Commit b39b5f411d ("bpf: add cg_skb_is_valid_access for
BPF_PROG_TYPE_CGROUP_SKB") added support for returning pkt pointers
for direct packet access. Given this program type is allowed for both
unprivileged and privileged users, we shouldn't allow unprivileged
ones to use it, e.g. besides others one reason would be to avoid any
potential speculation on the packet test itself, thus guard this for
root only.
Fixes: b39b5f411d ("bpf: add cg_skb_is_valid_access for BPF_PROG_TYPE_CGROUP_SKB")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The cleanup path will put the target net when netnsid is set. So we must
reset netnsid if the input is invalid.
Fixes: d7e38611b8 ("net/ipv4: Put target net when address dump fails due to bad attributes")
Fixes: 242afaa696 ("net/ipv6: Put target net when address dump fails due to bad attributes")
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull compat_ioctl fixes from Al Viro:
"A bunch of compat_ioctl fixes, mostly in bluetooth.
Hopefully, most of fs/compat_ioctl.c will get killed off over the next
few cycles; between this, tty series already merged and Arnd's work
this cycle ought to take a good chunk out of the damn thing..."
* 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
hidp: fix compat_ioctl
hidp: constify hidp_connection_add()
cmtp: fix compat_ioctl
bnep: fix compat_ioctl
compat_ioctl: trim the pointless includes
Pull timekeeping updates from Thomas Gleixner:
"The timers and timekeeping departement provides:
- Another large y2038 update with further preparations for providing
the y2038 safe timespecs closer to the syscalls.
- An overhaul of the SHCMT clocksource driver
- SPDX license identifier updates
- Small cleanups and fixes all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
tick/sched : Remove redundant cpu_online() check
clocksource/drivers/dw_apb: Add reset control
clocksource: Remove obsolete CLOCKSOURCE_OF_DECLARE
clocksource/drivers: Unify the names to timer-* format
clocksource/drivers/sh_cmt: Add R-Car gen3 support
dt-bindings: timer: renesas: cmt: document R-Car gen3 support
clocksource/drivers/sh_cmt: Properly line-wrap sh_cmt_of_table[] initializer
clocksource/drivers/sh_cmt: Fix clocksource width for 32-bit machines
clocksource/drivers/sh_cmt: Fixup for 64-bit machines
clocksource/drivers/sh_tmu: Convert to SPDX identifiers
clocksource/drivers/sh_mtu2: Convert to SPDX identifiers
clocksource/drivers/sh_cmt: Convert to SPDX identifiers
clocksource/drivers/renesas-ostm: Convert to SPDX identifiers
clocksource: Convert to using %pOFn instead of device_node.name
tick/broadcast: Remove redundant check
RISC-V: Request newstat syscalls
y2038: signal: Change rt_sigtimedwait to use __kernel_timespec
y2038: socket: Change recvmmsg to use __kernel_timespec
y2038: sched: Change sched_rr_get_interval to use __kernel_timespec
y2038: utimes: Rework #ifdef guards for compat syscalls
...
The intent of ip6_route_check_nh_onlink is to make sure the gateway
given for an onlink route is not actually on a connected route for
a different interface (e.g., 2001:db8:1::/64 is on dev eth1 and then
an onlink route has a via 2001:db8:1::1 dev eth2). If the gateway
lookup hits the default route then it most likely will be a different
interface than the onlink route which is ok.
Update ip6_route_check_nh_onlink to disregard the device mismatch
if the gateway lookup hits the default route. Turns out the existing
onlink tests are passing because there is no default route or it is
an unreachable default, so update the onlink tests to have a default
route other than unreachable.
Fixes: fc1e64e109 ("net/ipv6: Add support for onlink flag")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Marco reported an error with hfsc:
root@Calimero:~# tc qdisc add dev eth0 root handle 1:0 hfsc default 1
Error: Attribute failed policy validation.
Apparently a few implementations pass TCA_OPTIONS as a binary instead
of nested attribute, so drop TCA_OPTIONS from the policy.
Fixes: 8b4c3cdd9d ("net: sched: Add policy validation for tc attributes")
Reported-by: Marco Berizzi <pupilla@libero.it>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current handling of CHECKSUM_COMPLETE packets by the UDP stack is
incorrect for any packet that has an incorrect checksum value.
udp4/6_csum_init() will both make a call to
__skb_checksum_validate_complete() to initialize/validate the csum
field when receiving a CHECKSUM_COMPLETE packet. When this packet
fails validation, skb->csum will be overwritten with the pseudoheader
checksum so the packet can be fully validated by software, but the
skb->ip_summed value will be left as CHECKSUM_COMPLETE so that way
the stack can later warn the user about their hardware spewing bad
checksums. Unfortunately, leaving the SKB in this state can cause
problems later on in the checksum calculation.
Since the the packet is still marked as CHECKSUM_COMPLETE,
udp_csum_pull_header() will SUBTRACT the checksum of the UDP header
from skb->csum instead of adding it, leaving us with a garbage value
in that field. Once we try to copy the packet to userspace in the
udp4/6_recvmsg(), we'll make a call to skb_copy_and_csum_datagram_msg()
to checksum the packet data and add it in the garbage skb->csum value
to perform our final validation check.
Since the value we're validating is not the proper checksum, it's possible
that the folded value could come out to 0, causing us not to drop the
packet. Instead, we believe that the packet was checksummed incorrectly
by hardware since skb->ip_summed is still CHECKSUM_COMPLETE, and we attempt
to warn the user with netdev_rx_csum_fault(skb->dev);
Unfortunately, since this is the UDP path, skb->dev has been overwritten
by skb->dev_scratch and is no longer a valid pointer, so we end up
reading invalid memory.
This patch addresses this problem in two ways:
1) Do not use the dev pointer when calling netdev_rx_csum_fault()
from skb_copy_and_csum_datagram_msg(). Since this gets called
from the UDP path where skb->dev has been overwritten, we have
no way of knowing if the pointer is still valid. Also for the
sake of consistency with the other uses of
netdev_rx_csum_fault(), don't attempt to call it if the
packet was checksummed by software.
2) Add better CHECKSUM_COMPLETE handling to udp4/6_csum_init().
If we receive a packet that's CHECKSUM_COMPLETE that fails
verification (i.e. skb->csum_valid == 0), check who performed
the calculation. It's possible that the checksum was done in
software by the network stack earlier (such as Netfilter's
CONNTRACK module), and if that says the checksum is bad,
we can drop the packet immediately instead of waiting until
we try and copy it to userspace. Otherwise, we need to
mark the SKB as CHECKSUM_NONE, since the skb->csum field
no longer contains the full packet checksum after the
call to __skb_checksum_validate_complete().
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Fixes: c84d949057 ("udp: copy skb->truesize in the first cache line")
Cc: Sam Kumar <samanthakumar@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Sean Tranchetti <stranche@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an address, route or netconf dump request is sent for AF_UNSPEC, then
rtnl_dump_all is used to do the dump across all address families. If one
of the dumpit functions fails (e.g., invalid attributes in the dump
request) then rtnl_dump_all needs to propagate that error so the user
gets an appropriate response instead of just getting no data.
Fixes: effe679266 ("net: Enable kernel side filtering of route dumps")
Fixes: 5fcd266a9f ("net/ipv4: Add support for dumping addresses for a specific device")
Fixes: 6371a71f3a ("net/ipv6: Add support for dumping addresses for a specific device")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When doing a route dump across all address families, do not error out
if the table does not exist. This allows a route dump for AF_UNSPEC
with a table id that may only exist for some of the families.
Do return the table does not exist error if dumping routes for a
specific family and the table does not exist.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If tgt_net is set based on IFA_TARGET_NETNSID attribute in the dump
request, make sure all error paths call put_net.
Fixes: 6371a71f3a ("net/ipv6: Add support for dumping addresses for a specific device")
Fixes: ed6eff1179 ("net/ipv6: Update inet6_dump_addr for strict data checking")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If tgt_net is set based on IFA_TARGET_NETNSID attribute in the dump
request, make sure all error paths call put_net.
Fixes: 5fcd266a9f ("net/ipv4: Add support for dumping addresses for a specific device")
Fixes: c33078e3df ("net/ipv4: Update inet_dump_ifaddr for strict data checking")
Reported-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull documentation updates from Jonathan Corbet:
"This is a fairly typical cycle for documentation. There's some welcome
readability improvements for the formatted output, some LICENSES
updates including the addition of the ISC license, the removal of the
unloved and unmaintained 00-INDEX files, the deprecated APIs document
from Kees, more MM docs from Mike Rapoport, and the usual pile of typo
fixes and corrections"
* tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits)
docs: Fix typos in histogram.rst
docs: Introduce deprecated APIs list
kernel-doc: fix declaration type determination
doc: fix a typo in adding-syscalls.rst
docs/admin-guide: memory-hotplug: remove table of contents
doc: printk-formats: Remove bogus kobject references for device nodes
Documentation: preempt-locking: Use better example
dm flakey: Document "error_writes" feature
docs/completion.txt: Fix a couple of punctuation nits
LICENSES: Add ISC license text
LICENSES: Add note to CDDL-1.0 license that it should not be used
docs/core-api: memory-hotplug: add some details about locking internals
docs/core-api: rename memory-hotplug-notifier to memory-hotplug
docs: improve readability for people with poorer eyesight
yama: clarify ptrace_scope=2 in Yama documentation
docs/vm: split memory hotplug notifier description to Documentation/core-api
docs: move memory hotplug description into admin-guide/mm
doc: Fix acronym "FEKEK" in ecryptfs
docs: fix some broken documentation references
iommu: Fix passthrough option documentation
...
Pull tty ioctl updates from Al Viro:
"This is the compat_ioctl work related to tty ioctls.
Quite a bit of dead code taken out, all tty-related stuff gone from
fs/compat_ioctl.c. A bunch of compat bugs fixed - some still remain,
but all more or less generic tty-related ioctls should be covered
(remaining issues are in things like driver-private ioctls in a pcmcia
serial card driver not getting properly handled in 32bit processes on
64bit host, etc)"
* 'work.tty-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (53 commits)
kill TIOCSERGSTRUCT
change semantics of ldisc ->compat_ioctl()
kill TIOCSER[SG]WILD
synclink_gt(): fix compat_ioctl()
pty: fix compat ioctls
compat_ioctl - kill keyboard ioctl handling
gigaset: add ->compat_ioctl()
vt_compat_ioctl(): clean up, use compat_ptr() properly
gigaset: don't try to printk userland buffer contents
dgnc: don't bother with (empty) stub for TCXONC
dgnc: leave TIOC[GS]SOFTCAR to ldisc
remove fallback to drivers for TIOCGICOUNT
dgnc: break-related ioctls won't reach ->ioctl()
kill the rest of tty COMPAT_IOCTL() entries
dgnc: TIOCM... won't reach ->ioctl()
isdn_tty: TCSBRK{,P} won't reach ->ioctl()
kill capinc_tty_ioctl()
take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()
synclink: reduce pointless checks in ->ioctl()
complete ->[sg]et_serial() switchover
...
With EDT model, SRTT no longer is inflated by pacing delays.
This means that RTO and some other xmit timers might be setup
incorrectly. This is particularly visible with either :
- Very small enforced pacing rates (SO_MAX_PACING_RATE)
- Reduced rto (from the default 200 ms)
This can lead to TCP flows aborts in the worst case,
or spurious retransmits in other cases.
For example, this session gets far more throughput
than the requested 80kbit :
$ netperf -H 127.0.0.2 -l 100 -- -q 10000
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 127.0.0.2 () port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
540000 262144 262144 104.00 2.66
With the fix :
$ netperf -H 127.0.0.2 -l 100 -- -q 10000
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 127.0.0.2 () port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
540000 262144 262144 104.00 0.12
EDT allows for better control of rtx timers, since TCP has
a better idea of the earliest departure time of each skb
in the rtx queue. We only have to eventually add to the
timer the difference of the EDT time with current time.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.
Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.
Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.
Signed-off-by: David Howells <dhowells@redhat.com>
Use accessor functions to access an iterator's type and direction. This
allows for the possibility of using some other method of determining the
type of iterator than if-chains with bitwise-AND conditions.
Signed-off-by: David Howells <dhowells@redhat.com>
This reverts commit dd979b4df8.
This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an
internal TCP socket for the initial handshake with the remote peer.
Whenever the SMC connection can not be established this TCP socket is
used as a fallback. All socket operations on the SMC socket are then
forwarded to the TCP socket. In case of poll, the file->private_data
pointer references the SMC socket because the TCP socket has no file
assigned. This causes tcp_poll to wait on the wrong socket.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We no longer need to worry about whether or not the entry is hashed in
order to figure out if the contents are valid. We only care whether or
not the refcount is non-zero.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree:
1) rbtree lookup from control plane returns the left-hand side element
of the range when the interval end flag is set on.
2) osf extension is not supported from the input path, reject this from
the control plane, from Fernando Fernandez Mancera.
3) xt_TEE is leaving output interface unset due to a recent incorrect
netns rework, from Taehee Yoo.
4) xt_TEE allows to select an interface which does not belong to this
netnamespace, from Taehee Yoo.
5) Zero private extension area in nft_compat, just like we do in x_tables,
otherwise we leak kernel memory to userspace.
6) Missing .checkentry and .destroy entries in new DNAT extensions breaks
it since we never load nf_conntrack dependencies, from Paolo Abeni.
7) Do not remove flowtable hook from netns exit path, the netdevice handler
already deals with this, also from Taehee Yoo.
8) Only cleanup flowtable entries that reside in this netnamespace, also
from Taehee Yoo.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
syzkaller triggered a use-after-free [1], caused by a combination of
skb_get() in llc_conn_state_process() and usage of sk_eat_skb()
sk_eat_skb() is assuming the skb about to be freed is only used by
the current thread. TCP/DCCP stacks enforce this because current
thread holds the socket lock.
llc_conn_state_process() wants to make sure skb does not disappear,
and holds a reference on the skb it manipulates. But as soon as this
skb is added to socket receive queue, another thread can consume it.
This means that llc must use regular skb_unlink() and kfree_skb()
so that both producer and consumer can safely work on the same skb.
[1]
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:967 [inline]
BUG: KASAN: use-after-free in kfree_skb+0xb7/0x580 net/core/skbuff.c:655
Read of size 4 at addr ffff8801d1f6fba4 by task ksoftirqd/1/18
CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.19.0-rc8+ #295
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+0x1c4/0x2b6 lib/dump_stack.c:113
print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
refcount_read include/linux/refcount.h:43 [inline]
skb_unref include/linux/skbuff.h:967 [inline]
kfree_skb+0xb7/0x580 net/core/skbuff.c:655
llc_sap_state_process+0x9b/0x550 net/llc/llc_sap.c:224
llc_sap_rcv+0x156/0x1f0 net/llc/llc_sap.c:297
llc_sap_handler+0x65e/0xf80 net/llc/llc_sap.c:438
llc_rcv+0x79e/0xe20 net/llc/llc_input.c:208
__netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
__netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
process_backlog+0x218/0x6f0 net/core/dev.c:5829
napi_poll net/core/dev.c:6249 [inline]
net_rx_action+0x7c5/0x1950 net/core/dev.c:6315
__do_softirq+0x30c/0xb03 kernel/softirq.c:292
run_ksoftirqd+0x94/0x100 kernel/softirq.c:653
smpboot_thread_fn+0x68b/0xa00 kernel/smpboot.c:164
kthread+0x35a/0x420 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
Allocated by task 18:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
kmem_cache_alloc_node+0x144/0x730 mm/slab.c:3644
__alloc_skb+0x119/0x770 net/core/skbuff.c:193
alloc_skb include/linux/skbuff.h:995 [inline]
llc_alloc_frame+0xbc/0x370 net/llc/llc_sap.c:54
llc_station_ac_send_xid_r net/llc/llc_station.c:52 [inline]
llc_station_rcv+0x1dc/0x1420 net/llc/llc_station.c:111
llc_rcv+0xc32/0xe20 net/llc/llc_input.c:220
__netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
__netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
process_backlog+0x218/0x6f0 net/core/dev.c:5829
napi_poll net/core/dev.c:6249 [inline]
net_rx_action+0x7c5/0x1950 net/core/dev.c:6315
__do_softirq+0x30c/0xb03 kernel/softirq.c:292
Freed by task 16383:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
__cache_free mm/slab.c:3498 [inline]
kmem_cache_free+0x83/0x290 mm/slab.c:3756
kfree_skbmem+0x154/0x230 net/core/skbuff.c:582
__kfree_skb+0x1d/0x20 net/core/skbuff.c:642
sk_eat_skb include/net/sock.h:2366 [inline]
llc_ui_recvmsg+0xec2/0x1610 net/llc/af_llc.c:882
sock_recvmsg_nosec net/socket.c:794 [inline]
sock_recvmsg+0xd0/0x110 net/socket.c:801
___sys_recvmsg+0x2b6/0x680 net/socket.c:2278
__sys_recvmmsg+0x303/0xb90 net/socket.c:2390
do_sys_recvmmsg+0x181/0x1a0 net/socket.c:2466
__do_sys_recvmmsg net/socket.c:2484 [inline]
__se_sys_recvmmsg net/socket.c:2480 [inline]
__x64_sys_recvmmsg+0xbe/0x150 net/socket.c:2480
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
The buggy address belongs to the object at ffff8801d1f6fac0
which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 228 bytes inside of
232-byte region [ffff8801d1f6fac0, ffff8801d1f6fba8)
The buggy address belongs to the page:
page:ffffea000747dbc0 count:1 mapcount:0 mapping:ffff8801d9be7680 index:0xffff8801d1f6fe80
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0007346e88 ffffea000705b108 ffff8801d9be7680
raw: ffff8801d1f6fe80 ffff8801d1f6f0c0 000000010000000b 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8801d1f6fa80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff8801d1f6fb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801d1f6fb80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
^
ffff8801d1f6fc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8801d1f6fc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
