From da86299fcccb7cd1073e927068fc2f43fe5b9f8f Mon Sep 17 00:00:00 2001 From: Jonathan Lemon Date: Sun, 14 Apr 2019 14:21:29 -0700 Subject: route: Avoid crash from dereferencing NULL rt->from [ Upstream commit 9c69a13205151c0d801de9f9d83a818e6e8f60ec ] When __ip6_rt_update_pmtu() is called, rt->from is RCU dereferenced, but is never checked for null - rt6_flush_exceptions() may have removed the entry. [ 1913.989004] RIP: 0010:ip6_rt_cache_alloc+0x13/0x170 [ 1914.209410] Call Trace: [ 1914.214798] [ 1914.219226] __ip6_rt_update_pmtu+0xb0/0x190 [ 1914.228649] ip6_tnl_xmit+0x2c2/0x970 [ip6_tunnel] [ 1914.239223] ? ip6_tnl_parse_tlv_enc_lim+0x32/0x1a0 [ip6_tunnel] [ 1914.252489] ? __gre6_xmit+0x148/0x530 [ip6_gre] [ 1914.262678] ip6gre_tunnel_xmit+0x17e/0x3c7 [ip6_gre] [ 1914.273831] dev_hard_start_xmit+0x8d/0x1f0 [ 1914.283061] sch_direct_xmit+0xfa/0x230 [ 1914.291521] __qdisc_run+0x154/0x4b0 [ 1914.299407] net_tx_action+0x10e/0x1f0 [ 1914.307678] __do_softirq+0xca/0x297 [ 1914.315567] irq_exit+0x96/0xa0 [ 1914.322494] smp_apic_timer_interrupt+0x68/0x130 [ 1914.332683] apic_timer_interrupt+0xf/0x20 [ 1914.341721] Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected") Signed-off-by: Jonathan Lemon Reviewed-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Martin KaFai Lau Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/route.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/ipv6') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 0086acc16f3c..b6a97115a906 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2336,6 +2336,10 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk, rcu_read_lock(); from = rcu_dereference(rt6->from); + if (!from) { + rcu_read_unlock(); + return; + } nrt6 = ip6_rt_cache_alloc(from, daddr, saddr); if (nrt6) { rt6_do_update_pmtu(nrt6, mtu); -- cgit v1.2.3 From f0028f723428b623dd990d34f711acb84e0d9e51 Mon Sep 17 00:00:00 2001 From: Kangjie Lu Date: Thu, 14 Mar 2019 02:58:18 -0500 Subject: netfilter: ip6t_srh: fix NULL pointer dereferences [ Upstream commit 6d65561f3d5ec933151939c543d006b79044e7a6 ] skb_header_pointer may return NULL. The current code dereference its return values without a NULL check. The fix inserts the checks to avoid NULL pointer dereferences. Fixes: 202a8ff545cc ("netfilter: add IPv6 segment routing header 'srh' match") Signed-off-by: Kangjie Lu Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin (Microsoft) --- net/ipv6/netfilter/ip6t_srh.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'net/ipv6') diff --git a/net/ipv6/netfilter/ip6t_srh.c b/net/ipv6/netfilter/ip6t_srh.c index 1059894a6f4c..4cb83fb69844 100644 --- a/net/ipv6/netfilter/ip6t_srh.c +++ b/net/ipv6/netfilter/ip6t_srh.c @@ -210,6 +210,8 @@ static bool srh1_mt6(const struct sk_buff *skb, struct xt_action_param *par) psidoff = srhoff + sizeof(struct ipv6_sr_hdr) + ((srh->segments_left + 1) * sizeof(struct in6_addr)); psid = skb_header_pointer(skb, psidoff, sizeof(_psid), &_psid); + if (!psid) + return false; if (NF_SRH_INVF(srhinfo, IP6T_SRH_INV_PSID, ipv6_masked_addr_cmp(psid, &srhinfo->psid_msk, &srhinfo->psid_addr))) @@ -223,6 +225,8 @@ static bool srh1_mt6(const struct sk_buff *skb, struct xt_action_param *par) nsidoff = srhoff + sizeof(struct ipv6_sr_hdr) + ((srh->segments_left - 1) * sizeof(struct in6_addr)); nsid = skb_header_pointer(skb, nsidoff, sizeof(_nsid), &_nsid); + if (!nsid) + return false; if (NF_SRH_INVF(srhinfo, IP6T_SRH_INV_NSID, ipv6_masked_addr_cmp(nsid, &srhinfo->nsid_msk, &srhinfo->nsid_addr))) @@ -233,6 +237,8 @@ static bool srh1_mt6(const struct sk_buff *skb, struct xt_action_param *par) if (srhinfo->mt_flags & IP6T_SRH_LSID) { lsidoff = srhoff + sizeof(struct ipv6_sr_hdr); lsid = skb_header_pointer(skb, lsidoff, sizeof(_lsid), &_lsid); + if (!lsid) + return false; if (NF_SRH_INVF(srhinfo, IP6T_SRH_INV_LSID, ipv6_masked_addr_cmp(lsid, &srhinfo->lsid_msk, &srhinfo->lsid_addr))) -- cgit v1.2.3 From c61a4beb31f0c92580a66c660d359049692dc1aa Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Tue, 30 Apr 2019 10:45:12 -0700 Subject: ipv6: A few fixes on dereferencing rt->from [ Upstream commit 886b7a50100a50f1cbd08a6f8ec5884dfbe082dc ] It is a followup after the fix in commit 9c69a1320515 ("route: Avoid crash from dereferencing NULL rt->from") rt6_do_redirect(): 1. NULL checking is needed on rt->from because a parallel fib6_info delete could happen that sets rt->from to NULL. (e.g. rt6_remove_exception() and fib6_drop_pcpu_from()). 2. fib6_info_hold() is not enough. Same reason as (1). Meaning, holding dst->__refcnt cannot ensure rt->from is not NULL or rt->from->fib6_ref is not 0. Instead of using fib6_info_hold_safe() which ip6_rt_cache_alloc() is already doing, this patch chooses to extend the rcu section to keep "from" dereference-able after checking for NULL. inet6_rtm_getroute(): 1. NULL checking is also needed on rt->from for a similar reason. Note that inet6_rtm_getroute() is using RTNL_FLAG_DOIT_UNLOCKED. Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected") Signed-off-by: Martin KaFai Lau Acked-by: Wei Wang Reviewed-by: David Ahern Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/route.c | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index b6a97115a906..9f132e471d7a 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3403,11 +3403,8 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu rcu_read_lock(); from = rcu_dereference(rt->from); - /* This fib6_info_hold() is safe here because we hold reference to rt - * and rt already holds reference to fib6_info. - */ - fib6_info_hold(from); - rcu_read_unlock(); + if (!from) + goto out; nrt = ip6_rt_cache_alloc(from, &msg->dest, NULL); if (!nrt) @@ -3419,10 +3416,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key; - /* No need to remove rt from the exception table if rt is - * a cached route because rt6_insert_exception() will - * takes care of it - */ + /* rt6_insert_exception() will take care of duplicated exceptions */ if (rt6_insert_exception(nrt, from)) { dst_release_immediate(&nrt->dst); goto out; @@ -3435,7 +3429,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu call_netevent_notifiers(NETEVENT_REDIRECT, &netevent); out: - fib6_info_release(from); + rcu_read_unlock(); neigh_release(neigh); } @@ -4957,16 +4951,20 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, rcu_read_lock(); from = rcu_dereference(rt->from); - - if (fibmatch) - err = rt6_fill_node(net, skb, from, NULL, NULL, NULL, iif, - RTM_NEWROUTE, NETLINK_CB(in_skb).portid, - nlh->nlmsg_seq, 0); - else - err = rt6_fill_node(net, skb, from, dst, &fl6.daddr, - &fl6.saddr, iif, RTM_NEWROUTE, - NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, - 0); + if (from) { + if (fibmatch) + err = rt6_fill_node(net, skb, from, NULL, NULL, NULL, + iif, RTM_NEWROUTE, + NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, 0); + else + err = rt6_fill_node(net, skb, from, dst, &fl6.daddr, + &fl6.saddr, iif, RTM_NEWROUTE, + NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, 0); + } else { + err = -ENETUNREACH; + } rcu_read_unlock(); if (err < 0) { -- cgit v1.2.3 From d0aa794674e5df18e98f6fa2c2a80f8a4d134ad4 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 28 Apr 2019 12:22:25 -0700 Subject: ipv6: fix races in ip6_dst_destroy() [ Upstream commit 0e2338749192ce0e52e7174c5352f627632f478a ] We had many syzbot reports that seem to be caused by use-after-free of struct fib6_info. ip6_dst_destroy(), fib6_drop_pcpu_from() and rt6_remove_exception() are writers vs rt->from, and use non consistent synchronization among themselves. Switching to xchg() will solve the issues with no possible lockdep issues. BUG: KASAN: user-memory-access in atomic_dec_and_test include/asm-generic/atomic-instrumented.h:747 [inline] BUG: KASAN: user-memory-access in fib6_info_release include/net/ip6_fib.h:294 [inline] BUG: KASAN: user-memory-access in fib6_info_release include/net/ip6_fib.h:292 [inline] BUG: KASAN: user-memory-access in fib6_drop_pcpu_from net/ipv6/ip6_fib.c:927 [inline] BUG: KASAN: user-memory-access in fib6_purge_rt+0x4f6/0x670 net/ipv6/ip6_fib.c:960 Write of size 4 at addr 0000000000ffffb4 by task syz-executor.1/7649 CPU: 0 PID: 7649 Comm: syz-executor.1 Not tainted 5.1.0-rc6+ #183 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 kasan_report.cold+0x5/0x40 mm/kasan/report.c:321 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_write+0x14/0x20 mm/kasan/common.c:108 atomic_dec_and_test include/asm-generic/atomic-instrumented.h:747 [inline] fib6_info_release include/net/ip6_fib.h:294 [inline] fib6_info_release include/net/ip6_fib.h:292 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:927 [inline] fib6_purge_rt+0x4f6/0x670 net/ipv6/ip6_fib.c:960 fib6_del_route net/ipv6/ip6_fib.c:1813 [inline] fib6_del+0xac2/0x10a0 net/ipv6/ip6_fib.c:1844 fib6_clean_node+0x3a8/0x590 net/ipv6/ip6_fib.c:2006 fib6_walk_continue+0x495/0x900 net/ipv6/ip6_fib.c:1928 fib6_walk+0x9d/0x100 net/ipv6/ip6_fib.c:1976 fib6_clean_tree+0xe0/0x120 net/ipv6/ip6_fib.c:2055 __fib6_clean_all+0x118/0x2a0 net/ipv6/ip6_fib.c:2071 fib6_clean_all+0x2b/0x40 net/ipv6/ip6_fib.c:2082 rt6_sync_down_dev+0x134/0x150 net/ipv6/route.c:4057 rt6_disable_ip+0x27/0x5f0 net/ipv6/route.c:4062 addrconf_ifdown+0xa2/0x1220 net/ipv6/addrconf.c:3705 addrconf_notify+0x19a/0x2260 net/ipv6/addrconf.c:3630 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1753 call_netdevice_notifiers_extack net/core/dev.c:1765 [inline] call_netdevice_notifiers net/core/dev.c:1779 [inline] dev_close_many+0x33f/0x6f0 net/core/dev.c:1522 rollback_registered_many+0x43b/0xfd0 net/core/dev.c:8177 rollback_registered+0x109/0x1d0 net/core/dev.c:8242 unregister_netdevice_queue net/core/dev.c:9289 [inline] unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9282 unregister_netdevice include/linux/netdevice.h:2658 [inline] __tun_detach+0xd5b/0x1000 drivers/net/tun.c:727 tun_detach drivers/net/tun.c:744 [inline] tun_chr_close+0xe0/0x180 drivers/net/tun.c:3443 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:980 __do_sys_exit_group kernel/exit.c:991 [inline] __se_sys_exit_group kernel/exit.c:989 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:989 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffeafc2a6a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001c RCX: 0000000000458da9 RDX: 0000000000412a80 RSI: 0000000000a54ef0 RDI: 0000000000000043 RBP: 00000000004be552 R08: 000000000000000c R09: 000000000004c0d1 R10: 0000000002341940 R11: 0000000000000246 R12: 00000000ffffffff R13: 00007ffeafc2a7f0 R14: 000000000004c065 R15: 00007ffeafc2a800 Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected") Signed-off-by: Eric Dumazet Reported-by: syzbot Cc: David Ahern Reviewed-by: David Ahern Acked-by: Martin KaFai Lau Acked-by: Wei Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_fib.c | 4 +--- net/ipv6/route.c | 9 ++------- 2 files changed, 3 insertions(+), 10 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 6613d8dbb0e5..91247a6fc67f 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -921,9 +921,7 @@ static void fib6_drop_pcpu_from(struct fib6_info *f6i, if (pcpu_rt) { struct fib6_info *from; - from = rcu_dereference_protected(pcpu_rt->from, - lockdep_is_held(&table->tb6_lock)); - rcu_assign_pointer(pcpu_rt->from, NULL); + from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL); fib6_info_release(from); } } diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 9f132e471d7a..59c90bba048c 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -379,11 +379,8 @@ static void ip6_dst_destroy(struct dst_entry *dst) in6_dev_put(idev); } - rcu_read_lock(); - from = rcu_dereference(rt->from); - rcu_assign_pointer(rt->from, NULL); + from = xchg((__force struct fib6_info **)&rt->from, NULL); fib6_info_release(from); - rcu_read_unlock(); } static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, @@ -1288,9 +1285,7 @@ static void rt6_remove_exception(struct rt6_exception_bucket *bucket, /* purge completely the exception to allow releasing the held resources: * some [sk] cache may keep the dst around for unlimited time */ - from = rcu_dereference_protected(rt6_ex->rt6i->from, - lockdep_is_held(&rt6_exception_lock)); - rcu_assign_pointer(rt6_ex->rt6i->from, NULL); + from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL); fib6_info_release(from); dst_dev_put(&rt6_ex->rt6i->dst); -- cgit v1.2.3 From 787a77cccb1813de3bfd655a9d6338b1a0d4491f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 27 Apr 2019 16:49:06 -0700 Subject: ipv6/flowlabel: wait rcu grace period before put_pid() [ Upstream commit 6c0afef5fb0c27758f4d52b2210c61b6bd8b4470 ] syzbot was able to catch a use-after-free read in pid_nr_ns() [1] ip6fl_seq_show() seems to use RCU protection, dereferencing fl->owner.pid but fl_free() releases fl->owner.pid before rcu grace period is started. [1] BUG: KASAN: use-after-free in pid_nr_ns+0x128/0x140 kernel/pid.c:407 Read of size 4 at addr ffff888094012a04 by task syz-executor.0/18087 CPU: 0 PID: 18087 Comm: syz-executor.0 Not tainted 5.1.0-rc6+ #89 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 pid_nr_ns+0x128/0x140 kernel/pid.c:407 ip6fl_seq_show+0x2f8/0x4f0 net/ipv6/ip6_flowlabel.c:794 seq_read+0xad3/0x1130 fs/seq_file.c:268 proc_reg_read+0x1fe/0x2c0 fs/proc/inode.c:227 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x4a9/0x660 fs/read_write.c:922 vfs_readv+0xf0/0x160 fs/read_write.c:984 kernel_readv fs/splice.c:358 [inline] default_file_splice_read+0x475/0x890 fs/splice.c:413 do_splice_to+0x12a/0x190 fs/splice.c:876 splice_direct_to_actor+0x2d2/0x970 fs/splice.c:953 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062 do_sendfile+0x597/0xd00 fs/read_write.c:1443 __do_sys_sendfile64 fs/read_write.c:1498 [inline] __se_sys_sendfile64 fs/read_write.c:1490 [inline] __x64_sys_sendfile64+0x15a/0x220 fs/read_write.c:1490 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f300d24bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458da9 RDX: 00000000200000c0 RSI: 0000000000000008 RDI: 0000000000000007 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000005a R11: 0000000000000246 R12: 00007f300d24c6d4 R13: 00000000004c5fa3 R14: 00000000004da748 R15: 00000000ffffffff Allocated by task 17543: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3393 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3555 alloc_pid+0x55/0x8f0 kernel/pid.c:168 copy_process.part.0+0x3b08/0x7980 kernel/fork.c:1932 copy_process kernel/fork.c:1709 [inline] _do_fork+0x257/0xfd0 kernel/fork.c:2226 __do_sys_clone kernel/fork.c:2333 [inline] __se_sys_clone kernel/fork.c:2327 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2327 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7789: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3499 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3765 put_pid.part.0+0x111/0x150 kernel/pid.c:111 put_pid+0x20/0x30 kernel/pid.c:105 fl_free+0xbe/0xe0 net/ipv6/ip6_flowlabel.c:102 ip6_fl_gc+0x295/0x3e0 net/ipv6/ip6_flowlabel.c:152 call_timer_fn+0x190/0x720 kernel/time/timer.c:1325 expire_timers kernel/time/timer.c:1362 [inline] __run_timers kernel/time/timer.c:1681 [inline] __run_timers kernel/time/timer.c:1649 [inline] run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694 __do_softirq+0x266/0x95a kernel/softirq.c:293 The buggy address belongs to the object at ffff888094012a00 which belongs to the cache pid_2 of size 88 The buggy address is located 4 bytes inside of 88-byte region [ffff888094012a00, ffff888094012a58) The buggy address belongs to the page: page:ffffea0002500480 count:1 mapcount:0 mapping:ffff88809a483080 index:0xffff888094012980 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00018a3508 ffffea0002524a88 ffff88809a483080 raw: ffff888094012980 ffff888094012000 000000010000001b 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888094012900: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff888094012980: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc >ffff888094012a00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ^ ffff888094012a80: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff888094012b00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc Fixes: 4f82f45730c6 ("net ip6 flowlabel: Make owner a union of struct pid * and kuid_t") Signed-off-by: Eric Dumazet Cc: Eric W. Biederman Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_flowlabel.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c index cb54a8a3c273..23a525c0a9be 100644 --- a/net/ipv6/ip6_flowlabel.c +++ b/net/ipv6/ip6_flowlabel.c @@ -94,15 +94,21 @@ static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) return fl; } +static void fl_free_rcu(struct rcu_head *head) +{ + struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu); + + if (fl->share == IPV6_FL_S_PROCESS) + put_pid(fl->owner.pid); + kfree(fl->opt); + kfree(fl); +} + static void fl_free(struct ip6_flowlabel *fl) { - if (fl) { - if (fl->share == IPV6_FL_S_PROCESS) - put_pid(fl->owner.pid); - kfree(fl->opt); - kfree_rcu(fl, rcu); - } + if (fl) + call_rcu(&fl->rcu, fl_free_rcu); } static void fl_release(struct ip6_flowlabel *fl) -- cgit v1.2.3 From d1fa4f8784bb09e6e48765bd71eee7b702f088be Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Thu, 25 Apr 2019 12:06:54 -0400 Subject: ipv6: invert flowlabel sharing check in process and user mode [ Upstream commit 95c169251bf734aa555a1e8043e4d88ec97a04ec ] A request for a flowlabel fails in process or user exclusive mode must fail if the caller pid or uid does not match. Invert the test. Previously, the test was unsafe wrt PID recycling, but indeed tested for inequality: fl1->owner != fl->owner Fixes: 4f82f45730c68 ("net ip6 flowlabel: Make owner a union of struct pid* and kuid_t") Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_flowlabel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c index 23a525c0a9be..be5f3d7ceb96 100644 --- a/net/ipv6/ip6_flowlabel.c +++ b/net/ipv6/ip6_flowlabel.c @@ -639,9 +639,9 @@ recheck: if (fl1->share == IPV6_FL_S_EXCL || fl1->share != fl->share || ((fl1->share == IPV6_FL_S_PROCESS) && - (fl1->owner.pid == fl->owner.pid)) || + (fl1->owner.pid != fl->owner.pid)) || ((fl1->share == IPV6_FL_S_USER) && - uid_eq(fl1->owner.uid, fl->owner.uid))) + !uid_eq(fl1->owner.uid, fl->owner.uid))) goto release; err = -ENOMEM; -- cgit v1.2.3 From 92edcf205388b6bb211f0e56e91582f0cfa7c3f8 Mon Sep 17 00:00:00 2001 From: Stephen Suryaputra Date: Mon, 6 May 2019 15:00:01 -0400 Subject: vrf: sit mtu should not be updated when vrf netdev is the link [ Upstream commit ff6ab32bd4e073976e4d8797b4d514a172cfe6cb ] VRF netdev mtu isn't typically set and have an mtu of 65536. When the link of a tunnel is set, the tunnel mtu is changed from 1480 to the link mtu minus tunnel header. In the case of VRF netdev is the link, then the tunnel mtu becomes 65516. So, fix it by not setting the tunnel mtu in this case. Signed-off-by: Stephen Suryaputra Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/sit.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index b2109b74857d..971d60bf9640 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -1084,7 +1084,7 @@ static void ipip6_tunnel_bind_dev(struct net_device *dev) if (!tdev && tunnel->parms.link) tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); - if (tdev) { + if (tdev && !netif_is_l3_master(tdev)) { int t_hlen = tunnel->hlen + sizeof(struct iphdr); dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); -- cgit v1.2.3