pppol2tp_ioctl() read sock->sk->sk_user_data directly without any
locks or reference counting. If a controllable sleep was induced during
copy_from_user() (e.g. via a userfaultfd page fault sleep), a concurrent
socket close could trigger pppol2tp_session_close() asynchronously. This
frees the l2tp_session structure via the l2tp_session_del_work workqueue.
Upon resuming, the ioctl thread dereferences the stale session pointer,
resulting in a Use-After-Free (UAF).
Fix this by securely fetching the session reference using the RCU-safe,
refcounted helper pppol2tp_sock_to_session(sk) on entry. This locks the
session's refcount across the sleep. We structured the function to exit
via standard err breaks, guaranteeing that l2tp_session_put() is cleanly
called on all return paths to drop the reference.
To preserve existing behavior we validate the session and its magic
signature only for the specific L2TP commands that require it. This
ensures that generic/unknown ioctls called on an unconnected socket
still return -ENOIOCTLCMD and correctly fall back to generic handlers
(e.g. in sock_do_ioctl()).
Signed-off-by: Lee Jones <lee@kernel.org>
Fixes: fd558d186d ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Link: https://patch.msgid.link/20260527133630.2120612-1-lee@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A reader in l2tp_session_get_by_ifname() can return a pointer to a
session whose refcount has reached zero. The getter takes its
reference with plain refcount_inc(), but every other session getter
in the same file (l2tp_v2_session_get, l2tp_v3_session_get, and the
corresponding _get_next variants) uses refcount_inc_not_zero()
because the IDR/RCU lookup can race with refcount_dec_and_test() ->
l2tp_session_free() -> kfree_rcu(). The ifname getter is the only
outlier; the inconsistency was raised on-list after 979c017803
("l2tp: use list_del_rcu in l2tp_session_unhash").
A reader inside rcu_read_lock_bh() that matches session->ifname can
be preempted between the strcmp() and the refcount_inc(). If the
last reference drops on another CPU in that window, the reader's
refcount_inc() runs on a counter that has reached zero. refcount_t
catches the addition-on-zero, prints "refcount_t: addition on 0;
use-after-free", saturates the counter, and returns the saturated
pointer to the caller. Session memory is held live by the in-flight
RCU read section, but the kfree_rcu() callback queued from
l2tp_session_free() will free it once the grace period closes; a
caller that dereferences the returned session past that point hits
a slab-use-after-free. On PREEMPT_RT local_bh_disable() is a per-CPU
sleeping lock and the preemption window is real; on stock PREEMPT
kernels local_bh_disable() is a preempt_count increment that closes
the cross-CPU race in practice (see below).
Use refcount_inc_not_zero() and continue the list walk on failure,
matching the other session getters in the file. The ifname getter
is the only session getter in net/l2tp/ that still uses the bare
refcount_inc() pattern; this change restores file-internal
consistency. The success path is unchanged.
Fixes: abe7a1a7d0 ("l2tp: improve tunnel/session refcount helpers")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260523023423.2568972-1-michael.bommarito@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Convert PPPoL2TP socket's getsockopt implementation to use the new
getsockopt_iter callback with sockopt_t.
Key changes:
- Replace (char __user *optval, int __user *optlen) with sockopt_t *opt
- Use opt->optlen for buffer length (input) and returned size (output)
- Use copy_to_iter() instead of put_user()/copy_to_user()
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260520-getsock_four-v3-4-b8c0b16b7780@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
An unprivileged local user can pin a host CPU indefinitely in
l2tp_session_get_by_ifname() by issuing L2TP_CMD_SESSION_GET on
L2TP_ATTR_IFNAME concurrently with L2TP_CMD_SESSION_CREATE and
L2TP_CMD_SESSION_DELETE on the same tunnel. All three commands take
GENL_UNS_ADMIN_PERM, so CAP_NET_ADMIN in the netns user namespace
suffices; on any host that has l2tp_core loaded the trigger is
reachable from a standard `unshare -Urn` sandbox.
l2tp_session_unhash() removes a session from tunnel->session_list
with list_del_init(), but that list is walked by
l2tp_session_get_by_ifname() with list_for_each_entry_rcu() under
rcu_read_lock_bh(). list_del_init() leaves the deleted entry's
next/prev self-pointing; a reader that has loaded the entry and
then advances pos->list.next reads &session->list, container_of()s
back to the same session, and list_for_each_entry_rcu() never
reaches the list head. The CPU stays in strcmp() inside the
walker, with BH and preemption disabled, so RCU grace periods on
the host stall behind it and the wedged thread cannot be killed
(SIGKILL is delivered on syscall return).
Use list_del_rcu() to match the existing list_add_rcu() in
l2tp_session_register(); the deleted session remains visible to
in-flight walkers with consistent next/prev pointers until
kfree_rcu() in l2tp_session_free() releases it. tunnel->session_list
has exactly one list_del_init() call site; the list_del_init
(&session->clist) at l2tp_core.c:533 operates on the per-collision
list, which is not walked under RCU. list_empty(&session->list) is
not used anywhere in net/l2tp/ after the unhash point, so dropping
the post-delete self-init is safe; the fix has no userspace-visible
behavior change.
Fixes: 89b768ec2d ("l2tp: use rcu list add/del when updating lists")
Cc: stable@vger.kernel.org # 6.11+
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260518183447.64078-1-michael.bommarito@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.
Even setup_udp_tunnel_sock() does not need struct socket.
Let's change setup_udp_tunnel_sock() to take struct sock
instead of struct socket.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Maintaining a modular IPv6 stack offers image size savings for specific
setups, this benefit is outweighed by the architectural burden it
imposes on the subsystems on implementation and maintenance. Therefore,
drop it.
Change CONFIG_IPV6 from tristate to bool. Remove all Kconfig
dependencies across the tree that explicitly checked for IPV6=m. In
addition, remove MODULE_DESCRIPTION(), MODULE_ALIAS(), MODULE_AUTHOR()
and MODULE_LICENSE().
This is also replacing module_init() by device_initcall(). It is not
possible to use fs_initcall() as IPv4 does because that creates a race
condition on IPv6 addrconf.
Finally, modify the default configs from CONFIG_IPV6=m to CONFIG_IPV6=y
except for m68k as according to the bloat-o-meter the image is
increasing by 330KB~ and that isn't acceptable. Instead, disable IPv6 on
this architecture by default. This is aligned with m68k RAM requirements
and recommendations [1].
[1] http://www.linux-m68k.org/faq/ram.html
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Tested-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org> # arm64
Link: https://patch.msgid.link/20260325120928.15848-2-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
chan.hdrlen is read once at channel registration by
ppp_register_net_channel(), and used to set the PPP net device's
hard_header_len. It was set to PPPOL2TP_L2TP_HDR_SIZE_NOSEQ (6), which
is 4 bytes too small if sequence numbers are later enabled via
setsockopt(PPPOL2TP_SO_SENDSEQ), causing unnecessary skb reallocations
on the TX path.
The setsockopt handler attempted to change netdev's hard_header_len by
updating chan.hdrlen, but the PPP layer never re-reads it after the
registration, so the update had no effect.
To avoid the unnecessary reallocations, set chan.hdrlen to
PPPOL2TP_L2TP_HDR_SIZE_SEQ (10) unconditionally at registration and
remove the ineffective update in the setsockopt callback.
Signed-off-by: Qingfang Deng <dqfext@gmail.com>
Link: https://patch.msgid.link/20260317054141.524879-1-dqfext@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cross-merge networking fixes after downstream PR (net-7.0-rc2).
Conflicts:
tools/testing/selftests/drivers/net/hw/rss_ctx.py
19c3a2a81d ("selftests: drv-net: rss: Generate unique ports for RSS context tests")
ce5a0f4612 ("selftests: drv-net: rss_ctx: test RSS contexts persist after ifdown/up")
include/net/inet_connection_sock.h
858d2a4f67 ("tcp: fix potential race in tcp_v6_syn_recv_sock()")
fcd3d039fa ("tcp: make tcp_v{4,6}_send_check() static")
https://lore.kernel.org/aZ8PSFLzBrEU3I89@sirena.org.uk
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/pool.c
69050f8d6d ("treewide: Replace kmalloc with kmalloc_obj for non-scalar types")
bf4afc53b7 ("Convert 'alloc_obj' family to use the new default GFP_KERNEL argument")
8a96b9144f ("net/mlx5e: Alloc xsk channel param out of mlx5e_open_xsk()")
Adjacent changes:
net/netfilter/ipvs/ip_vs_ctl.c
c59bd9e62e ("ipvs: use more counters to avoid service lookups")
bf4afc53b7 ("Convert 'alloc_obj' family to use the new default GFP_KERNEL argument")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Cross-merge networking fixes after downstream PR (net-6.18-rc7).
No conflicts, adjacent changes:
tools/testing/selftests/net/af_unix/Makefile
e1bb28bf13 ("selftest: af_unix: Add test for SO_PEEK_OFF.")
45a1cd8346 ("selftests: af_unix: Add tests for ECONNRESET and EOF semantics")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The L2TP stack did not reset the skb control buffer before sending the
encapsulated package.
In a setup with an ath10k radio and batman-adv over an L2TP tunnel
massive fragmentations happen sporadically if the L2TP tunnel is
established over IPv4.
L2TP might reset some of the fields in the IP control buffer, but L2TP
assumes the type of the control buffer to be of an IPv4 packet.
In case the L2TP interface is used as a batadv hardif or the packet is
an IPv6 packet, this assumption breaks.
Clear the entire control buffer to avoid such mishaps altogether.
Fixes: f77ae93904 ("[PPPOL2TP]: Reset meta-data in xmit function")
Signed-off-by: David Bauer <mail@david-bauer.net>
Link: https://patch.msgid.link/20251118001619.242107-1-mail@david-bauer.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Convert struct proto pre_connect(), connect(), bind(), and bind_add()
callback function prototypes from struct sockaddr to struct sockaddr_unsized.
This does not change per-implementation use of sockaddr for passing around
an arbitrarily sized sockaddr struct. Those will be addressed in future
patches.
Additionally removes the no longer referenced struct sockaddr from
include/net/inet_common.h.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-5-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops bind() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
pppol2tp_session_get_sock() is using RCU, it must be ready
for sk_refcnt being zero.
Commit ee40fb2e1e ("l2tp: protect sock pointer of
struct pppol2tp_session with RCU") was correct because it
had a call_rcu(..., pppol2tp_put_sk) which was later removed in blamed commit.
pppol2tp_recv() can use pppol2tp_session_get_sock() as well.
Fixes: c5cbaef992 ("l2tp: refactor ppp socket/session relationship")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Chapman <jchapman@katalix.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Link: https://patch.msgid.link/20250826134435.1683435-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Move the more esoteric helpers for netdev instance lock to
a dedicated header. This avoids growing netdevice.h to infinity
and makes rebuilding the kernel much faster (after touching
the header with the helpers).
The main netdev_lock() / netdev_unlock() functions are used
in static inlines in netdevice.h and will probably be used
most commonly, so keep them in netdevice.h.
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250307183006.2312761-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For PPPoE, PPTP, and PPPoL2TP, the start_xmit() function directly
forwards packets to the underlying network stack and never returns
anything other than 1. So these interfaces do not require a qdisc,
and the IFF_NO_QUEUE flag should be set.
Introduces a direct_xmit flag in struct ppp_channel to indicate when
IFF_NO_QUEUE should be applied. The flag is set in ppp_connect_channel()
for relevant protocols.
While at it, remove the usused latency member from struct ppp_channel.
Signed-off-by: Qingfang Deng <dqfext@gmail.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250301135517.695809-1-dqfext@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This initializes tclass and dontfrag before cmsg parsing, removing the
need for explicit checks against -1 in each caller.
Leave hlimit set to -1, because its full initialization
(in ip6_sk_dst_hoplimit) requires more state (dst, flowi6, ..).
This also prepares for calling sockcm_init in a follow-on patch.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250214222720.3205500-7-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
l2tp_eth uses the TSTATS infrastructure (dev_sw_netstats_*()) for RX
and TX packet counters and DEV_STATS_INC for dropped counters.
Consolidate that using the DSTATS infrastructure, which can
handle both packet counters and packet drops. Statistics that don't
fit DSTATS are still updated atomically with DEV_STATS_INC().
This change is inspired by the introduction of DSTATS helpers and
their use in other udp tunnel drivers:
Link: https://lore.kernel.org/all/cover.1733313925.git.gnault@redhat.com/
Signed-off-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In l2tp's net exit handler, we check that an IDR is empty before
destroying it:
WARN_ON_ONCE(!idr_is_empty(&pn->l2tp_tunnel_idr));
idr_destroy(&pn->l2tp_tunnel_idr);
By forcing memory allocation failures in idr_alloc_32, syzbot is able
to provoke a condition where idr_is_empty returns false despite there
being no items in the IDR. This turns out to be because the radix tree
of the IDR contains only internal radix-tree nodes and it is this that
causes idr_is_empty to return false. The internal nodes are cleaned by
idr_destroy.
Use idr_for_each to check that the IDR is empty instead of
idr_is_empty to avoid the problem.
Reported-by: syzbot+332fe1e67018625f63c9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=332fe1e67018625f63c9
Fixes: 73d33bd063 ("l2tp: avoid using drain_workqueue in l2tp_pre_exit_net")
Signed-off-by: James Chapman <jchapman@katalix.com>
Link: https://patch.msgid.link/20241118140411.1582555-1-jchapman@katalix.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
NETIF_F_LLTX can't be changed via Ethtool and is not a feature,
rather an attribute, very similar to IFF_NO_QUEUE (and hot).
Free one netdev_features_t bit and make it a "hot" private flag.
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Recent commit fc7ec7f554 ("l2tp: delete sessions using work queue")
incorrectly uses drain_workqueue. The use of drain_workqueue in
l2tp_pre_exit_net is flawed because the workqueue is shared by all
nets and it is therefore possible for new work items to be queued
for other nets while drain_workqueue runs.
Instead of using drain_workqueue, use __flush_workqueue twice. The
first one will run all tunnel delete work items and any work already
queued. When tunnel delete work items are run, they may queue
new session delete work items, which the second __flush_workqueue will
run.
In l2tp_exit_net, warn if any of the net's idr lists are not empty.
Fixes: fc7ec7f554 ("l2tp: delete sessions using work queue")
Signed-off-by: James Chapman <jchapman@katalix.com>
Link: https://patch.msgid.link/20240823142257.692667-1-jchapman@katalix.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Recent commit ed8ebee6de ("l2tp: have l2tp_ip_destroy_sock use
ip_flush_pending_frames") was incorrect in that l2tp_ip does not use
socket cork and ip_flush_pending_frames is for sockets that do. Use
__skb_queue_purge instead and remove the unnecessary lock.
Also unexport ip_flush_pending_frames since it was originally exported
in commit 4ff8863419 ("ipv4: export ip_flush_pending_frames") for
l2tp and is not used by other modules.
Suggested-by: xiyou.wangcong@gmail.com
Signed-off-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20240819143333.3204957-1-jchapman@katalix.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot exposes a race where a net used by l2tp is removed while an
existing pppol2tp socket is closed. In l2tp_pre_exit_net, l2tp queues
TUNNEL_DELETE work items to close each tunnel in the net. When these
are run, new SESSION_DELETE work items are queued to delete each
session in the tunnel. This all happens in drain_workqueue. However,
drain_workqueue allows only new work items if they are queued by other
work items which are already in the queue. If pppol2tp_release runs
after drain_workqueue has started, it may queue a SESSION_DELETE work
item, which results in the warning below in drain_workqueue.
Address this by flushing the workqueue before drain_workqueue such
that all queued TUNNEL_DELETE work items run before drain_workqueue is
started. This will queue SESSION_DELETE work items for each session in
the tunnel, hence pppol2tp_release or other API requests won't queue
SESSION_DELETE requests once drain_workqueue is started.
WARNING: CPU: 1 PID: 5467 at kernel/workqueue.c:2259 __queue_work+0xcd3/0xf50 kernel/workqueue.c:2258
Modules linked in:
CPU: 1 UID: 0 PID: 5467 Comm: syz.3.43 Not tainted 6.11.0-rc1-syzkaller-00247-g3608d6aca5e7 #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__queue_work+0xcd3/0xf50 kernel/workqueue.c:2258
Code: ff e8 11 84 36 00 90 0f 0b 90 e9 1e fd ff ff e8 03 84 36 00 eb 13 e8 fc 83 36 00 eb 0c e8 f5 83 36 00 eb 05 e8 ee 83 36 00 90 <0f> 0b 90 48 83 c4 60 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc
RSP: 0018:ffffc90004607b48 EFLAGS: 00010093
RAX: ffffffff815ce274 RBX: ffff8880661fda00 RCX: ffff8880661fda00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff815cd6d4 R09: 0000000000000000
R10: ffffc90004607c20 R11: fffff520008c0f85 R12: ffff88802ac33800
R13: ffff88802ac339c0 R14: dffffc0000000000 R15: 0000000000000008
FS: 00005555713eb500(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000001eda6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
queue_work_on+0x1c2/0x380 kernel/workqueue.c:2392
pppol2tp_release+0x163/0x230 net/l2tp/l2tp_ppp.c:445
__sock_release net/socket.c:659 [inline]
sock_close+0xbc/0x240 net/socket.c:1421
__fput+0x24a/0x8a0 fs/file_table.c:422
task_work_run+0x24f/0x310 kernel/task_work.c:228
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f061e9779f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffff1c1fce8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000001017d RCX: 00007f061e9779f9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007ffff1c1fdc0 R08: 0000000000000001 R09: 00007ffff1c1ffcf
R10: 00007f061e800000 R11: 0000000000000246 R12: 0000000000000032
R13: 00007ffff1c1fde0 R14: 00007ffff1c1fe00 R15: ffffffffffffffff
</TASK>
Fixes: fc7ec7f554 ("l2tp: delete sessions using work queue")
Reported-by: syzbot+0e85b10481d2f5478053@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0e85b10481d2f5478053
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp_eth uses old-style dev->stats for fastpath packet/byte
counters. Convert it to use dev->tstats per-cpu counters.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp_tunnel_inc_refcount and l2tp_session_inc_refcount wrap
refcount_inc. They add no value so just use the refcount APIs directly
and drop l2tp's helpers. l2tp already uses refcount_inc_not_zero
anyway.
Rename l2tp_tunnel_dec_refcount and l2tp_session_dec_refcount to
l2tp_tunnel_put and l2tp_session_put to better match their use pairing
various _get getters.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp netlink and procfs/debugfs iterate over tunnel and session lists
to obtain data. They currently use very inefficient get_nth functions
to do so. Replace these with get_next.
For netlink, use nl cb->ctx[] for passing state instead of the
obsolete cb->args[].
l2tp_tunnel_get_nth and l2tp_session_get_nth are no longer used so
they can be removed.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp management APIs and procfs/debugfs iterate over l2tp tunnel and
session lists. Since these lists are now implemented using IDR, we can
use IDR get_next APIs to iterate them. Add tunnel/session get_next
functions to do so.
The session get_next functions get the next session in a given tunnel
and need to account for l2tpv2 and l2tpv3 differences:
* l2tpv2 sessions are keyed by tunnel ID / session ID. Iteration for
a given tunnel ID, TID, can therefore start with a key given by
TID/0 and finish when the next entry's tunnel ID is not TID. This
is possible only because the tunnel ID part of the key is the upper
16 bits and the session ID part the lower 16 bits; when idr_next
increments the key value, it therefore finds the next sessions of
the current tunnel before those of the next tunnel. Entries with
session ID 0 are always skipped because they are used internally by
pppol2tp.
* l2tpv3 sessions are keyed by session ID. Iteration starts at the
first IDR entry and skips entries where the tunnel does not
match. Iteration must also consider session ID collisions and walk
the list of colliding sessions (if any) for one which matches the
supplied tunnel.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To handle colliding l2tpv3 session IDs, l2tp_v3_session_get searches a
hashed list keyed by ID and sk. Although unlikely, if hash keys
collide, it is possible that hash_for_each_possible loops over a
session which doesn't have the ID that we are searching for. So check
for session ID match when looping over possible hash key matches.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp_ip[6] have always used global socket tables. It is therefore not
possible to create l2tpip sockets in different namespaces with the
same socket address.
To support this, move l2tpip socket tables to pernet data.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update l2tp to remove the inline keyword from several functions in C
sources, since this is now discouraged.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit fd558d186d ("l2tp: Split pppol2tp patch into separate l2tp and
ppp parts") converted net->gen->ptr[pppol2tp_net_id] in l2tp_ppp.c to
net->gen->ptr[l2tp_net_id] in l2tp_core.c.
Now the leftover wastes one entry of net->gen->ptr[] in each netns.
Let's avoid the unwanted allocation.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
