Hello, syzbot found the following issue on: HEAD commit: 7b4b9bf203da Add linux-next specific files for 20250107 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=14246bc4580000 kernel config: https://syzkaller.appspot.com/x/.config?x=63fa2c9d5e12faef dashboard link: https://syzkaller.appspot.com/bug?extid=fcee6b76cf2e261c51a4 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=174f0a18580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=168aecb0580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/c179cc0c7a3c/disk-7b4b9bf2.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/fdea80f2ec16/vmlinux-7b4b9bf2.xz kernel image: https://storage.googleapis.com/syzbot-assets/a277fcaff608/bzImage-7b4b9bf2.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/a96fcb87dd70/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+fcee6b76cf2e261c51a4@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: global-out-of-bounds in number+0x3be/0xf40 lib/vsprintf.c:494 Read of size 1 at addr ffffffff8c5fc971 by task syz-executor351/5832 CPU: 0 UID: 0 PID: 5832 Comm: syz-executor351 Not tainted 6.13.0-rc6-next-20250107-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 number+0x3be/0xf40 lib/vsprintf.c:494 pointer+0x764/0x1210 lib/vsprintf.c:2484 vsnprintf+0x75a/0x1220 lib/vsprintf.c:2846 seq_vprintf fs/seq_file.c:391 [inline] seq_printf+0x172/0x270 fs/seq_file.c:406 show_partition+0x29f/0x3f0 block/genhd.c:905 seq_read_iter+0x969/0xd70 fs/seq_file.c:272 proc_reg_read_iter+0x1c2/0x290 fs/proc/inode.c:299 copy_splice_read+0x63a/0xb40 fs/splice.c:365 do_splice_read fs/splice.c:985 [inline] splice_direct_to_actor+0x4af/0xc80 fs/splice.c:1089 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1424 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1410 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: 0033:0x7f3fa8cf4c69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 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:00007ffd536a0078 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3fa8cf4c69 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 RBP: 00007f3fa8d685f0 R08: 000055558679c4c0 R09: 000055558679c4c0 R10: 000000000000023b R11: 0000000000000246 R12: 00007ffd536a00a0 R13: 00007ffd536a02c8 R14: 431bde82d7b634db R15: 00007f3fa8d3d03b </TASK> The buggy address belongs to the variable: hex_asc_upper+0x11/0x40 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xc5fc flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000002000 ffffea0000317f08 ffffea0000317f08 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner info is not present (never set?) Memory state around the buggy address: ffffffff8c5fc800: 00 03 f9 f9 02 f9 f9 f9 02 f9 f9 f9 00 02 f9 f9 ffffffff8c5fc880: 00 04 f9 f9 00 03 f9 f9 07 f9 f9 f9 00 00 04 f9 >ffffffff8c5fc900: f9 f9 f9 f9 00 00 01 f9 f9 f9 f9 f9 00 00 01 f9 ^ ffffffff8c5fc980: f9 f9 f9 f9 00 04 f9 f9 02 f9 f9 f9 01 f9 f9 f9 ffffffff8c5fca00: 00 f9 f9 f9 00 f9 f9 f9 00 04 f9 f9 00 06 f9 f9 ================================================================== --- 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. 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