general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 5895 Comm: syz-executor.0 Not tainted 5.11.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:dma_unmap_sgtable include/linux/dma-mapping.h:345 [inline] RIP: 0010:put_sg_table drivers/dma-buf/udmabuf.c:80 [inline] RIP: 0010:release_udmabuf+0xc5/0x3e0 drivers/dma-buf/udmabuf.c:105 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 0c 03 00 00 48 8d 7d 0c 4c 8b 6b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ee RSP: 0018:ffffc9000183fde8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffffffff8b226220 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff888ae7e0 RDI: 0000000000000000 RBP: fffffffffffffff4 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff1860f99 R11: 0000000000000001 R12: ffff888021ecac80 R13: ffff88801b5ae000 R14: ffff88802bced858 R15: ffff88802bced780 FS: 0000555555d1a400(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f13acb620f0 CR3: 000000001497c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dma_buf_release+0x121/0x220 drivers/dma-buf/dma-buf.c:77 __dentry_kill+0x371/0x550 fs/dcache.c:584 __fput+0x2d3/0x870 fs/file_table.c:293 task_work_run+0xc0/0x160 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f13acb7aebb Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffdb17738c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007f13acb7aebb RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000006 RBP: 00007f13accdc980 R08: 0000000000000000 R09: 00007ffdb17f5090 R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000118e3 R13: 00007ffdb17739c0 R14: 00007ffdb17739e0 R15: 0000000000000032 Modules linked in: ---[ end trace 30c0bc64333b133a ]--- RIP: 0010:dma_unmap_sgtable include/linux/dma-mapping.h:345 [inline] RIP: 0010:put_sg_table drivers/dma-buf/udmabuf.c:80 [inline] RIP: 0010:release_udmabuf+0xc5/0x3e0 drivers/dma-buf/udmabuf.c:105 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 0c 03 00 00 48 8d 7d 0c 4c 8b 6b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ee RSP: 0018:ffffc9000183fde8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffffffff8b226220 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff888ae7e0 RDI: 0000000000000000 RBP: fffffffffffffff4 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff1860f99 R11: 0000000000000001 R12: ffff888021ecac80 R13: ffff88801b5ae000 R14: ffff88802bced858 R15: ffff88802bced780 FS: 0000555555d1a400(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f13acb620f0 CR3: 000000001497c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 89 fa mov %rdi,%rdx 3: 48 c1 ea 03 shr $0x3,%rdx 7: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) b: 0f 85 0c 03 00 00 jne 0x31d 11: 48 8d 7d 0c lea 0xc(%rbp),%rdi 15: 4c 8b 6b 30 mov 0x30(%rbx),%r13 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction 2e: 48 89 f8 mov %rdi,%rax 31: 83 e0 07 and $0x7,%eax 34: 83 c0 03 add $0x3,%eax 37: 38 d0 cmp %dl,%al 39: 7c 08 jl 0x43 3b: 84 d2 test %dl,%dl 3d: 0f .byte 0xf 3e: 85 ee test %ebp,%esi