| From 35da819b34ff73bb2a1bf629a11a1d15feb19190 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 16 Dec 2021 03:17:41 -0800 |
| Subject: sit: do not call ipip6_dev_free() from sit_init_net() |
| |
| From: Eric Dumazet <edumazet@google.com> |
| |
| [ Upstream commit e28587cc491ef0f3c51258fdc87fbc386b1d4c59 ] |
| |
| ipip6_dev_free is sit dev->priv_destructor, already called |
| by register_netdevice() if something goes wrong. |
| |
| Alternative would be to make ipip6_dev_free() robust against |
| multiple invocations, but other drivers do not implement this |
| strategy. |
| |
| syzbot reported: |
| |
| dst_release underflow |
| WARNING: CPU: 0 PID: 5059 at net/core/dst.c:173 dst_release+0xd8/0xe0 net/core/dst.c:173 |
| Modules linked in: |
| CPU: 1 PID: 5059 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0 |
| Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 |
| RIP: 0010:dst_release+0xd8/0xe0 net/core/dst.c:173 |
| Code: 4c 89 f2 89 d9 31 c0 5b 41 5e 5d e9 da d5 44 f9 e8 1d 90 5f f9 c6 05 87 48 c6 05 01 48 c7 c7 80 44 99 8b 31 c0 e8 e8 67 29 f9 <0f> 0b eb 85 0f 1f 40 00 53 48 89 fb e8 f7 8f 5f f9 48 83 c3 a8 48 |
| RSP: 0018:ffffc9000aa5faa0 EFLAGS: 00010246 |
| RAX: d6894a925dd15a00 RBX: 00000000ffffffff RCX: 0000000000040000 |
| RDX: ffffc90005e19000 RSI: 000000000003ffff RDI: 0000000000040000 |
| RBP: 0000000000000000 R08: ffffffff816a1f42 R09: ffffed1017344f2c |
| R10: ffffed1017344f2c R11: 0000000000000000 R12: 0000607f462b1358 |
| R13: 1ffffffff1bfd305 R14: ffffe8ffffcb1358 R15: dffffc0000000000 |
| FS: 00007f66c71a2700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 00007f88aaed5058 CR3: 0000000023e0f000 CR4: 00000000003506f0 |
| DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 |
| DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 |
| Call Trace: |
| <TASK> |
| dst_cache_destroy+0x107/0x1e0 net/core/dst_cache.c:160 |
| ipip6_dev_free net/ipv6/sit.c:1414 [inline] |
| sit_init_net+0x229/0x550 net/ipv6/sit.c:1936 |
| ops_init+0x313/0x430 net/core/net_namespace.c:140 |
| setup_net+0x35b/0x9d0 net/core/net_namespace.c:326 |
| copy_net_ns+0x359/0x5c0 net/core/net_namespace.c:470 |
| create_new_namespaces+0x4ce/0xa00 kernel/nsproxy.c:110 |
| unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 |
| ksys_unshare+0x57d/0xb50 kernel/fork.c:3075 |
| __do_sys_unshare kernel/fork.c:3146 [inline] |
| __se_sys_unshare kernel/fork.c:3144 [inline] |
| __x64_sys_unshare+0x34/0x40 kernel/fork.c:3144 |
| do_syscall_x64 arch/x86/entry/common.c:50 [inline] |
| do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 |
| entry_SYSCALL_64_after_hwframe+0x44/0xae |
| RIP: 0033:0x7f66c882ce99 |
| Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 |
| RSP: 002b:00007f66c71a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 |
| RAX: ffffffffffffffda RBX: 00007f66c893ff60 RCX: 00007f66c882ce99 |
| RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000048040200 |
| RBP: 00007f66c8886ff1 R08: 0000000000000000 R09: 0000000000000000 |
| R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 |
| R13: 00007fff6634832f R14: 00007f66c71a2300 R15: 0000000000022000 |
| </TASK> |
| |
| Fixes: cf124db566e6 ("net: Fix inconsistent teardown and release of private netdev state.") |
| Signed-off-by: Eric Dumazet <edumazet@google.com> |
| Reported-by: syzbot <syzkaller@googlegroups.com> |
| Link: https://lore.kernel.org/r/20211216111741.1387540-1-eric.dumazet@gmail.com |
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| net/ipv6/sit.c | 1 - |
| 1 file changed, 1 deletion(-) |
| |
| diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c |
| index ef0c7a7c18e23..626cb53aa57ab 100644 |
| --- a/net/ipv6/sit.c |
| +++ b/net/ipv6/sit.c |
| @@ -1933,7 +1933,6 @@ static int __net_init sit_init_net(struct net *net) |
| return 0; |
| |
| err_reg_dev: |
| - ipip6_dev_free(sitn->fb_tunnel_dev); |
| free_netdev(sitn->fb_tunnel_dev); |
| err_alloc_dev: |
| return err; |
| -- |
| 2.33.0 |
| |