Hello, syzbot found the following issue on: HEAD commit: 6dc544b66971 Add linux-next specific files for 20240528 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1590bec8980000 kernel config: https://syzkaller.appspot.com/x/.config?x=6a363b35598e573d dashboard link: https://syzkaller.appspot.com/bug?extid=40c7dad27267f61839d4 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/334699ab67f8/disk-6dc544b6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/4ca32b2218ce/vmlinux-6dc544b6.xz kernel image: https://storage.googleapis.com/syzbot-assets/400bc5f019b3/bzImage-6dc544b6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+40c7dad27267f61839d4@xxxxxxxxxxxxxxxxxxxxxxxxx Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 7202 Comm: syz-executor.4 Not tainted 6.10.0-rc1-next-20240528-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:PageTail include/linux/page-flags.h:284 [inline] RIP: 0010:const_folio_flags include/linux/page-flags.h:312 [inline] RIP: 0010:folio_test_head include/linux/page-flags.h:837 [inline] RIP: 0010:folio_test_large include/linux/page-flags.h:858 [inline] RIP: 0010:folio_nr_pages include/linux/mm.h:2076 [inline] RIP: 0010:udmabuf_create+0xa54/0x11c0 drivers/dma-buf/udmabuf.c:376 Code: 01 00 00 48 8b 44 24 70 42 80 3c 28 00 48 8b 5c 24 68 74 08 48 89 df e8 fa d5 ee fb 4c 8b 3b 49 8d 5f 08 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 dd d5 ee fb 48 8b 1b 48 89 de 48 RSP: 0018:ffffc9000cfcfbe0 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000008 RCX: dffffc0000000000 RDX: ffffc90009011000 RSI: 0000000000000cc5 RDI: 0000000000000cc6 RBP: ffffc9000cfcfd70 R08: ffffffff8fad856f R09: 1ffffffff1f5b0ad R10: dffffc0000000000 R11: fffffbfff1f5b0ae R12: 0000000000000001 R13: dffffc0000000000 R14: ffff88801bf793a8 R15: 0000000000000000 FS: 00007fb83bd9f6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32f21000 CR3: 000000002e5d8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> udmabuf_ioctl_create_list drivers/dma-buf/udmabuf.c:439 [inline] udmabuf_ioctl+0x3b2/0x4f0 drivers/dma-buf/udmabuf.c:454 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 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: 0033:0x7fb83b07cee9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb83bd9f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb83b1b3f80 RCX: 00007fb83b07cee9 RDX: 00000000200000c0 RSI: 0000000040087543 RDI: 0000000000000003 RBP: 00007fb83b0c947f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fb83b1b3f80 R15: 00007ffd6ccc32c8 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:PageTail include/linux/page-flags.h:284 [inline] RIP: 0010:const_folio_flags include/linux/page-flags.h:312 [inline] RIP: 0010:folio_test_head include/linux/page-flags.h:837 [inline] RIP: 0010:folio_test_large include/linux/page-flags.h:858 [inline] RIP: 0010:folio_nr_pages include/linux/mm.h:2076 [inline] RIP: 0010:udmabuf_create+0xa54/0x11c0 drivers/dma-buf/udmabuf.c:376 Code: 01 00 00 48 8b 44 24 70 42 80 3c 28 00 48 8b 5c 24 68 74 08 48 89 df e8 fa d5 ee fb 4c 8b 3b 49 8d 5f 08 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 dd d5 ee fb 48 8b 1b 48 89 de 48 RSP: 0018:ffffc9000cfcfbe0 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000008 RCX: dffffc0000000000 RDX: ffffc90009011000 RSI: 0000000000000cc5 RDI: 0000000000000cc6 RBP: ffffc9000cfcfd70 R08: ffffffff8fad856f R09: 1ffffffff1f5b0ad R10: dffffc0000000000 R11: fffffbfff1f5b0ae R12: 0000000000000001 R13: dffffc0000000000 R14: ffff88801bf793a8 R15: 0000000000000000 FS: 00007fb83bd9f6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32f21000 CR3: 000000002e5d8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 01 00 add %eax,(%rax) 2: 00 48 8b add %cl,-0x75(%rax) 5: 44 24 70 rex.R and $0x70,%al 8: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) d: 48 8b 5c 24 68 mov 0x68(%rsp),%rbx 12: 74 08 je 0x1c 14: 48 89 df mov %rbx,%rdi 17: e8 fa d5 ee fb call 0xfbeed616 1c: 4c 8b 3b mov (%rbx),%r15 1f: 49 8d 5f 08 lea 0x8(%r15),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 df mov %rbx,%rdi 34: e8 dd d5 ee fb call 0xfbeed616 39: 48 8b 1b mov (%rbx),%rbx 3c: 48 89 de mov %rbx,%rsi 3f: 48 rex.W --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title 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
