On 27 August 2026 02:22:17 BST, Paul Moore <[email protected]> wrote: >On Wed, Aug 26, 2026 at 9:06 PM Bradley Morgan <[email protected]> >wrote: >> On 27 August 2026 01:50:45 BST, syzbot >> <[email protected]> wrote: >> >Hello, >> > >> >syzbot found the following issue on: >> >> #syz set subsystems security: >> >> Note: here's my suggested fix, in security/ima_appraise.c >> >> path = dentry_path(dentry, pathbuf, PATH_MAX); >> +if (IS_ERR(path)) >> path = NULL; >> >> apparmor and tomoyo both IS_ERR check their dentry_path calls, ima >> is the only one that doesnt. NULL fname is already handled by the audit >> side > >Thanks for taking a look Bradley. Adding Mimi, Roberto, and the >linux-integrity list as the security/integrity/ima/ima_appraise.c file >is their domain. >
np man, do you want me to submit a patch for it? or nahhhh >> >HEAD commit: 66fb95a52111 Merge tag 'caps-pr-20260820' of >> >git://git.ker.. >> >git tree: upstream >> >console output: >https://syzkaller.appspot.com/x/log.txt?x=1560d549580000 >> >kernel config: >https://syzkaller.appspot.com/x/.config?x=b0978f5ed2905b98 >> >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 >> >syz repro: >https://syzkaller.appspot.com/x/repro.syz?x=16fb4625580000 >> > >> >Downloadable assets: >> >disk image: >> >>https://storage.googleapis.com/syzbot-assets/e7d9049723b0/disk-66fb95a5.raw.xz >> >vmlinux: >https://storage.googleapis.com/syzbot-assets/a04d6efe59a0/vmlinux-66fb95a5.xz >> >kernel image: >> >>https://storage.googleapis.com/syzbot-assets/81e3f2b9c049/bzImage-66fb95a5.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 eb97067 P4D eb97067 PUD eb99067 PMD 0 >> >Oops: Oops: 0000 [#1] SMP KASAN NOPTI >> >CPU: 0 UID: 0 PID: 5818 Comm: syz.0.17 Not tainted syzkaller #0 >PREEMPT(full) >> >Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >> >Google 07/16/2026 >> >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:ffffc90003d77940 EFLAGS: 00010246 >> >RAX: 0000000000000000 RBX: ffffffffffffffdc RCX: 0000000000000000 >> >RDX: 0000000000000004 RSI: ffffffff8207fb91 RDI: ffffffffffffffdc >> >RBP: ffffffffffffffdc R08: 0000000000000004 R09: 00000000000000b7 >> >R10: 00000000000006c0 R11: ffffffff8bc921d3 R12: ffff8880785a84c0 >> >R13: 0000000000000007 R14: 00000000fffffff3 R15: ffffffffffffffdc >> >FS: 000055555ec16500(0000) GS:ffff888123b86000(0000) >knlGS:0000000000000000 >> >CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> >CR2: ffffffffffffffdc CR3: 0000000075fb6000 CR4: 00000000003526f0 >> >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+0x2d0/0x560 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] >> > __x64_sys_fsetxattr+0xc5/0x140 fs/xattr.c:779 >> > do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] >> > do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 >> > entry_SYSCALL_64_after_hwframe+0x77/0x7f >> >RIP: 0033:0x7f506239e0d9 >> >Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48 >> >RSP: 002b:00007fff3373f938 EFLAGS: 00000246 ORIG_RAX: 00000000000000be >> >RAX: ffffffffffffffda RBX: 00007f5062625fa0 RCX: 00007f506239e0d9 >> >RDX: 0000200000000380 RSI: 0000200000000080 RDI: 0000000000000004 >> >RBP: 00007f5062435024 R08: 0000000000000000 R09: 0000000000000000 >> >R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 >> >R13: 00007f5062625fac R14: 00007f5062625fa0 R15: 00007f5062625fa0 >> > </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:ffffc90003d77940 EFLAGS: 00010246 >> >RAX: 0000000000000000 RBX: ffffffffffffffdc RCX: 0000000000000000 >> >RDX: 0000000000000004 RSI: ffffffff8207fb91 RDI: ffffffffffffffdc >> >RBP: ffffffffffffffdc R08: 0000000000000004 R09: 00000000000000b7 >> >R10: 00000000000006c0 R11: ffffffff8bc921d3 R12: ffff8880785a84c0 >> >R13: 0000000000000007 R14: 00000000fffffff3 R15: ffffffffffffffdc >> >FS: 000055555ec16500(0000) GS:ffff888123b86000(0000) >knlGS:0000000000000000 >> >CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> >CR2: ffffffffffffffdc CR3: 0000000075fb6000 CR4: 00000000003526f0 >> >---------------- >> >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 >> > >> > >> >--- >> >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 [email protected]. >> > >> >syzbot will keep track of this issue. See: >> >https://goo.gl/tpsmEJ#status for how to communicate with syzbot. >> > >> >If the report is already addressed, let syzbot know by replying with: >> >#syz fix: exact-commit-title >> > >> >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. >> > >> >If you want to overwrite report's subsystems, reply with: >> >#syz set subsystems: new-subsystem >> >(See the list of subsystem names on the web dashboard) >> > >> >If the report is a duplicate of another one, reply with: >> >#syz dup: exact-subject-of-another-report >> > >> >If you want to undo deduplication, reply with: >> >#syz undup >> > >> > >> >> --- Thanks! >> >https://lore.kernel.org/all/[email protected]/ > > > > --- Thanks! https://lore.kernel.org/all/[email protected]/
