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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 507DC1C0005 X-Spam-Status: No, score=-8.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_PASS,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Stat-Signature: zd5pyfgwdaacifoerzxqktptnrj1szak X-HE-Tag: 1793557530-183917 X-HE-Meta: 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 OpiZDWZT 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 qAuMS+GD d5l8mKsf1i1hq0XY1pmAXdg4dxmrk4ZvB5c1YRzCZquSlvXS/Oz4WLUrE4ewTBUcSzGQhOOwSNbyWA3NpJJMtw9vt3U7VIUrOuBvAOfdKp+CLsSJkCfW4bVPMdqojcbi/ketFdipIyMSSacKY/zEZx/DtafyNyVwD4UH9zhUsNJ/D1mkyvIl5Ew1v/yPRfkCqG9lWO1ghNs= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Hello, syzbot found the following issue on: HEAD commit: 36aad21d50d1 Merge tag 'ksmbd-for-7.4-rc1-part2' of git://.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git console output: https://syzkaller.appspot.com/x/log.txt?x=12b81cb1580000 kernel config: https://syzkaller.appspot.com/x/.config?x=bd712e5dbce1d1a0 dashboard link: https://syzkaller.appspot.com/bug?extid=10e72ea5747737bcd2ad compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: i386 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12a58f95580000 AI-generated root cause summary: In validate_mm() (mm/vma.c), struct anon_vma *anon_vma = vma->anon_vma caches the anon_vma pointer at the beginning of the VMA iteration loop. In vms_complete_munmap_vmas(), mm->mmap_lock is downgraded to a read lock before validate_mm() is called, allowing a concurrent page fault on another thread to populate vma->anon_vma via __anon_vma_prepare(). When this race occurs, vma_has_anon_rmap(vma) evaluates to true by re-reading vma->anon_vma, but anon_vma_lock_read(anon_vma) is invoked with the stale NULL local variable, resulting in an unhandled NULL-pointer dereference and kernel crash. full analysis: https://syzkaller.appspot.com/x/ai_root_cause?x=10e72ea5747737bcd2ad IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+10e72ea5747737bcd2ad@syzkaller.appspotmail.com Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 UID: 0 PID: 6142 Comm: syz-executor263 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:anon_vma_lock_read mm/internal.h:315 [inline] RIP: 0010:validate_mm+0x3d4/0x780 mm/vma.c:707 Code: d2 e0 98 ff 48 89 df e8 5a 10 f1 ff c6 05 db a8 dd 0f 01 90 0f 0b 90 e9 04 fd ff ff e8 b5 e0 98 ff 48 8b 44 24 08 48 c1 e8 03 <80> 3c 28 00 0f 85 25 03 00 00 48 8b 44 24 08 4c 8d 63 30 48 8b 00 RSP: 0018:ffffc900040d7870 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88806b186000 RCX: 0000000000000000 RDX: ffff888000794b00 RSI: ffffffff8274c56b RDI: 0000000000000005 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88806b186083 R11: 0000000000000001 R12: ffff88806b186010 R13: ffff88806b186040 R14: 0000000000000001 R15: 000000000000003d FS: 0000000000000000(0000) GS:ffff888095281000(0063) knlGS:000000005727b3c0 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f7f72000 CR3: 000000004e463000 CR4: 0000000000352ef0 Call Trace: vms_complete_munmap_vmas+0x83b/0xdf0 mm/vma.c:1437 do_vmi_align_munmap+0x44f/0x5f0 mm/vma.c:1677 do_vmi_munmap+0x1f8/0x410 mm/vma.c:1725 __vm_munmap+0x196/0x3c0 mm/vma.c:3562 __do_sys_munmap mm/mmap.c:1094 [inline] __se_sys_munmap mm/mmap.c:1091 [inline] __ia32_sys_munmap+0x57/0x80 mm/mmap.c:1091 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x14b/0x8c0 arch/x86/entry/syscall_32.c:282 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:307 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7eaafbc Code: d2 74 05 c1 e8 0c 89 02 8b 5d fc 31 c0 c9 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 2e 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 58 b8 RSP: 002b:00000000ff8ab10c EFLAGS: 00000296 ORIG_RAX: 000000000000005b RAX: ffffffffffffffda RBX: 0000000020088000 RCX: 0000000000001000 RDX: 00000000f7f70ff4 RSI: 00000000000000fb RDI: 0000000000000040 RBP: 00000000ff8ab168 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:anon_vma_lock_read mm/internal.h:315 [inline] RIP: 0010:validate_mm+0x3d4/0x780 mm/vma.c:707 Code: d2 e0 98 ff 48 89 df e8 5a 10 f1 ff c6 05 db a8 dd 0f 01 90 0f 0b 90 e9 04 fd ff ff e8 b5 e0 98 ff 48 8b 44 24 08 48 c1 e8 03 <80> 3c 28 00 0f 85 25 03 00 00 48 8b 44 24 08 4c 8d 63 30 48 8b 00 RSP: 0018:ffffc900040d7870 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88806b186000 RCX: 0000000000000000 RDX: ffff888000794b00 RSI: ffffffff8274c56b RDI: 0000000000000005 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88806b186083 R11: 0000000000000001 R12: ffff88806b186010 R13: ffff88806b186040 R14: 0000000000000001 R15: 000000000000003d FS: 0000000000000000(0000) GS:ffff888095281000(0063) knlGS:000000005727b3c0 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f7f72000 CR3: 000000004e463000 CR4: 0000000000352ef0 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 48 89 df mov %rbx,%rdi 3: e8 5a 10 f1 ff call 0xfff11062 8: c6 05 db a8 dd 0f 01 movb $0x1,0xfdda8db(%rip) # 0xfdda8ea f: 90 nop 10: 0f 0b ud2 12: 90 nop 13: e9 04 fd ff ff jmp 0xfffffd1c 18: e8 b5 e0 98 ff call 0xff98e0d2 1d: 48 8b 44 24 08 mov 0x8(%rsp),%rax 22: 48 c1 e8 03 shr $0x3,%rax * 26: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) <-- trapping instruction 2a: 0f 85 25 03 00 00 jne 0x355 30: 48 8b 44 24 08 mov 0x8(%rsp),%rax 35: 4c 8d 63 30 lea 0x30(%rbx),%r12 39: 48 8b 00 mov (%rax),%rax --- 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@googlegroups.com. 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