.c:195 ZSTD_decompressBlock_internal+0x106/0xacc0 lib/zstd/decompress/zstd_decompress_block.c:1995 ZSTD_decompressContinue+0x571/0x1690 lib/zstd/decompress/zstd_decompress.c:1184 ZSTD_decompressContinueStream lib/zstd/decompress/zstd_decompress.c:1855 [inline] ZSTD_decompressStream+0x208f/0x3080 lib/zstd/decompress/zstd_decompress.c:2036 zstd_decompress_bio+0x22b/0x570 fs/btrfs/zstd.c:573 compression_decompress_bio fs/btrfs/compression.c:131 [inline] btrfs_decompress_bio fs/btrfs/compression.c:930 [inline] end_compressed_bio_read+0x145/0x400 fs/btrfs/compression.c:178 btrfs_check_read_bio+0x138f/0x19b0 fs/btrfs/bio.c:324 process_one_work+0x92c/0x12c0 kernel/workqueue.c:2600 worker_thread+0xa63/0x1210 kernel/workqueue.c:2751 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 </TASK> ================================================================================ --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
