From 3705e11a21bcdffe7422ee7870e1b23fe4ac70f4 Mon Sep 17 00:00:00 2001 From: Yang Hongyang Date: Fri, 18 Dec 2009 20:25:13 -0800 Subject: ipv6: fix an oops when force unload ipv6 module When I do an ipv6 module force unload,I got the following oops: #rmmod -f ipv6 ------------[ cut here ]------------ kernel BUG at mm/slub.c:2969! invalid opcode: 0000 [#1] SMP last sysfs file: /sys/devices/pci0000:00/0000:00:11.0/0000:02:03.0/net/eth2/ifindex Modules linked in: ipv6(-) dm_multipath uinput ppdev tpm_tis tpm tpm_bios pcspkr pcnet32 mii parport_pc i2c_piix4 parport i2c_core floppy mptspi mptscsih mptbase scsi_transport_spi Pid: 2530, comm: rmmod Tainted: G R 2.6.32 #2 440BX Desktop Reference Platform/VMware Virtual Platform EIP: 0060:[] EFLAGS: 00010246 CPU: 0 EIP is at kfree+0x6a/0xdd EAX: 00000000 EBX: c09e86bc ECX: c043e4dd EDX: c14293e0 ESI: e141f1d8 EDI: e140fc31 EBP: dec58ef0 ESP: dec58ed0 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 Process rmmod (pid: 2530, ti=dec58000 task=decb1940 task.ti=dec58000) Stack: c14293e0 00000282 df624240 c0897d08 c09e86bc c09e86bc e141f1d8 dec58f1c <0> dec58f00 e140fc31 c09e84c4 e141f1bc dec58f14 c0689d21 dec58f1c e141f1bc <0> 00000000 dec58f2c c0689eff c09e84d8 c09e84d8 e141f1bc bff33a90 dec58f38 Call Trace: [] ? ipv6_frags_exit_net+0x22/0x32 [ipv6] [] ? ops_exit_list+0x19/0x3d [] ? unregister_pernet_operations+0x2a/0x51 [] ? unregister_pernet_subsys+0x17/0x24 [] ? ipv6_frag_exit+0x21/0x32 [ipv6] [] ? inet6_exit+0x47/0x122 [ipv6] [] ? sys_delete_module+0x198/0x1f6 [] ? remove_vma+0x57/0x5d [] ? do_page_fault+0x2e7/0x315 [] ? sysenter_do_call+0x12/0x28 Code: 86 00 00 00 40 c1 e8 0c c1 e0 05 01 d0 89 45 e0 66 83 38 00 79 06 8b 40 0c 89 45 e0 8b 55 e0 8b 02 84 c0 78 14 66 a9 00 c0 75 04 <0f> 0b eb fe 8b 45 e0 e8 35 15 fe ff eb 5d 8b 45 04 8b 55 e0 89 EIP: [] kfree+0x6a/0xdd SS:ESP 0068:dec58ed0 ---[ end trace 4475d1a5b0afa7e5 ]--- It's because in ip6_frags_ns_sysctl_register, "table" only alloced when "net" is not equals to "init_net".So when we free "table" in ip6_frags_ns_sysctl_unregister,we should check this first. This patch fix the problem. Signed-off-by: Yang Hongyang Signed-off-by: David S. Miller --- net/ipv6/reassembly.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 3b3a9560712..2cddea3bd6b 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -708,7 +708,8 @@ static void ip6_frags_ns_sysctl_unregister(struct net *net) table = net->ipv6.sysctl.frags_hdr->ctl_table_arg; unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr); - kfree(table); + if (!net_eq(net, &init_net)) + kfree(table); } static struct ctl_table_header *ip6_ctl_header; -- cgit v1.2.3