linux-stable.git/net/ipv6, branch v3.16.75 Linux kernel stable tree ipv6: flowlabel: fl6_sock_lookup() must use atomic_inc_not_zero 2019-10-05T15:19:55+00:00 Eric Dumazet edumazet@google.com 2019-06-06T21:32:34+00:00 c03cd5758090d132a168a83984bc69e66350e59b commit 65a3c497c0e965a552008db8bc2653f62bc925a1 upstream. Before taking a refcount, make sure the object is not already scheduled for deletion. Same fix is needed in ipv6_flowlabel_opt() Fixes: 18367681a10b ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 65a3c497c0e965a552008db8bc2653f62bc925a1 upstream.

Before taking a refcount, make sure the object is not already
scheduled for deletion.

Same fix is needed in ipv6_flowlabel_opt()

Fixes: 18367681a10b ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
inet: switch IP ID generator to siphash 2019-08-13T11:39:32+00:00 Eric Dumazet edumazet@google.com 2019-03-27T19:40:33+00:00 9ebeec41ed3f52fd94267f25f8b9bf3f4cbf1e4e commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream. According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream.

According to Amit Klein and Benny Pinkas, IP ID generation is too weak
and might be used by attackers.

Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix())
having 64bit key and Jenkins hash is risky.

It is time to switch to siphash and its 128bit keys.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: hash net ptr into fragmentation bucket selection 2019-08-13T11:39:31+00:00 Hannes Frederic Sowa hannes@stressinduktion.org 2015-03-25T16:07:45+00:00 6caabe4c7dab391fcd7ee36e6cba75697b9e7871 commit 5a352dd0a3aac03b443c94828dfd7144261c8636 upstream. As namespaces are sometimes used with overlapping ip address ranges, we should also use the namespace as input to the hash to select the ip fragmentation counter bucket. Cc: Eric Dumazet <edumazet@google.com> Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 5a352dd0a3aac03b443c94828dfd7144261c8636 upstream.

As namespaces are sometimes used with overlapping ip address ranges,
we should also use the namespace as input to the hash to select the ip
fragmentation counter bucket.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: call ipv6_proxy_select_ident instead of ipv6_select_ident in udp6_ufo_fragment 2019-08-13T11:39:30+00:00 Sabrina Dubroca sd@queasysnail.net 2015-03-19T10:22:32+00:00 66d7c265f2b1358c389b825fd017eb82ebbba229 commit 8e199dfd82ee097b522b00344af6448715d8ee0c upstream. Matt Grant reported frequent crashes in ipv6_select_ident when udp6_ufo_fragment is called from openvswitch on a skb that doesn't have a dst_entry set. ipv6_proxy_select_ident generates the frag_id without using the dst associated with the skb. This approach was suggested by Vladislav Yasevich. Fixes: 0508c07f5e0c ("ipv6: Select fragment id during UFO segmentation if not set.") Cc: Vladislav Yasevich <vyasevic@redhat.com> Reported-by: Matt Grant <matt@mattgrant.net.nz> Tested-by: Matt Grant <matt@mattgrant.net.nz> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 8e199dfd82ee097b522b00344af6448715d8ee0c upstream.

Matt Grant reported frequent crashes in ipv6_select_ident when
udp6_ufo_fragment is called from openvswitch on a skb that doesn't
have a dst_entry set.

ipv6_proxy_select_ident generates the frag_id without using the dst
associated with the skb.  This approach was suggested by Vladislav
Yasevich.

Fixes: 0508c07f5e0c ("ipv6: Select fragment id during UFO segmentation if not set.")
Cc: Vladislav Yasevich <vyasevic@redhat.com>
Reported-by: Matt Grant <matt@mattgrant.net.nz>
Tested-by: Matt Grant <matt@mattgrant.net.nz>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: Make __ipv6_select_ident static 2019-08-13T11:39:30+00:00 Vlad Yasevich vyasevich@gmail.com 2015-02-09T14:38:21+00:00 dbac56343705df2d24e3588a6ef421d386eda7be commit 8381eacf5c3b35cf7755f4bc521c4d56d24c1cd9 upstream. Make __ipv6_select_ident() static as it isn't used outside the file. Fixes: 0508c07f5e0c9 (ipv6: Select fragment id during UFO segmentation if not set.) Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 8381eacf5c3b35cf7755f4bc521c4d56d24c1cd9 upstream.

Make __ipv6_select_ident() static as it isn't used outside
the file.

Fixes: 0508c07f5e0c9 (ipv6: Select fragment id during UFO segmentation if not set.)
Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: Fix fragment id assignment on LE arches. 2019-08-13T11:39:29+00:00 Vlad Yasevich vyasevich@gmail.com 2015-02-09T14:38:20+00:00 40abf106876af3fef2aea449d1099cd01c5deb19 commit 51f30770e50eb787200f30a79105e2615b379334 upstream. Recent commit: 0508c07f5e0c94f38afd5434e8b2a55b84553077 Author: Vlad Yasevich <vyasevich@gmail.com> Date: Tue Feb 3 16:36:15 2015 -0500 ipv6: Select fragment id during UFO segmentation if not set. Introduced a bug on LE in how ipv6 fragment id is assigned. This was cought by nightly sparce check: Resolve the following sparce error: net/ipv6/output_core.c:57:38: sparse: incorrect type in assignment (different base types) net/ipv6/output_core.c:57:38: expected restricted __be32 [usertype] ip6_frag_id net/ipv6/output_core.c:57:38: got unsigned int [unsigned] [assigned] [usertype] id Fixes: 0508c07f5e0c9 (ipv6: Select fragment id during UFO segmentation if not set.) Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 51f30770e50eb787200f30a79105e2615b379334 upstream.

Recent commit:
0508c07f5e0c94f38afd5434e8b2a55b84553077
Author: Vlad Yasevich <vyasevich@gmail.com>
Date:   Tue Feb 3 16:36:15 2015 -0500

    ipv6: Select fragment id during UFO segmentation if not set.

Introduced a bug on LE in how ipv6 fragment id is assigned.
This was cought by nightly sparce check:

Resolve the following sparce error:
 net/ipv6/output_core.c:57:38: sparse: incorrect type in assignment
 (different base types)
   net/ipv6/output_core.c:57:38:    expected restricted __be32
[usertype] ip6_frag_id
   net/ipv6/output_core.c:57:38:    got unsigned int [unsigned]
[assigned] [usertype] id

Fixes: 0508c07f5e0c9 (ipv6: Select fragment id during UFO segmentation if not set.)
Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: Select fragment id during UFO segmentation if not set. 2019-08-13T11:39:29+00:00 Vlad Yasevich vyasevich@gmail.com 2015-02-03T21:36:15+00:00 2e095ca0c58515774e6dd45f1f698682c073237f commit 0508c07f5e0c94f38afd5434e8b2a55b84553077 upstream. If the IPv6 fragment id has not been set and we perform fragmentation due to UFO, select a new fragment id. We now consider a fragment id of 0 as unset and if id selection process returns 0 (after all the pertrubations), we set it to 0x80000000, thus giving us ample space not to create collisions with the next packet we may have to fragment. When doing UFO integrity checking, we also select the fragment id if it has not be set yet. This is stored into the skb_shinfo() thus allowing UFO to function correclty. This patch also removes duplicate fragment id generation code and moves ipv6_select_ident() into the header as it may be used during GSO. Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 0508c07f5e0c94f38afd5434e8b2a55b84553077 upstream.

If the IPv6 fragment id has not been set and we perform
fragmentation due to UFO, select a new fragment id.
We now consider a fragment id of 0 as unset and if id selection
process returns 0 (after all the pertrubations), we set it to
0x80000000, thus giving us ample space not to create collisions
with the next packet we may have to fragment.

When doing UFO integrity checking, we also select the
fragment id if it has not be set yet.   This is stored into
the skb_shinfo() thus allowing UFO to function correclty.

This patch also removes duplicate fragment id generation code
and moves ipv6_select_ident() into the header as it may be
used during GSO.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Revert "inet: update the IP ID generation algorithm to higher standards." 2019-08-13T11:39:28+00:00 Ben Hutchings ben@decadent.org.uk 2019-08-09T19:09:49+00:00 05f4b670242e2b27c95d6eca88ac1fbf79c27a56 This reverts commit 8b197d3ce585d6777197e0633d71e5af7d98cb35, which was a stable-specific improvement to IP ID selection. I will apply the upstream changes instead. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
This reverts commit 8b197d3ce585d6777197e0633d71e5af7d98cb35, which
was a stable-specific improvement to IP ID selection.  I will apply
the upstream changes instead.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6/flowlabel: wait rcu grace period before put_pid() 2019-08-13T11:39:18+00:00 Eric Dumazet edumazet@google.com 2019-04-27T23:49:06+00:00 53b7d31459a52b1c95e2eede00c1fb0341bda4ab commit 6c0afef5fb0c27758f4d52b2210c61b6bd8b4470 upstream. 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 <edumazet@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: Move the release_net() call too, not that it does anything.] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 6c0afef5fb0c27758f4d52b2210c61b6bd8b4470 upstream.

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 <edumazet@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: Move the release_net() call too, not that it does
 anything.]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: invert flowlabel sharing check in process and user mode 2019-08-13T11:39:18+00:00 Willem de Bruijn willemb@google.com 2019-04-25T16:06:54+00:00 9fd1512321314137f0e7c1366a1041ac6774fb8e commit 95c169251bf734aa555a1e8043e4d88ec97a04ec upstream. 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 <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 95c169251bf734aa555a1e8043e4d88ec97a04ec upstream.

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 <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>