syzbot has found a reproducer for the following issue on: HEAD commit: cf72cbb39da8 Merge tag 'io_uring-7.3-20260828' of git://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16e7cc15580000 kernel config: https://syzkaller.appspot.com/x/.config?x=85bc5cc2fc7394d9 dashboard link: https://syzkaller.appspot.com/bug?extid=5ebeb3089ea6439c37be compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: i386 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=159ebd79580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=123d1d79580000
Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-cf72cbb3.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/755d053ff703/vmlinux-cf72cbb3.xz kernel image: https://storage.googleapis.com/syzbot-assets/0837738ba281/bzImage-cf72cbb3.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: [email protected] BUG: unable to handle page fault for address: ffffffffffffffdc #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD eb99067 P4D eb99067 PUD eb9b067 PMD 0 Oops: Oops: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 5921 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:strlen+0x30/0xa0 lib/string.c:402 Code: 00 00 00 00 00 fc ff df 55 48 89 fa 48 89 fd 53 48 c1 ea 03 48 83 ec 08 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 50 <80> 7d 00 00 74 3d 48 bb 00 00 00 00 00 fc ff df 48 89 e8 48 83 c0 RSP: 0018:ffffc90002eb7920 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffffffffffdc RCX: 0000000000000000 RDX: 0000000000000004 RSI: ffffffff82081bc1 RDI: ffffffffffffffdc RBP: ffffffffffffffdc R08: 0000000000000004 R09: 00000000000000a9 R10: 00000000000006c0 R11: 0000000000000001 R12: ffff888027be0e40 R13: 0000000000000007 R14: 00000000fffffff3 R15: ffffffffffffffdc FS: 0000000000000000(0000) GS:ffff888096967000(0063) knlGS:000000005783f480 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: ffffffffffffffdc CR3: 0000000055e55000 CR4: 0000000000352ef0 Call Trace: <TASK> __fortify_strlen include/linux/fortify-string.h:218 [inline] audit_log_untrustedstring+0x19/0x30 kernel/audit.c:2203 integrity_audit_message+0x366/0x4f0 security/integrity/integrity_audit.c:60 integrity_audit_msg+0x41/0x60 security/integrity/integrity_audit.c:32 validate_hash_algo security/integrity/ima/ima_appraise.c:752 [inline] ima_inode_setxattr+0x512/0x5f0 security/integrity/ima/ima_appraise.c:775 security_inode_setxattr+0x299/0x560 security/security.c:1940 __vfs_setxattr_locked+0xad/0x2b0 fs/xattr.c:309 vfs_setxattr+0x14a/0x390 fs/xattr.c:344 do_setxattr+0x145/0x180 fs/xattr.c:662 file_setxattr fs/xattr.c:672 [inline] file_setxattr+0x139/0x1b0 fs/xattr.c:666 path_setxattrat+0x335/0x3b0 fs/xattr.c:732 __do_sys_fsetxattr fs/xattr.c:782 [inline] __se_sys_fsetxattr fs/xattr.c:779 [inline] __ia32_sys_fsetxattr+0xc4/0x140 fs/xattr.c:779 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fb7fec Code: Unable to access opcode bytes at 0xf7fb7fc2. RSP: 002b:00000000fffd97bc EFLAGS: 00000296 ORIG_RAX: 00000000000000e4 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000080 RDX: 0000000080001080 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: CR2: ffffffffffffffdc ---[ end trace 0000000000000000 ]--- RIP: 0010:strlen+0x30/0xa0 lib/string.c:402 Code: 00 00 00 00 00 fc ff df 55 48 89 fa 48 89 fd 53 48 c1 ea 03 48 83 ec 08 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 50 <80> 7d 00 00 74 3d 48 bb 00 00 00 00 00 fc ff df 48 89 e8 48 83 c0 RSP: 0018:ffffc90002eb7920 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffffffffffdc RCX: 0000000000000000 RDX: 0000000000000004 RSI: ffffffff82081bc1 RDI: ffffffffffffffdc RBP: ffffffffffffffdc R08: 0000000000000004 R09: 00000000000000a9 R10: 00000000000006c0 R11: 0000000000000001 R12: ffff888027be0e40 R13: 0000000000000007 R14: 00000000fffffff3 R15: ffffffffffffffdc FS: 0000000000000000(0000) GS:ffff888096967000(0063) knlGS:000000005783f480 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f7fb8000 CR3: 0000000055e55000 CR4: 0000000000352ef0 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 4: 00 fc add %bh,%ah 6: ff lcall (bad) 7: df 55 48 fists 0x48(%rbp) a: 89 fa mov %edi,%edx c: 48 89 fd mov %rdi,%rbp f: 53 push %rbx 10: 48 c1 ea 03 shr $0x3,%rdx 14: 48 83 ec 08 sub $0x8,%rsp 18: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 1c: 48 89 fa mov %rdi,%rdx 1f: 83 e2 07 and $0x7,%edx 22: 38 d0 cmp %dl,%al 24: 7f 04 jg 0x2a 26: 84 c0 test %al,%al 28: 75 50 jne 0x7a * 2a: 80 7d 00 00 cmpb $0x0,0x0(%rbp) <-- trapping instruction 2e: 74 3d je 0x6d 30: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 37: fc ff df 3a: 48 89 e8 mov %rbp,%rax 3d: 48 rex.W 3e: 83 .byte 0x83 3f: c0 .byte 0xc0 --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.
