kernel/linux.git/net/ipv6/addrconf.c, branch linux-4.13.y

ipv6: addrconf: increment ifp refcount before ipv6_del_addr()

2017-11-18T10:30:39+00:00

[ Upstream commit e669b86945478b3d90d2d87e3793a6eed06d332f ] In the (unlikely) event fixup_permanent_addr() returns a failure, addrconf_permanent_addr() calls ipv6_del_addr() without the mandatory call to in6_ifa_hold(), leading to a refcount error, spotted by syzkaller : WARNING: CPU: 1 PID: 3142 at lib/refcount.c:227 refcount_dec+0x4c/0x50 lib/refcount.c:227 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 3142 Comm: ip Not tainted 4.14.0-rc4-next-20171009+ #33 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 panic+0x1e4/0x41c kernel/panic.c:181 __warn+0x1c4/0x1e0 kernel/panic.c:544 report_bug+0x211/0x2d0 lib/bug.c:183 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:178 do_trap_no_signal arch/x86/kernel/traps.c:212 [inline] do_trap+0x260/0x390 arch/x86/kernel/traps.c:261 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:298 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:311 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905 RIP: 0010:refcount_dec+0x4c/0x50 lib/refcount.c:227 RSP: 0018:ffff8801ca49e680 EFLAGS: 00010286 RAX: 000000000000002c RBX: ffff8801d07cfcdc RCX: 0000000000000000 RDX: 000000000000002c RSI: 1ffff10039493c90 RDI: ffffed0039493cc4 RBP: ffff8801ca49e688 R08: ffff8801ca49dd70 R09: 0000000000000000 R10: ffff8801ca49df58 R11: 0000000000000000 R12: 1ffff10039493cd9 R13: ffff8801ca49e6e8 R14: ffff8801ca49e7e8 R15: ffff8801d07cfcdc __in6_ifa_put include/net/addrconf.h:369 [inline] ipv6_del_addr+0x42b/0xb60 net/ipv6/addrconf.c:1208 addrconf_permanent_addr net/ipv6/addrconf.c:3327 [inline] addrconf_notify+0x1c66/0x2190 net/ipv6/addrconf.c:3393 notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x32/0x60 net/core/dev.c:1697 call_netdevice_notifiers net/core/dev.c:1715 [inline] __dev_notify_flags+0x15d/0x430 net/core/dev.c:6843 dev_change_flags+0xf5/0x140 net/core/dev.c:6879 do_setlink+0xa1b/0x38e0 net/core/rtnetlink.c:2113 rtnl_newlink+0xf0d/0x1a40 net/core/rtnetlink.c:2661 rtnetlink_rcv_msg+0x733/0x1090 net/core/rtnetlink.c:4301 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2408 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4313 netlink_unicast_kernel net/netlink/af_netlink.c:1273 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1299 netlink_sendmsg+0xa4a/0xe70 net/netlink/af_netlink.c:1862 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 ___sys_sendmsg+0x75b/0x8a0 net/socket.c:2049 __sys_sendmsg+0xe5/0x210 net/socket.c:2083 SYSC_sendmsg net/socket.c:2094 [inline] SyS_sendmsg+0x2d/0x50 net/socket.c:2090 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x7fa9174d3320 RSP: 002b:00007ffe302ae9e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ffe302b2ae0 RCX: 00007fa9174d3320 RDX: 0000000000000000 RSI: 00007ffe302aea20 RDI: 0000000000000016 RBP: 0000000000000082 R08: 0000000000000000 R09: 000000000000000f R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe302b32a0 R13: 0000000000000000 R14: 00007ffe302b2ab8 R15: 00007ffe302b32b8 Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") Signed-off-by: Eric Dumazet Cc: David Ahern Acked-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv6: fix regression of no RTM_DELADDR sent after DAD failure

2017-10-12T09:56:04+00:00

[ Upstream commit 6819a14ecbe2e089e5c5bb74edecafdde2028a00 ] Commit f784ad3d79e5 ("ipv6: do not send RTM_DELADDR for tentative addresses") incorrectly assumes that no RTM_NEWADDR are sent for addresses in tentative state, as this does happen for the standard IPv6 use-case of DAD failure, see the call to ipv6_ifa_notify() in addconf_dad_stop(). So as a result of this change, no RTM_DELADDR is sent after DAD failure for a link-local when strict DAD (accept_dad=2) is configured, or on the next admin down in other cases. The absence of this notification breaks backwards compatibility and causes problems after DAD failure if this notification was being relied on. The solution is to allow RTM_DELADDR to still be sent after DAD failure. Fixes: f784ad3d79e5 ("ipv6: do not send RTM_DELADDR for tentative addresses") Signed-off-by: Mike Manning Cc: Mahesh Bandewar Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: fix sparse warning on rt6i_node

2017-08-28T22:34:40+00:00

Commit c5cff8561d2d adds rcu grace period before freeing fib6_node. This generates a new sparse warning on rt->rt6i_node related code: net/ipv6/route.c:1394:30: error: incompatible types in comparison expression (different address spaces) ./include/net/ip6_fib.h:187:14: error: incompatible types in comparison expression (different address spaces) This commit adds "__rcu" tag for rt6i_node and makes sure corresponding rcu API is used for it. After this fix, sparse no longer generates the above warning. Fixes: c5cff8561d2d ("ipv6: add rcu grace period before freeing fib6_node") Signed-off-by: Wei Wang Acked-by: Eric Dumazet Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller

net, ipv6: convert inet6_ifaddr.refcnt from atomic_t to refcount_t

2017-07-04T08:29:04+00:00

refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller

net, ipv6: convert inet6_dev.refcnt from atomic_t to refcount_t

2017-07-04T08:29:04+00:00

ipv6: dad: don't remove dynamic addresses if link is down

2017-07-03T08:53:51+00:00

Currently, when the link for $DEV is down, this command succeeds but the address is removed immediately by DAD (1): ip addr add 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800 In the same situation, this will succeed and not remove the address (2): ip addr add 1111::12/64 dev $DEV ip addr change 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800 The comment in addrconf_dad_begin() when !IF_READY makes it look like this is the intended behavior, but doesn't explain why: * If the device is not ready: * - keep it tentative if it is a permanent address. * - otherwise, kill it. We clearly cannot prevent userspace from doing (2), but we can make (1) work consistently with (2). addrconf_dad_stop() is only called in two cases: if DAD failed, or to skip DAD when the link is down. In that second case, the fix is to avoid deleting the address, like we already do for permanent addresses. Fixes: 3c21edbd1137 ("[IPV6]: Defer IPv6 device initialization until the link becomes ready.") Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-06-30T16:43:08+00:00

A set of overlapping changes in macvlan and the rocker driver, nothing serious. Signed-off-by: David S. Miller

ipv6: avoid unregistering inet6_dev for loopback

2017-06-22T17:21:44+00:00

The per netns loopback_dev->ip6_ptr is unregistered and set to NULL when its mtu is set to smaller than IPV6_MIN_MTU, this leads to that we could set rt->rt6i_idev NULL after a rt6_uncached_list_flush_dev() and then crash after another call. In this case we should just bring its inet6_dev down, rather than unregistering it, at least prior to commit 176c39af29bc ("netns: fix addrconf_ifdown kernel panic") we always override the case for loopback. Thanks a lot to Andrey for finding a reliable reproducer. Fixes: 176c39af29bc ("netns: fix addrconf_ifdown kernel panic") Reported-by: Andrey Konovalov Cc: Andrey Konovalov Cc: Daniel Lezcano Cc: David Ahern Signed-off-by: Cong Wang Acked-by: David Ahern Tested-by: Andrey Konovalov Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-06-21T21:35:22+00:00

Two entries being added at the same time to the IFLA policy table, whilst parallel bug fixes to decnet routing dst handling overlapping with the dst gc removal in net-next. Signed-off-by: David S. Miller

ipv6: call dst_hold_safe() properly

2017-06-18T02:54:00+00:00

Similar as ipv4, ipv6 path also needs to call dst_hold_safe() when necessary to avoid double free issue on the dst. Signed-off-by: Wei Wang Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller