While running selftest bpf: test_sockmap the kernel BUG found on i386 and arm kernel running on Linux version 5.2.0-rc5-next-20190617 steps to reproduce, cd /opt/kselftests/default-in-kernel/bpf ./test_sockmap [ 33.666964] BUG: kernel NULL pointer dereference, address: 00000000 [ 33.673246] #PF: supervisor read access in kernel mode [ 33.678392] #PF: error_code(0x0000) - not-present page [ 33.683539] *pde = 00000000 [ 33.686435] Oops: 0000 [#1] SMP [ 33.689593] CPU: 1 PID: 619 Comm: test_sockmap Not tainted 5.2.0-rc5-next-20190617 #1 [ 33.697431] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS 2.0b 07/27/2017 [ 33.704914] EIP: memcpy+0x1d/0x30 [ 33.708240] Code: 59 58 eb 85 90 90 90 90 90 90 90 90 90 3e 8d 74 26 00 55 89 e5 57 56 89 c7 53 89 d6 89 cb c1 e9 02 f3 a5 89 d9 83 e1 03 74 02 <f3> a4 5b 5e 5f 5d c3 8d b6 00 00 00 00 8d bf 00 00 00 00 3e 8d 74 [ 33.726985] EAX: f1faf000 EBX: 00000001 ECX: 00000001 EDX: 00000000 [ 33.733249] ESI: 00000000 EDI: f1faf000 EBP: f2e6d99c ESP: f2e6d990 [ 33.739505] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010202 [ 33.746283] CR0: 80050033 CR2: 00000000 CR3: 31fae000 CR4: 003406d0 [ 33.752542] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 33.758807] DR6: fffe0ff0 DR7: 00000400 [ 33.762638] Call Trace: [ 33.765084] bpf_msg_push_data+0x635/0x660 [ 33.769183] ? _raw_spin_unlock_irqrestore+0x2f/0x50 [ 33.774150] ? lockdep_hardirqs_on+0xec/0x1a0 [ 33.778512] ___bpf_prog_run+0xa0d/0x15a0 [ 33.782523] ? __lock_acquire+0x1fe/0x1ec0 [ 33.786621] __bpf_prog_run32+0x4b/0x70 [ 33.790462] ? sk_psock_msg_verdict+0x5/0x290 [ 33.794819] sk_psock_msg_verdict+0xad/0x290 [ 33.799091] ? sk_psock_msg_verdict+0xad/0x290 [ 33.803537] ? lockdep_hardirqs_on+0xec/0x1a0 [ 33.807887] ? __local_bh_enable_ip+0x78/0xf0 [ 33.812238] tcp_bpf_send_verdict+0x29c/0x3b0 [ 33.816590] tcp_bpf_sendpage+0x233/0x3d0 [ 33.820603] ? __lock_acquire+0x1fe/0x1ec0 [ 33.824703] ? __lock_acquire+0x1fe/0x1ec0 [ 33.828801] ? find_held_lock+0x27/0xa0 [ 33.832640] ? lock_release+0x92/0x290 [ 33.836392] ? find_get_entry+0x136/0x300 [ 33.840397] ? touch_atime+0x34/0xd0 [ 33.843978] ? copy_page_to_iter+0x245/0x400 [ 33.848248] ? lockdep_hardirqs_on+0xec/0x1a0 [ 33.852600] ? tcp_bpf_send_verdict+0x3b0/0x3b0 [ 33.857132] inet_sendpage+0x53/0x1f0 [ 33.860789] ? inet_recvmsg+0x1e0/0x1e0 [ 33.864620] ? kernel_sendpage+0x40/0x40 [ 33.868536] kernel_sendpage+0x1e/0x40 [ 33.872282] sock_sendpage+0x24/0x30 [ 33.875861] pipe_to_sendpage+0x59/0xa0 [ 33.879692] ? direct_splice_actor+0x40/0x40 [ 33.883962] __splice_from_pipe+0xde/0x1c0 [ 33.888055] ? direct_splice_actor+0x40/0x40 [ 33.892342] ? direct_splice_actor+0x40/0x40 [ 33.896635] splice_from_pipe+0x59/0x80 [ 33.900466] ? splice_from_pipe+0x80/0x80 [ 33.904469] ? generic_splice_sendpage+0x20/0x20 [ 33.909080] generic_splice_sendpage+0x18/0x20 [ 33.913516] ? direct_splice_actor+0x40/0x40 [ 33.917782] direct_splice_actor+0x2d/0x40 [ 33.921880] splice_direct_to_actor+0x127/0x240 [ 33.926403] ? generic_pipe_buf_nosteal+0x10/0x10 [ 33.931105] do_splice_direct+0x7e/0xc0 [ 33.934944] do_sendfile+0x20d/0x3e0 [ 33.938522] sys_sendfile+0xac/0xd0 [ 33.942015] do_fast_syscall_32+0x8e/0x320 [ 33.946114] entry_SYSENTER_32+0x70/0xc8 [ 33.950039] EIP: 0xb7fa67a1 [ 33.952830] Code: 8b 98 60 cd ff ff 85 d2 89 c8 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 1c 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d 76 00 58 b8 77 00 00 00 cd 80 90 8d 76 [ 33.971567] EAX: ffffffda EBX: 00000018 ECX: 0000001c EDX: 00000000 [ 33.977823] ESI: 00000001 EDI: 00000018 EBP: 00000001 ESP: bfcaa6d4 [ 33.984083] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000206 [ 33.990869] Modules linked in: x86_pkg_temp_thermal fuse [ 33.996181] CR2: 0000000000000000 [ 33.999500] ---[ end trace 0ef7a1496c65bde8 ]--- - Naresh
