#syz dup: WARNING: kmalloc bug in memslot_rmap_alloc On 18/10/21 08:42, syzbot wrote:
Hello, syzbot found the following issue on: HEAD commit: d999ade1cc86 Merge tag 'perf-tools-fixes-for-v5.15-2021-10.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=161ab644b00000 kernel config: https://syzkaller.appspot.com/x/.config?x=bab9d35f204746a7 dashboard link: https://syzkaller.appspot.com/bug?extid=d9c9b7cff3d4ec7a589e compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: i386 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11fcdc34b00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14785d34b00000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d9c9b7cff3d4ec7a589e@xxxxxxxxxxxxxxxxxxxxxxxxx L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 6533 at mm/util.c:597 kvmalloc_node+0x111/0x120 mm/util.c:597 Modules linked in: CPU: 0 PID: 6533 Comm: syz-executor711 Not tainted 5.15.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:kvmalloc_node+0x111/0x120 mm/util.c:597 Code: 01 00 00 00 4c 89 e7 e8 ad 18 0d 00 49 89 c5 e9 69 ff ff ff e8 60 91 d0 ff 41 89 ed 41 81 cd 00 20 01 00 eb 95 e8 4f 91 d0 ff <0f> 0b e9 4c ff ff ff 0f 1f 84 00 00 00 00 00 55 48 89 fd 53 e8 36 RSP: 0018:ffffc900011ef6e8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88807a7e8000 RSI: ffffffff81a646c1 RDI: 0000000000000003 RBP: 0000000000400dc0 R08: 000000007fffffff R09: ffff8880b9d32a0b R10: ffffffff81a6467e R11: 000000000000003f R12: 00000000e0000000 R13: 0000000000000000 R14: 00000000ffffffff R15: ffffc900011ef950 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0063) knlGS:0000000056d512c0 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000055ad809529a0 CR3: 000000001ae94000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kvmalloc include/linux/mm.h:805 [inline] kvmalloc_array include/linux/mm.h:823 [inline] kvcalloc include/linux/mm.h:828 [inline] kvm_page_track_create_memslot+0x50/0x110 arch/x86/kvm/mmu/page_track.c:39 kvm_alloc_memslot_metadata arch/x86/kvm/x86.c:11501 [inline] kvm_arch_prepare_memory_region+0x350/0x610 arch/x86/kvm/x86.c:11538 kvm_set_memslot+0x172/0x1a40 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1592 __kvm_set_memory_region+0xc1c/0x13d0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1755 kvm_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1776 [inline] kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1788 [inline] kvm_vm_ioctl+0x520/0x23d0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4363 kvm_vm_compat_ioctl+0x288/0x350 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4588 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:972 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7e67549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000ff89659c EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000004020ae46 RDX: 00000000200001c0 RSI: 00000000ff8965f0 RDI: 00000000f7f0a000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi --- 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. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
