Now that I've wrapped up elsewhere, I can focus on this. Let me know if there's any questions.
Thanks, Paul [ 0.716942] ------------[ cut here ]------------ [ 0.717160] refcount_t: underflow; use-after-free. [ 0.717356] WARNING: CPU: 2 PID: 138 at lib/refcount.c:28 refcount_warn_saturate+0x118/0x180 [ 0.717661] Modules linked in: [ 0.717816] CPU: 2 UID: 1000 PID: 138 Comm: poc9 Not tainted 6.18.13 #3 PREEMPT(full) [ 0.718138] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 0.718591] RIP: 0010:refcount_warn_saturate+0x118/0x180 [ 0.718805] Code: 0f b6 05 aa bf 05 02 3c 01 0f 87 d7 db 5d ff a8 01 0f 85 39 ff ff ff 48 c7 c7 78 71 ec 82 c6 05 8c bf 05 02 01 e8 78 f0 78 ff <0f> 0b c9 31 c0 31 f6 31 ff e9 55 4c 45 ff 0f b6 05 73 bf 05 02 3c [ 0.719521] RSP: 0018:ffffc9000048b790 EFLAGS: 00010246 [ 0.719722] RAX: 0000000000000000 RBX: ffff888006c74200 RCX: 0000000000000000 [ 0.719985] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [poc9-vdpa] port[ 0.720257] RBP: ffffc9000048b798 R08: 0000000000000000 R09: 0000000000000000 id=135 rcvbuf=23[ 0.720580] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880075ea000 04 soerr=105 dro[ 0.720869] R13: ffff888006c74200 R14: 00000000fffffff5 R15: ffffc9000048b920 ps=0 get 2/0 sen[ 0.721165] FS: 000076880ed826c0(0000) GS:ffff88809a460000(0000) knlGS:0000000000000000 d_eagain=0 [ 0.721534] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.721768] CR2: 000076880ed801c8 CR3: 0000000008a61000 CR4: 0000000000450ef0 [ 0.722055] PKRU: 55555554 [ 0.722159] Call Trace: [ 0.722253] <TASK> [ 0.722339] sk_skb_reason_drop+0x203/0x210 [ 0.722512] ? up_read+0x22/0x30 [ 0.722638] vdpa_nl_cmd_dev_config_get_doit+0xc7/0x1d0 [ 0.722832] genl_family_rcv_msg_doit+0xcf/0x120 [ 0.723018] genl_rcv_msg+0x161/0x290 [ 0.723157] ? __pfx_vdpa_nl_cmd_dev_config_get_doit+0x10/0x10 [ 0.723381] ? __pfx_genl_rcv_msg+0x10/0x10 [ 0.727944] netlink_rcv_skb+0x41/0xf0 [ 0.728136] genl_rcv+0x28/0x50 [ 0.728281] netlink_unicast+0x1d8/0x2b0 [ 0.728483] netlink_sendmsg+0x212/0x440 [ 0.728673] __sys_sendto+0x1f3/0x200 [ 0.728859] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.729076] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.729287] ? __lock_acquire+0x831/0x2980 [ 0.729491] __x64_sys_sendto+0x24/0x40 [ 0.729665] x64_sys_call+0x1d15/0x2350 [ 0.729838] do_syscall_64+0x90/0xc60 [ 0.730010] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.730226] ? lock_acquire+0xcc/0x2e0 [ 0.730391] ? __folio_batch_add_and_move+0x24b/0x370 [ 0.730623] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.730835] ? find_held_lock+0x31/0x90 [ 0.731010] ? __folio_batch_add_and_move+0x1ab/0x370 [ 0.731238] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.731465] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.731677] ? find_held_lock+0x31/0x90 [ 0.731851] ? rcu_read_unlock+0x1f/0x80 [ 0.732029] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.732247] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.732474] ? rcu_read_unlock+0x29/0x80 [ 0.732652] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.732864] ? do_anonymous_page+0x101/0x840 [ 0.733055] ? ___pte_offset_map+0x1d2/0x290 [ 0.733255] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.733482] ? __handle_mm_fault+0xa8e/0xf40 [ 0.733693] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.733904] ? find_held_lock+0x31/0x90 [ 0.734079] ? exc_page_fault+0x98/0x2c0 [ 0.734257] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.734490] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.734709] ? do_user_addr_fault+0x37b/0x6e0 [ 0.734905] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.735118] ? irqentry_exit_to_user_mode+0xf4/0x300 [ 0.735340] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.735566] ? irqentry_exit+0x77/0xb0 [ 0.735737] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.735949] ? exc_page_fault+0xbf/0x2c0 [ 0.736124] ? srso_alias_return_thunk+0x5/0xfbef5 [ 0.736340] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 0.736576] RIP: 0033:0x434e6c [ 0.736720] Code: fa 6e 03 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c3 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 df 48 89 44 24 08 e8 40 6f 03 00 48 8b [ 0.737513] RSP: 002b:000076880ed80190 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [ 0.737841] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000434e6c [ 0.738154] RDX: 0000000000000020 RSI: 000076880ed801d0 RDI: 0000000000000003 [ 0.738473] RBP: 0000000069b8ab57 R08: 00000000004b3cf0 R09: 000000000000000c [ 0.738767] R10: 0000000000000000 R11: 0000000000000293 R12: 000000000f71e860 [ 0.739075] R13: 0000000000000013 R14: 000076880ed82cdc R15: 00007fff0dab68e7 [ 0.739415] </TASK> [ 0.739526] irq event stamp: 785 [ 0.739675] hardirqs last enabled at (793): [<ffffffff815153f0>] __up_console_sem+0x90/0xa0 [ 0.740039] hardirqs last disabled at (800): [<ffffffff815153d5>] __up_console_sem+0x75/0xa0 [ 0.740410] softirqs last enabled at (362): [<ffffffff81449bcd>] __irq_exit_rcu+0x12d/0x150 [ 0.740782] softirqs last disabled at (357): [<ffffffff81449bcd>] __irq_exit_rcu+0x12d/0x150 [ 0.741145] ---[ end trace 0000000000000000 ]--- [poc9-vdpa] portid=135 rcvbuf=2304 soerr=0 drops=0 get 98859/0 send_eagain=0 [poc9-vdpa] portid=135 rcvbuf=2304 soerr=0 drops=0 get 204383/0 send_eagain=0 [poc9-vdpa] portid=135 rcvbuf=2304 soerr=0 drops=0 get 319574/0 send_eagain=0 [ 4.037387] BUG: kernel NULL pointer dereference, address: 0000000000000060 [ 4.037612] #PF: supervisor read access in kernel mode [ 4.037761] #PF: error_code(0x0000) - not-present page [ 4.037914] PGD 994c067 P4D 994c067 PUD 994d067 PMD 0 [ 4.038066] Oops: Oops: 0000 [#1] SMP NOPTI [ 4.038191] CPU: 4 UID: 1000 PID: 140 Comm: poc9 Tainted: G W 6.18.13 #3 PREEMPT(full) [ 4.038463] Tainted: [W]=WARN [ 4.038557] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 4.038869] RIP: 0010:sock_wfree+0x1d/0x3f0 [ 4.038994] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 53 48 83 ec 10 48 8b 5f 18 44 8b 97 d8 00 00 00 <48> 8b 43 60 f6 c4 02 74 51 44 89 d0 44 89 d2 48 8d 8b 94 02 00 00 [ 4.039511] RSP: 0018:ffffc9000049b8f0 EFLAGS: 00010286 [ 4.039665] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 4.039874] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801f8aa100 [ 4.040076] RBP: ffffc9000049b918 R08: 0000000000000000 R09: 0000000000000000 [ 4.040278] R10: 00000000000003c0 R11: 0000000000000000 R12: ffff8880075ea000 [ 4.040482] R13: ffff88801f8aa100 R14: 00000000fffffff5 R15: ffffc9000049baf0 [ 4.040685] FS: 000076880dd806c0(0000) GS:ffff88809a560000(0000) knlGS:0000000000000000 [ 4.040908] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.041071] CR2: 0000000000000060 CR3: 0000000008a61000 CR4: 0000000000450ef0 [ 4.041275] PKRU: 55555554 [ 4.041356] Call Trace: [ 4.041434] <TASK> [ 4.041502] unix_destruct_scm+0x77/0x90 [ 4.041620] skb_release_head_state+0x27/0xb0 [ 4.041750] sk_skb_reason_drop+0x55/0x210 [ 4.041868] ? up_read+0x22/0x30 [ 4.041976] vdpa_nl_cmd_dev_config_get_doit+0xc7/0x1d0 [ 4.042140] genl_family_rcv_msg_doit+0xcf/0x120 [ 4.042280] genl_rcv_msg+0x161/0x290 [ 4.042387] ? __pfx_vdpa_nl_cmd_dev_config_get_doit+0x10/0x10 [ 4.042558] ? __pfx_genl_rcv_msg+0x10/0x10 [ 4.042679] netlink_rcv_skb+0x41/0xf0 [ 4.042798] genl_rcv+0x28/0x50 [ 4.042892] netlink_unicast+0x1d8/0x2b0 [ 4.043009] netlink_sendmsg+0x212/0x440 [ 4.043127] __sys_sendto+0x1f3/0x200 [ 4.043238] ? __sys_sendto+0x1aa/0x200 [ 4.043351] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.043493] ? x64_sys_call+0x1d15/0x2350 [ 4.043610] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.043747] ? do_syscall_64+0x1b5/0xc60 [ 4.043867] __x64_sys_sendto+0x24/0x40 [ 4.043979] x64_sys_call+0x1d15/0x2350 [ 4.044091] do_syscall_64+0x90/0xc60 [ 4.044200] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.044337] ? x64_sys_call+0x1d15/0x2350 [ 4.044456] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.044597] ? do_syscall_64+0x1b5/0xc60 [ 4.044712] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.044851] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.044990] ? x64_sys_call+0x1d15/0x2350 [ 4.045106] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.045243] ? do_syscall_64+0x1b5/0xc60 [ 4.045358] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.045498] ? x64_sys_call+0x1d15/0x2350 [ 4.045614] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.045750] ? do_syscall_64+0x1b5/0xc60 [ 4.045863] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.046007] ? do_syscall_64+0x1b5/0xc60 [ 4.046121] ? srso_alias_return_thunk+0x5/0xfbef5 [ 4.046259] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 4.046407] RIP: 0033:0x434e6c [ 4.046500] Code: fa 6e 03 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c3 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 df 48 89 44 24 08 e8 40 6f 03 00 48 8b [ 4.047008] RSP: 002b:000076880dd7e190 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [ 4.047218] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000434e6c [ 4.047420] RDX: 0000000000000020 RSI: 000076880dd7e1d0 RDI: 0000000000000003 [ 4.047618] RBP: 0000000069b93bd6 R08: 00000000004b3cf0 R09: 000000000000000c [ 4.047816] R10: 0000000000000000 R11: 0000000000000293 R12: 000000000f71e860 [ 4.048023] R13: 0000000000000013 R14: 000076880dd80cdc R15: 00007fff0dab68e7 [ 4.048228] </TASK> [ 4.048295] Modules linked in: [ 4.048387] CR2: 0000000000000060 [ 4.048494] ---[ end trace 0000000000000000 ]--- [ 4.059378] RIP: 0010:sock_wfree+0x1d/0x3f0 [ 4.059511] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 53 48 83 ec 10 48 8b 5f 18 44 8b 97 d8 00 00 00 <48> 8b 43 60 f6 c4 02 74 51 44 89 d0 44 89 d2 48 8d 8b 94 02 00 00 [ 4.060019] RSP: 0018:ffffc9000049b8f0 EFLAGS: 00010286 [ 4.060168] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 4.060367] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801f8aa100 [ 4.060574] RBP: ffffc9000049b918 R08: 0000000000000000 R09: 0000000000000000 [ 4.060776] R10: 00000000000003c0 R11: 0000000000000000 R12: ffff8880075ea000 [ 4.060978] R13: ffff88801f8aa100 R14: 00000000fffffff5 R15: ffffc9000049baf0 [ 4.061183] FS: 000076880dd806c0(0000) GS:ffff88809a560000(0000) knlGS:0000000000000000 [ 4.061416] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.061579] CR2: 0000000000000060 CR3: 0000000008a61000 CR4: 0000000000450ef0 [ 4.061782] PKRU: 55555554 [ 4.061863] Kernel panic - not syncing: Fatal exception [ 4.062096] Kernel Offset: disabled [ 4.062204] Rebooting in 1 seconds..
