| Message ID | 873ajg1xa0.fsf@natisbad.org |
|---|---|
| State | Accepted, archived |
| Headers | show |
From: arno@natisbad.org (Arnaud Ebalard) Date: Wed, 01 Oct 2008 11:26:31 +0200 > With the switch to a default value of 1 for xfrm_larval_drop in commit > 28faa979746b2352cd78a376bf9f52db953bda46 (ipsec: Make xfrm_larval_drop > default to 1), what seems to be a bug manage to surface on one of my > test box running today's net-next (*). > > When xfrm_tmpl_resolve() returns -EAGAIN in __xfrm_lookup(), the caller > is returned -EREMOTE and is expected to install a blackhole route. For > IPv6, the call to dst_alloc(&ip6_dst_blackhole_ops) performed by > ip6_dst_blackhole() produces the error provided below, because > kmem_cachep attribute seems to be uninitialized. This does not happen > when xfrm_larval_drop is set to 0. > > The patch below against today's net-next. Benjamin (in CC) reported on > the introduction of the bug (f2fc6a54585a1be6669613a31fbaba2ecbadcd36) > while adding network namespaces support to ipv6 routes. Applied to net-2.6, thanks Arnaud! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
David Miller <davem@davemloft.net> writes: > From: arno@natisbad.org (Arnaud Ebalard) > Date: Wed, 01 Oct 2008 11:26:31 +0200 > >> With the switch to a default value of 1 for xfrm_larval_drop in commit >> 28faa979746b2352cd78a376bf9f52db953bda46 (ipsec: Make xfrm_larval_drop >> default to 1), what seems to be a bug manage to surface on one of my >> test box running today's net-next (*). >> >> When xfrm_tmpl_resolve() returns -EAGAIN in __xfrm_lookup(), the caller >> is returned -EREMOTE and is expected to install a blackhole route. For >> IPv6, the call to dst_alloc(&ip6_dst_blackhole_ops) performed by >> ip6_dst_blackhole() produces the error provided below, because >> kmem_cachep attribute seems to be uninitialized. This does not happen >> when xfrm_larval_drop is set to 0. >> >> The patch below against today's net-next. Benjamin (in CC) reported on >> the introduction of the bug (f2fc6a54585a1be6669613a31fbaba2ecbadcd36) >> while adding network namespaces support to ipv6 routes. > > Applied to net-2.6, thanks Arnaud! Can you queue it for -stable (2.6.26) too, if not already done? a+ -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: arno@natisbad.org (Arnaud Ebalard) Date: Wed, 01 Oct 2008 14:59:32 +0200 > David Miller <davem@davemloft.net> writes: > > > > Applied to net-2.6, thanks Arnaud! > > Can you queue it for -stable (2.6.26) too, if not already done? Done. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 776871e..f4385a6 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2708,6 +2708,8 @@ int __init ip6_route_init(void) if (ret) goto out_kmem_cache; + ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep; + /* Registering of the loopback is done before this portion of code, * the loopback reference in rt6_info will not be taken, do it * manually for init_net */
Hi, This is a resend. Sorry if it was already on your todo list, David. With the switch to a default value of 1 for xfrm_larval_drop in commit 28faa979746b2352cd78a376bf9f52db953bda46 (ipsec: Make xfrm_larval_drop default to 1), what seems to be a bug manage to surface on one of my test box running today's net-next (*). When xfrm_tmpl_resolve() returns -EAGAIN in __xfrm_lookup(), the caller is returned -EREMOTE and is expected to install a blackhole route. For IPv6, the call to dst_alloc(&ip6_dst_blackhole_ops) performed by ip6_dst_blackhole() produces the error provided below, because kmem_cachep attribute seems to be uninitialized. This does not happen when xfrm_larval_drop is set to 0. The patch below against today's net-next. Benjamin (in CC) reported on the introduction of the bug (f2fc6a54585a1be6669613a31fbaba2ecbadcd36) while adding network namespaces support to ipv6 routes. The patch is also a good candidate for 2.6.27-rc9 and current stable kernel (2.6.26.5). Cheers, a+ (*): with the small MIGRATE patch David commented some days ago applied on top of it. No interaction expected. From: Arnaud Ebalard <arno@natisbad.org> Date: Wed, 1 Oct 2008 10:54:34 +0200 Subject: [PATCH] XFRM,IPv6: initialize ip6_dst_blackhole_ops.kmem_cachep ip6_dst_blackhole_ops.kmem_cachep is not expected to be NULL (i.e. to be initialized) when dst_alloc() is called from ip6_dst_blackhole(). Otherwise, it results in the following (xfrm_larval_drop is now set to 1 by default): [ 78.697642] Unable to handle kernel paging request for data at address 0x0000004c [ 78.703449] Faulting instruction address: 0xc0097f54 [ 78.786896] Oops: Kernel access of bad area, sig: 11 [#1] [ 78.792791] PowerMac [ 78.798383] Modules linked in: btusb usbhid bluetooth b43 mac80211 cfg80211 ehci_hcd ohci_hcd sungem sungem_phy usbcore ssb [ 78.804263] NIP: c0097f54 LR: c0334a28 CTR: c002d430 [ 78.809997] REGS: eef19ad0 TRAP: 0300 Not tainted (2.6.27-rc5) [ 78.815743] MSR: 00001032 <ME,IR,DR> CR: 22242482 XER: 20000000 [ 78.821550] DAR: 0000004c, DSISR: 40000000 [ 78.827278] TASK = eef0df40[3035] 'mip6d' THREAD: eef18000 [ 78.827408] GPR00: 00001032 eef19b80 eef0df40 00000000 00008020 eef19c30 00000001 00000000 [ 78.833249] GPR08: eee5101c c05a5c10 ef9ad500 00000000 24242422 1005787c 00000000 1004f960 [ 78.839151] GPR16: 00000000 10024e90 10050040 48030018 0fe44150 00000000 00000000 eef19c30 [ 78.845046] GPR24: eef19e44 00000000 eef19bf8 efb37c14 eef19bf8 00008020 00009032 c0596064 [ 78.856671] NIP [c0097f54] kmem_cache_alloc+0x20/0x94 [ 78.862581] LR [c0334a28] dst_alloc+0x40/0xc4 [ 78.868451] Call Trace: [ 78.874252] [eef19b80] [c03c1810] ip6_dst_lookup_tail+0x1c8/0x1dc (unreliable) [ 78.880222] [eef19ba0] [c0334a28] dst_alloc+0x40/0xc4 [ 78.886164] [eef19bb0] [c03cd698] ip6_dst_blackhole+0x28/0x1cc [ 78.892090] [eef19be0] [c03d9be8] rawv6_sendmsg+0x75c/0xc88 [ 78.897999] [eef19cb0] [c038bca4] inet_sendmsg+0x4c/0x78 [ 78.903907] [eef19cd0] [c03207c8] sock_sendmsg+0xac/0xe4 [ 78.909734] [eef19db0] [c03209e4] sys_sendmsg+0x1e4/0x2a0 [ 78.915540] [eef19f00] [c03220a8] sys_socketcall+0xfc/0x210 [ 78.921406] [eef19f40] [c0014b3c] ret_from_syscall+0x0/0x38 [ 78.927295] --- Exception: c01 at 0xfe2d730 [ 78.927297] LR = 0xfe2d71c [ 78.939019] Instruction dump: [ 78.944835] 91640018 9144001c 900a0000 4bffff44 9421ffe0 7c0802a6 bf810010 7c9d2378 [ 78.950694] 90010024 7fc000a6 57c0045e 7c000124 <83e3004c> 8383005c 2f9f0000 419e0050 [ 78.956464] ---[ end trace 05fa1ed7972487a1 ]--- As commented by Benjamin Thery, the bug was introduced by f2fc6a54585a1be6669613a31fbaba2ecbadcd36, while adding network namespaces support to ipv6 routes. Signed-off-by: Arnaud Ebalard <arno@natisbad.org> Acked-by: Benjamin Thery <benjamin.thery@bull.net> --- net/ipv6/route.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)