8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 0000008d when read [0000008d] *pgd=85442003, *pmd=fc491003 Internal error: Oops: 207 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 13298 Comm: syz-executor.0 Not tainted 6.9.0-rc2-syzkaller #0 Hardware name: ARM-Versatile Express PC is at xdp_ok_fwd_dev include/linux/filter.h:1009 [inline] PC is at dev_map_generic_redirect+0x24/0x23c kernel/bpf/devmap.c:681 LR is at xdp_do_generic_redirect_map net/core/filter.c:4463 [inline] LR is at xdp_do_generic_redirect+0x1d8/0x4d4 net/core/filter.c:4520 pc : [<803f2e70>] lr : [<813e318c>] psr: 60000013 sp : dfa41d00 ip : dfa41d58 fp : dfa41d54 r10: 0000fdef r9 : 83641800 r8 : dfa43000 r7 : 00000001 r6 : 841bb400 r5 : 855c8a80 r4 : 824b3560 r3 : 00000000 r2 : dfa43000 r1 : 855c8a80 r0 : 841bb400 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85104f00 DAC: 00000000 Register r0 information: slab kmalloc-cg-64 start 841bb400 pointer offset 0 size 64 Register r1 information: slab skbuff_head_cache start 855c8a80 pointer offset 0 size 192 Register r2 information: 1-page vmalloc region starting at 0xdfa43000 allocated at bpf_prog_alloc_no_stats+0x38/0x1cc kernel/bpf/core.c:103 Register r3 information: NULL pointer Register r4 information: non-slab/vmalloc memory Register r5 information: slab skbuff_head_cache start 855c8a80 pointer offset 0 size 192 Register r6 information: slab kmalloc-cg-64 start 841bb400 pointer offset 0 size 64 Register r7 information: non-paged memory Register r8 information: 1-page vmalloc region starting at 0xdfa43000 allocated at bpf_prog_alloc_no_stats+0x38/0x1cc kernel/bpf/core.c:103 Register r9 information: slab task_struct start 83641800 pointer offset 0 size 3072 Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfa40000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Register r12 information: 2-page vmalloc region starting at 0xdfa40000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796 Process syz-executor.0 (pid: 13298, stack limit = 0xdfa40000) Stack: (0xdfa41d00 to 0xdfa42000) 1d00: 804a6614 8027b0a4 855c8a80 dfa41da4 854a0102 854afef1 dfa43000 0000000e 1d20: dfa41d3c dfa41d30 824b3560 824b3560 855c8a80 84c46000 dfa41da4 0000000e 1d40: 00000024 5b930000 dfa41d9c dfa41d58 813e318c 803f2e58 dfa41d9c dfa41d68 1d60: 0000aaaa 00000000 841bb400 dfa43000 dfa41db4 dfa41e40 00000004 0000000e 1d80: dfa43000 83641800 83404800 00000000 dfa41dec dfa41da0 813ae474 813e2fc0 1da0: dfa41ef0 854a0102 854afef1 854a0102 854a0000 85060400 00000000 00020000 1dc0: 00000000 d2f4c1d4 84c46660 00000001 855e52cc 84c47660 00000ebe 855c8a80 1de0: dfa41ea4 dfa41df0 80c29b04 813ae204 00000000 00000400 00000000 00000eb0 1e00: 00000000 83641800 dfa41ea4 dfa41e18 8031cb08 00010040 00000000 83641800 1e20: 00000000 0000ef31 0000fdef 00000000 855e5000 0000fdef 00000000 00080000 1e40: 855c8a80 00000000 00000000 00000000 00000000 00000000 00000400 00000000 1e60: 00000000 d2f4c1d4 8219b2bc 84c46660 84c46000 d2f4c1d4 83641800 dfa41f08 1e80: dfa41ef0 00000000 84c46660 855e5000 20000040 81b6cbe4 dfa41ed4 dfa41ea8 1ea0: 80c2acb8 80c290c4 00000001 00000000 00000008 80c2ac58 846f6d80 0000fdef 1ec0: 83641800 dfa41f68 dfa41f64 dfa41ed8 804f7298 80c2ac64 dfa41f04 dfa41ee8 1ee0: 8020c17c 8020d138 00000000 00000000 00010000 0000fdef 20000040 00000000 1f00: 00000001 00000000 846f6d80 00000000 0000002a 00000000 00000000 00000000 1f20: 00000000 00000000 00000000 00000000 0000fdef d2f4c1d4 83641800 846f6d81 1f40: 846f6d80 0000002a 00000000 80200288 83641800 00000004 dfa41f94 dfa41f68 1f60: 804f75e0 804f7030 0000002a 00000000 80203054 d2f4c1d4 0000fdef 20000040 1f80: 000000c8 00000004 dfa41fa4 dfa41f98 804f7670 804f7574 00000000 dfa41fa8 1fa0: 80200060 804f766c 0000fdef 20000040 000000c8 20000040 0000fdef 00000000 1fc0: 0000fdef 20000040 000000c8 00000004 7ed4d32e 7ed4d32f 003d0f00 76b160fc 1fe0: 0000005c 76b15ef0 00091154 0004f04c 40000010 000000c8 00000000 00000000 Call trace: [<803f2e4c>] (dev_map_generic_redirect) from [<813e318c>] (xdp_do_generic_redirect_map net/core/filter.c:4463 [inline]) [<803f2e4c>] (dev_map_generic_redirect) from [<813e318c>] (xdp_do_generic_redirect+0x1d8/0x4d4 net/core/filter.c:4520) r10:5b930000 r9:00000024 r8:0000000e r7:dfa41da4 r6:84c46000 r5:855c8a80 r4:824b3560 [<813e2fb4>] (xdp_do_generic_redirect) from [<813ae474>] (do_xdp_generic+0x27c/0x440 net/core/dev.c:5021) r10:00000000 r9:83404800 r8:83641800 r7:dfa43000 r6:0000000e r5:00000004 r4:dfa41e40 [<813ae1f8>] (do_xdp_generic) from [<80c29b04>] (tun_get_user+0xa4c/0x13f4 drivers/net/tun.c:1924) r9:855c8a80 r8:00000ebe r7:84c47660 r6:855e52cc r5:00000001 r4:84c46660 [<80c290b8>] (tun_get_user) from [<80c2acb8>] (tun_chr_write_iter+0x60/0xc8 drivers/net/tun.c:2048) r10:81b6cbe4 r9:20000040 r8:855e5000 r7:84c46660 r6:00000000 r5:dfa41ef0 r4:dfa41f08 [<80c2ac58>] (tun_chr_write_iter) from [<804f7298>] (call_write_iter include/linux/fs.h:2108 [inline]) [<80c2ac58>] (tun_chr_write_iter) from [<804f7298>] (new_sync_write fs/read_write.c:497 [inline]) [<80c2ac58>] (tun_chr_write_iter) from [<804f7298>] (vfs_write+0x274/0x438 fs/read_write.c:590) r8:dfa41f68 r7:83641800 r6:0000fdef r5:846f6d80 r4:80c2ac58 [<804f7024>] (vfs_write) from [<804f75e0>] (ksys_write+0x78/0xf8 fs/read_write.c:643) r10:00000004 r9:83641800 r8:80200288 r7:00000000 r6:0000002a r5:846f6d80 r4:846f6d81 [<804f7568>] (ksys_write) from [<804f7670>] (__do_sys_write fs/read_write.c:655 [inline]) [<804f7568>] (ksys_write) from [<804f7670>] (sys_write+0x10/0x14 fs/read_write.c:652) r7:00000004 r6:000000c8 r5:20000040 r4:0000fdef [<804f7660>] (sys_write) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66) Exception stack(0xdfa41fa8 to 0xdfa41ff0) 1fa0: 0000fdef 20000040 000000c8 20000040 0000fdef 00000000 1fc0: 0000fdef 20000040 000000c8 00000004 7ed4d32e 7ed4d32f 003d0f00 76b160fc 1fe0: 0000005c 76b15ef0 00091154 0004f04c Code: ee1d9f70 e1a08002 e591a054 e1a06000 (e597508c) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: ee1d9f70 mrc 15, 0, r9, cr13, cr0, {3} 4: e1a08002 mov r8, r2 8: e591a054 ldr sl, [r1, #84] @ 0x54 c: e1a06000 mov r6, r0 * 10: e597508c ldr r5, [r7, #140] @ 0x8c <-- trapping instruction