commit bb0de3131f4c60a9bf976681e0fe4d1e55c7a821 upstream.
The sockmap code currently ignores the value of attach_bpf_fd when
detaching a program. This is contrary to the usual behaviour of
checking that attach_bpf_fd represents the currently attached
program.
Ensure that attach_bpf_fd is indeed the currently attached
program. It turns out that all sockmap selftests already do this,
which indicates that this is unlikely to cause breakage.
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-5-lmb@cloudflare.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9b2b09717e1812e450782a43ca0c2790651cf380 upstream.
Using BPF_PROG_ATTACH on a sockmap program currently understands no
flags or replace_bpf_fd, but accepts any value. Return EINVAL instead.
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-4-lmb@cloudflare.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ad0f75e5f57ccbceec13274e1e242f2b5a6397ed ]
When we clone a socket in sk_clone_lock(), its sk_cgrp_data is
copied, so the cgroup refcnt must be taken too. And, unlike the
sk_alloc() path, sock_update_netprioidx() is not called here.
Therefore, it is safe and necessary to grab the cgroup refcnt
even when cgroup_sk_alloc is disabled.
sk_clone_lock() is in BH context anyway, the in_interrupt()
would terminate this function if called there. And for sk_alloc()
skcd->val is always zero. So it's safe to factor out the code
to make it more readable.
The global variable 'cgroup_sk_alloc_disabled' is used to determine
whether to take these reference counts. It is impossible to make
the reference counting correct unless we save this bit of information
in skcd->val. So, add a new bit there to record whether the socket
has already taken the reference counts. This obviously relies on
kmalloc() to align cgroup pointers to at least 4 bytes,
ARCH_KMALLOC_MINALIGN is certainly larger than that.
This bug seems to be introduced since the beginning, commit
d979a39d7242 ("cgroup: duplicate cgroup reference when cloning sockets")
tried to fix it but not compeletely. It seems not easy to trigger until
the recent commit 090e28b229af
("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged.
Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Cameron Berkenpas <cam@neo-zeon.de>
Reported-by: Peter Geis <pgwipeout@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reported-by: Daniël Sonck <dsonck92@gmail.com>
Reported-by: Zhang Qiang <qiang.zhang@windriver.com>
Tested-by: Cameron Berkenpas <cam@neo-zeon.de>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d7bf2ebebc2bd61ab95e2a8e33541ef282f303d4 ]
There are a couple of places in net/sched/ that check skb->protocol and act
on the value there. However, in the presence of VLAN tags, the value stored
in skb->protocol can be inconsistent based on whether VLAN acceleration is
enabled. The commit quoted in the Fixes tag below fixed the users of
skb->protocol to use a helper that will always see the VLAN ethertype.
However, most of the callers don't actually handle the VLAN ethertype, but
expect to find the IP header type in the protocol field. This means that
things like changing the ECN field, or parsing diffserv values, stops
working if there's a VLAN tag, or if there are multiple nested VLAN
tags (QinQ).
To fix this, change the helper to take an argument that indicates whether
the caller wants to skip the VLAN tags or not. When skipping VLAN tags, we
make sure to skip all of them, so behaviour is consistent even in QinQ
mode.
To make the helper usable from the ECN code, move it to if_vlan.h instead
of pkt_sched.h.
v3:
- Remove empty lines
- Move vlan variable definitions inside loop in skb_protocol()
- Also use skb_protocol() helper in IP{,6}_ECN_decapsulate() and
bpf_skb_ecn_set_ce()
v2:
- Use eth_type_vlan() helper in skb_protocol()
- Also fix code that reads skb->protocol directly
- Change a couple of 'if/else if' statements to switch constructs to avoid
calling the helper twice
Reported-by: Ilya Ponetayev <i.ponetaev@ndmsystems.com>
Fixes: d8b9605d2697 ("net: sched: fix skb->protocol use in case of accelerated vlan path")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63960260457a02af2a6cb35d75e6bdb17299c882 upstream.
When evaluating access control over kallsyms visibility, credentials at
open() time need to be used, not the "current" creds (though in BPF's
case, this has likely always been the same). Plumb access to associated
file->f_cred down through bpf_dump_raw_ok() and its callers now that
kallsysm_show_value() has been refactored to take struct cred.
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 7105e828c087 ("bpf: allow for correlation of maps and helpers in dump")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8025751d4d55a2f32be6bdf825b6a80c299875f5 ]
If an ingress verdict program specifies message sizes greater than
skb->len and there is an ENOMEM error due to memory pressure we
may call the rcv_msg handler outside the strp_data_ready() caller
context. This is because on an ENOMEM error the strparser will
retry from a workqueue. The caller currently protects the use of
psock by calling the strp_data_ready() inside a rcu_read_lock/unlock
block.
But, in above workqueue error case the psock is accessed outside
the read_lock/unlock block of the caller. So instead of using
psock directly we must do a look up against the sk again to
ensure the psock is available.
There is an an ugly piece here where we must handle
the case where we paused the strp and removed the psock. On
psock removal we first pause the strparser and then remove
the psock. If the strparser is paused while an skb is
scheduled on the workqueue the skb will be dropped on the
flow and kfree_skb() is called. If the workqueue manages
to get called before we pause the strparser but runs the rcvmsg
callback after the psock is removed we will hit the unlikely
case where we run the sockmap rcvmsg handler but do not have
a psock. For now we will follow strparser logic and drop the
skb on the floor with skb_kfree(). This is ugly because the
data is dropped. To date this has not caused problems in practice
because either the application controlling the sockmap is
coordinating with the datapath so that skbs are "flushed"
before removal or we simply wait for the sock to be closed before
removing it.
This patch fixes the describe RCU bug and dropping the skb doesn't
make things worse. Future patches will improve this by allowing
the normal case where skbs are not merged to skip the strparser
altogether. In practice many (most?) use cases have no need to
merge skbs so its both a code complexity hit as seen above and
a performance issue. For example, in the Cilium case we always
set the strparser up to return sbks 1:1 without any merging and
have avoided above issues.
Fixes: e91de6afa81c1 ("bpf: Fix running sk_skb program types with ktls")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/159312679888.18340.15248924071966273998.stgit@john-XPS-13-9370
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 93dd5f185916b05e931cffae636596f21f98546e ]
There are two paths to generate the below RCU splat the first and
most obvious is the result of the BPF verdict program issuing a
redirect on a TLS socket (This is the splat shown below). Unlike
the non-TLS case the caller of the *strp_read() hooks does not
wrap the call in a rcu_read_lock/unlock. Then if the BPF program
issues a redirect action we hit the RCU splat.
However, in the non-TLS socket case the splat appears to be
relatively rare, because the skmsg caller into the strp_data_ready()
is wrapped in a rcu_read_lock/unlock. Shown here,
static void sk_psock_strp_data_ready(struct sock *sk)
{
struct sk_psock *psock;
rcu_read_lock();
psock = sk_psock(sk);
if (likely(psock)) {
if (tls_sw_has_ctx_rx(sk)) {
psock->parser.saved_data_ready(sk);
} else {
write_lock_bh(&sk->sk_callback_lock);
strp_data_ready(&psock->parser.strp);
write_unlock_bh(&sk->sk_callback_lock);
}
}
rcu_read_unlock();
}
If the above was the only way to run the verdict program we
would be safe. But, there is a case where the strparser may throw an
ENOMEM error while parsing the skb. This is a result of a failed
skb_clone, or alloc_skb_for_msg while building a new merged skb when
the msg length needed spans multiple skbs. This will in turn put the
skb on the strp_wrk workqueue in the strparser code. The skb will
later be dequeued and verdict programs run, but now from a
different context without the rcu_read_lock()/unlock() critical
section in sk_psock_strp_data_ready() shown above. In practice
I have not seen this yet, because as far as I know most users of the
verdict programs are also only working on single skbs. In this case no
merge happens which could trigger the above ENOMEM errors. In addition
the system would need to be under memory pressure. For example, we
can't hit the above case in selftests because we missed having tests
to merge skbs. (Added in later patch)
To fix the below splat extend the rcu_read_lock/unnlock block to
include the call to sk_psock_tls_verdict_apply(). This will fix both
TLS redirect case and non-TLS redirect+error case. Also remove
psock from the sk_psock_tls_verdict_apply() function signature its
not used there.
[ 1095.937597] WARNING: suspicious RCU usage
[ 1095.940964] 5.7.0-rc7-02911-g463bac5f1ca79 #1 Tainted: G W
[ 1095.944363] -----------------------------
[ 1095.947384] include/linux/skmsg.h:284 suspicious rcu_dereference_check() usage!
[ 1095.950866]
[ 1095.950866] other info that might help us debug this:
[ 1095.950866]
[ 1095.957146]
[ 1095.957146] rcu_scheduler_active = 2, debug_locks = 1
[ 1095.961482] 1 lock held by test_sockmap/15970:
[ 1095.964501] #0: ffff9ea6b25de660 (sk_lock-AF_INET){+.+.}-{0:0}, at: tls_sw_recvmsg+0x13a/0x840 [tls]
[ 1095.968568]
[ 1095.968568] stack backtrace:
[ 1095.975001] CPU: 1 PID: 15970 Comm: test_sockmap Tainted: G W 5.7.0-rc7-02911-g463bac5f1ca79 #1
[ 1095.977883] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[ 1095.980519] Call Trace:
[ 1095.982191] dump_stack+0x8f/0xd0
[ 1095.984040] sk_psock_skb_redirect+0xa6/0xf0
[ 1095.986073] sk_psock_tls_strp_read+0x1d8/0x250
[ 1095.988095] tls_sw_recvmsg+0x714/0x840 [tls]
v2: Improve commit message to identify non-TLS redirect plus error case
condition as well as more common TLS case. In the process I decided
doing the rcu_read_unlock followed by the lock/unlock inside branches
was unnecessarily complex. We can just extend the current rcu block
and get the same effeective without the shuffling and branching.
Thanks Martin!
Fixes: e91de6afa81c1 ("bpf: Fix running sk_skb program types with ktls")
Reported-by: Jakub Sitnicki <jakub@cloudflare.com>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/159312677907.18340.11064813152758406626.stgit@john-XPS-13-9370
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bb986a50421a11bf31a81afb15b9b8f45a4a3a11 ]
The seg6_validate_srh() is used to validate SRH for three cases:
case1: SRH of data-plane SRv6 packets to be processed by the Linux kernel.
Case2: SRH of the netlink message received from user-space (iproute2)
Case3: SRH injected into packets through setsockopt
In case1, the SRH can be encoded in the Reduced way (i.e., first SID is
carried in DA only and not represented as SID in the SRH) and the
seg6_validate_srh() now handles this case correctly.
In case2 and case3, the SRH shouldn’t be encoded in the Reduced way
otherwise we lose the first segment (i.e., the first hop).
The current implementation of the seg6_validate_srh() allow SRH of case2
and case3 to be encoded in the Reduced way. This leads a slab-out-of-bounds
problem.
This patch verifies SRH of case1, case2 and case3. Allowing case1 to be
reduced while preventing SRH of case2 and case3 from being reduced .
Reported-by: syzbot+e8c028b62439eac42073@syzkaller.appspotmail.com
Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 0cb7498f234e ("seg6: fix SRH processing to comply with RFC8754")
Signed-off-by: Ahmed Abdelsalam <ahabdels@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0ad6f6e767ec2f613418cbc7ebe5ec4c35af540c ]
Back in commit f60e5990d9c1 ("ipv6: protect skb->sk accesses
from recursive dereference inside the stack") Hannes added code
so that IPv6 stack would not trust skb->sk for typical cases
where packet goes through 'standard' xmit path (__dev_queue_xmit())
Alas af_packet had a dev_direct_xmit() path that was not
dealing yet with xmit_recursion level.
Also change sk_mc_loop() to dump a stack once only.
Without this patch, syzbot was able to trigger :
[1]
[ 153.567378] WARNING: CPU: 7 PID: 11273 at net/core/sock.c:721 sk_mc_loop+0x51/0x70
[ 153.567378] Modules linked in: nfnetlink ip6table_raw ip6table_filter iptable_raw iptable_nat nf_nat nf_conntrack nf_defrag_ipv4 nf_defrag_ipv6 iptable_filter macsec macvtap tap macvlan 8021q hsr wireguard libblake2s blake2s_x86_64 libblake2s_generic udp_tunnel ip6_udp_tunnel libchacha20poly1305 poly1305_x86_64 chacha_x86_64 libchacha curve25519_x86_64 libcurve25519_generic netdevsim batman_adv dummy team bridge stp llc w1_therm wire i2c_mux_pca954x i2c_mux cdc_acm ehci_pci ehci_hcd mlx4_en mlx4_ib ib_uverbs ib_core mlx4_core
[ 153.567386] CPU: 7 PID: 11273 Comm: b159172088 Not tainted 5.8.0-smp-DEV #273
[ 153.567387] RIP: 0010:sk_mc_loop+0x51/0x70
[ 153.567388] Code: 66 83 f8 0a 75 24 0f b6 4f 12 b8 01 00 00 00 31 d2 d3 e0 a9 bf ef ff ff 74 07 48 8b 97 f0 02 00 00 0f b6 42 3a 83 e0 01 5d c3 <0f> 0b b8 01 00 00 00 5d c3 0f b6 87 18 03 00 00 5d c0 e8 04 83 e0
[ 153.567388] RSP: 0018:ffff95c69bb93990 EFLAGS: 00010212
[ 153.567388] RAX: 0000000000000011 RBX: ffff95c6e0ee3e00 RCX: 0000000000000007
[ 153.567389] RDX: ffff95c69ae50000 RSI: ffff95c6c30c3000 RDI: ffff95c6c30c3000
[ 153.567389] RBP: ffff95c69bb93990 R08: ffff95c69a77f000 R09: 0000000000000008
[ 153.567389] R10: 0000000000000040 R11: 00003e0e00026128 R12: ffff95c6c30c3000
[ 153.567390] R13: ffff95c6cc4fd500 R14: ffff95c6f84500c0 R15: ffff95c69aa13c00
[ 153.567390] FS: 00007fdc3a283700(0000) GS:ffff95c6ff9c0000(0000) knlGS:0000000000000000
[ 153.567390] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 153.567391] CR2: 00007ffee758e890 CR3: 0000001f9ba20003 CR4: 00000000001606e0
[ 153.567391] Call Trace:
[ 153.567391] ip6_finish_output2+0x34e/0x550
[ 153.567391] __ip6_finish_output+0xe7/0x110
[ 153.567391] ip6_finish_output+0x2d/0xb0
[ 153.567392] ip6_output+0x77/0x120
[ 153.567392] ? __ip6_finish_output+0x110/0x110
[ 153.567392] ip6_local_out+0x3d/0x50
[ 153.567392] ipvlan_queue_xmit+0x56c/0x5e0
[ 153.567393] ? ksize+0x19/0x30
[ 153.567393] ipvlan_start_xmit+0x18/0x50
[ 153.567393] dev_direct_xmit+0xf3/0x1c0
[ 153.567393] packet_direct_xmit+0x69/0xa0
[ 153.567394] packet_sendmsg+0xbf0/0x19b0
[ 153.567394] ? plist_del+0x62/0xb0
[ 153.567394] sock_sendmsg+0x65/0x70
[ 153.567394] sock_write_iter+0x93/0xf0
[ 153.567394] new_sync_write+0x18e/0x1a0
[ 153.567395] __vfs_write+0x29/0x40
[ 153.567395] vfs_write+0xb9/0x1b0
[ 153.567395] ksys_write+0xb1/0xe0
[ 153.567395] __x64_sys_write+0x1a/0x20
[ 153.567395] do_syscall_64+0x43/0x70
[ 153.567396] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 153.567396] RIP: 0033:0x453549
[ 153.567396] Code: Bad RIP value.
[ 153.567396] RSP: 002b:00007fdc3a282cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 153.567397] RAX: ffffffffffffffda RBX: 00000000004d32d0 RCX: 0000000000453549
[ 153.567397] RDX: 0000000000000020 RSI: 0000000020000300 RDI: 0000000000000003
[ 153.567398] RBP: 00000000004d32d8 R08: 0000000000000000 R09: 0000000000000000
[ 153.567398] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d32dc
[ 153.567398] R13: 00007ffee742260f R14: 00007fdc3a282dc0 R15: 00007fdc3a283700
[ 153.567399] ---[ end trace c1d5ae2b1059ec62 ]---
f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 814152a89ed52c722ab92e9fbabcac3cb8a39245 ]
I got a memleak report when doing some fuzz test:
unreferenced object 0xffff888112584000 (size 13599):
comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
hex dump (first 32 bytes):
74 61 70 30 00 00 00 00 00 00 00 00 00 00 00 00 tap0............
00 ee d9 19 81 88 ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000002f60ba65>] __kmalloc_node+0x309/0x3a0
[<0000000075b211ec>] kvmalloc_node+0x7f/0xc0
[<00000000d3a97396>] alloc_netdev_mqs+0x76/0xfc0
[<00000000609c3655>] __tun_chr_ioctl+0x1456/0x3d70
[<000000001127ca24>] ksys_ioctl+0xe5/0x130
[<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
[<00000000e1023498>] do_syscall_64+0x56/0xa0
[<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
unreferenced object 0xffff888111845cc0 (size 8):
comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
hex dump (first 8 bytes):
74 61 70 30 00 88 ff ff tap0....
backtrace:
[<000000004c159777>] kstrdup+0x35/0x70
[<00000000d8b496ad>] kstrdup_const+0x3d/0x50
[<00000000494e884a>] kvasprintf_const+0xf1/0x180
[<0000000097880a2b>] kobject_set_name_vargs+0x56/0x140
[<000000008fbdfc7b>] dev_set_name+0xab/0xe0
[<000000005b99e3b4>] netdev_register_kobject+0xc0/0x390
[<00000000602704fe>] register_netdevice+0xb61/0x1250
[<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70
[<000000001127ca24>] ksys_ioctl+0xe5/0x130
[<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
[<00000000e1023498>] do_syscall_64+0x56/0xa0
[<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
unreferenced object 0xffff88811886d800 (size 512):
comm "ip", pid 3048, jiffies 4294911734 (age 343.491s)
hex dump (first 32 bytes):
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
ff ff ff ff ff ff ff ff c0 66 3d a3 ff ff ff ff .........f=.....
backtrace:
[<0000000050315800>] device_add+0x61e/0x1950
[<0000000021008dfb>] netdev_register_kobject+0x17e/0x390
[<00000000602704fe>] register_netdevice+0xb61/0x1250
[<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70
[<000000001127ca24>] ksys_ioctl+0xe5/0x130
[<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0
[<00000000e1023498>] do_syscall_64+0x56/0xa0
[<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
If call_netdevice_notifiers() failed, then rollback_registered()
calls netdev_unregister_kobject() which holds the kobject. The
reference cannot be put because the netdev won't be add to todo
list, so it will leads a memleak, we need put the reference to
avoid memleak.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>