Eric Dumazet
d360c6cf66
ipv6: fib6_rules: avoid possible NULL dereference in fib6_rule_action()
...
[ Upstream commit d101291b2681e5ab938554e3e323f7a7ee33e3aa ]
syzbot is able to trigger the following crash [1],
caused by unsafe ip6_dst_idev() use.
Indeed ip6_dst_idev() can return NULL, and must always be checked.
[1]
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1 ] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 31648 Comm: syz-executor.0 Not tainted 6.9.0-rc4-next-20240417-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:__fib6_rule_action net/ipv6/fib6_rules.c:237 [inline]
RIP: 0010:fib6_rule_action+0x241/0x7b0 net/ipv6/fib6_rules.c:267
Code: 02 00 00 49 8d 9f d8 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 f9 32 bf f7 48 8b 1b 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 e0 32 bf f7 4c 8b 03 48 89 ef 4c
RSP: 0018:ffffc9000fc1f2f0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1a772f98c8186700
RDX: 0000000000000003 RSI: ffffffff8bcac4e0 RDI: ffffffff8c1f9760
RBP: ffff8880673fb980 R08: ffffffff8fac15ef R09: 1ffffffff1f582bd
R10: dffffc0000000000 R11: fffffbfff1f582be R12: dffffc0000000000
R13: 0000000000000080 R14: ffff888076509000 R15: ffff88807a029a00
FS: 00007f55e82ca6c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31d23000 CR3: 0000000022b66000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
fib_rules_lookup+0x62c/0xdb0 net/core/fib_rules.c:317
fib6_rule_lookup+0x1fd/0x790 net/ipv6/fib6_rules.c:108
ip6_route_output_flags_noref net/ipv6/route.c:2637 [inline]
ip6_route_output_flags+0x38e/0x610 net/ipv6/route.c:2649
ip6_route_output include/net/ip6_route.h:93 [inline]
ip6_dst_lookup_tail+0x189/0x11a0 net/ipv6/ip6_output.c:1120
ip6_dst_lookup_flow+0xb9/0x180 net/ipv6/ip6_output.c:1250
sctp_v6_get_dst+0x792/0x1e20 net/sctp/ipv6.c:326
sctp_transport_route+0x12c/0x2e0 net/sctp/transport.c:455
sctp_assoc_add_peer+0x614/0x15c0 net/sctp/associola.c:662
sctp_connect_new_asoc+0x31d/0x6c0 net/sctp/socket.c:1099
__sctp_connect+0x66d/0xe30 net/sctp/socket.c:1197
sctp_connect net/sctp/socket.c:4819 [inline]
sctp_inet_connect+0x149/0x1f0 net/sctp/socket.c:4834
__sys_connect_file net/socket.c:2048 [inline]
__sys_connect+0x2df/0x310 net/socket.c:2065
__do_sys_connect net/socket.c:2075 [inline]
__se_sys_connect net/socket.c:2072 [inline]
__x64_sys_connect+0x7a/0x90 net/socket.c:2072
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Fixes: 5e5f3f0f8013 ("[IPV6] ADDRCONF: Convert ipv6_get_saddr() to ipv6_dev_get_saddr().")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240507163145.835254-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 11:32:46 +01:00
Shiming Cheng
3fcb9ee2d1
ipv6: fib6_rules: flush route cache when rule is changed
...
[ Upstream commit c4386ab4f6c600f75fdfd21143f89bac3e625d0d ]
When rule policy is changed, ipv6 socket cache is not refreshed.
The sock's skb still uses a outdated route cache and was sent to
a wrong interface.
To avoid this error we should update fib node's version when
rule is changed. Then skb's route will be reroute checked as
route cache version is already different with fib node version.
The route cache is refreshed to match the latest rule.
Fixes: 101367c2f8c4 ("[IPV6]: Policy Routing Rules")
Signed-off-by: Shiming Cheng <shiming.cheng@mediatek.com>
Signed-off-by: Lena Wang <lena.wang@mediatek.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 08:44:49 +01:00
