SELinux tries to support setting/clearing of /proc/pid/attr attributes
from the shell by ignoring terminating newlines and treating an
attribute value that begins with a NUL or newline as an attempt to
clear the attribute. However, the test for clearing attributes has
always been wrong; it has an off-by-one error, and this could further
lead to reading past the end of the allocated buffer since commit
bb646cdb12 ("proc_pid_attr_write():
switch to memdup_user()"). Fix the off-by-one error.
Even with this fix, setting and clearing /proc/pid/attr attributes
from the shell is not straightforward since the interface does not
support multiple write() calls (so shells that write the value and
newline separately will set and then immediately clear the attribute,
requiring use of echo -n to set the attribute), whereas trying to use
echo -n "" to clear the attribute causes the shell to skip the
write() call altogether since POSIX says that a zero-length write
causes no side effects. Thus, one must use echo -n to set and echo
without -n to clear, as in the following example:
$ echo -n unconfined_u:object_r:user_home_t:s0 > /proc/$$/attr/fscreate
$ cat /proc/$$/attr/fscreate
unconfined_u:object_r:user_home_t:s0
$ echo "" > /proc/$$/attr/fscreate
$ cat /proc/$$/attr/fscreate
Note the use of /proc/$$ rather than /proc/self, as otherwise
the cat command will read its own attribute value, not that of the shell.
There are no users of this facility to my knowledge; possibly we
should just get rid of it.
UPDATE: Upon further investigation it appears that a local process
with the process:setfscreate permission can cause a kernel panic as a
result of this bug. This patch fixes CVE-2017-2618.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: added the update about CVE-2017-2618 to the commit description]
Cc: stable@vger.kernel.org # 3.5: d6ea83ec68
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Pull networking fixes from David Miller:
1) Load correct firmware in rtl8192ce wireless driver, from Jurij
Smakov.
2) Fix leak of tx_ring and tx_cq due to overwriting in mlx4 driver,
from Martin KaFai Lau.
3) Need to reference count PHY driver module when it is attached, from
Mao Wenan.
4) Don't do zero length vzalloc() in ethtool register dump, from
Stanislaw Gruszka.
5) Defer net_disable_timestamp() to a workqueue to get out of locking
issues, from Eric Dumazet.
6) We cannot drop the SKB dst when IP options refer to them, fix also
from Eric Dumazet.
7) Incorrect packet header offset calculations in ip6_gre, again from
Eric Dumazet.
8) Missing tcp_v6_restore_cb() causes use-after-free, from Eric too.
9) tcp_splice_read() can get into an infinite loop with URG, and hey
it's from Eric once more.
10) vnet_hdr_sz can change asynchronously, so read it once during
decision making in macvtap and tun, from Willem de Bruijn.
11) Can't use kernel stack for DMA transfers in USB networking drivers,
from Ben Hutchings.
12) Handle csum errors properly in UDP by calling the proper destructor,
from Eric Dumazet.
13) For non-deterministic softirq run when scheduling NAPI from a
workqueue in mlx4, from Benjamin Poirier.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (28 commits)
sctp: check af before verify address in sctp_addr_id2transport
sctp: avoid BUG_ON on sctp_wait_for_sndbuf
mlx4: Invoke softirqs after napi_reschedule
udp: properly cope with csum errors
catc: Use heap buffer for memory size test
catc: Combine failure cleanup code in catc_probe()
rtl8150: Use heap buffers for all register access
pegasus: Use heap buffers for all register access
macvtap: read vnet_hdr_size once
tun: read vnet_hdr_sz once
tcp: avoid infinite loop in tcp_splice_read()
hns: avoid stack overflow with CONFIG_KASAN
ipv6: Fix IPv6 packet loss in scenarios involving roaming + snooping switches
ipv6: tcp: add a missing tcp_v6_restore_cb()
nl80211: Fix mesh HT operation check
mac80211: Fix adding of mesh vendor IEs
mac80211: Allocate a sync skcipher explicitly for FILS AEAD
mac80211: Fix FILS AEAD protection in Association Request frame
ip6_gre: fix ip6gre_err() invalid reads
netlabel: out of bound access in cipso_v4_validate()
...
Commit 6326fec112 ("mm: Use owner_priv bit for PageSwapCache, valid
when PageSwapBacked") aliased PG_swapcache to PG_owner_priv_1 (and
depending on PageSwapBacked being true).
As a result, the KPF_SWAPCACHE bit in '/proc/kpageflags' should now be
synthesized, instead of being shown on unrelated pages which just happen
to have PG_owner_priv_1 set.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 6f29a13061 ("sctp: sctp_addr_id2transport should verify the
addr before looking up assoc") invoked sctp_verify_addr to verify the
addr.
But it didn't check af variable beforehand, once users pass an address
with family = 0 through sockopt, sctp_get_af_specific will return NULL
and NULL pointer dereference will be caused by af->sockaddr_len.
This patch is to fix it by returning NULL if af variable is NULL.
Fixes: 6f29a13061 ("sctp: sctp_addr_id2transport should verify the addr before looking up assoc")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexander Popov reported that an application may trigger a BUG_ON in
sctp_wait_for_sndbuf if the socket tx buffer is full, a thread is
waiting on it to queue more data and meanwhile another thread peels off
the association being used by the first thread.
This patch replaces the BUG_ON call with a proper error handling. It
will return -EPIPE to the original sendmsg call, similarly to what would
have been done if the association wasn't found in the first place.
Acked-by: Alexander Popov <alex.popov@linux.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mlx4 may schedule napi from a workqueue. Afterwards, softirqs are not run
in a deterministic time frame and the following message may be logged:
NOHZ: local_softirq_pending 08
The problem is the same as what was described in commit ec13ee8014
("virtio_net: invoke softirqs after __napi_schedule") and this patch
applies the same fix to mlx4.
Fixes: 07841f9d94 ("net/mlx4_en: Schedule napi when RX buffers allocation fails")
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported that UDP sockets being destroyed would trigger the
WARN_ON(atomic_read(&sk->sk_rmem_alloc)); in inet_sock_destruct()
It turns out we do not properly destroy skb(s) that have wrong UDP
checksum.
Thanks again to syzkaller team.
Fixes : 7c13f97ffd ("udp: do fwd memory scheduling on dequeue")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ben Hutchings says:
====================
net: Fix on-stack USB buffers
Allocating USB buffers on the stack is not portable, and no longer
works on x86_64 (with VMAP_STACK enabled as per default). This
series fixes all the instances I could find where USB networking
drivers do that.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Allocating USB buffers on the stack is not portable, and no longer
works on x86_64 (with VMAP_STACK enabled as per default).
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allocating USB buffers on the stack is not portable, and no longer
works on x86_64 (with VMAP_STACK enabled as per default).
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Willem de Bruijn says:
====================
read vnet_hdr_sz once
Tuntap devices allow concurrent use and update of field vnet_hdr_sz.
Read the field once to avoid TOCTOU.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When IFF_VNET_HDR is enabled, a virtio_net header must precede data.
Data length is verified to be greater than or equal to expected header
length tun->vnet_hdr_sz before copying.
Macvtap functions read the value once, but unless READ_ONCE is used,
the compiler may ignore this and read multiple times. Enforce a single
read and locally cached value to avoid updates between test and use.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When IFF_VNET_HDR is enabled, a virtio_net header must precede data.
Data length is verified to be greater than or equal to expected header
length tun->vnet_hdr_sz before copying.
Read this value once and cache locally, as it can be updated between
the test and use (TOCTOU).
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
CC: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Splicing from TCP socket is vulnerable when a packet with URG flag is
received and stored into receive queue.
__tcp_splice_read() returns 0, and sk_wait_data() immediately
returns since there is the problematic skb in queue.
This is a nice way to burn cpu (aka infinite loop) and trigger
soft lockups.
Again, this gem was found by syzkaller tool.
Fixes: 9c55e01c0c ("[TCP]: Splice receive support.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull libnvdimm fixes from Dan Williams:
"None of these are showstoppers for 4.10 and could wait for 4.11 merge
window, but they are low enough risk for this late in the cycle and
the fixes have waiting users . They have received a build success
notification from the 0day robot, pass the latest ndctl unit tests,
and appeared in next:
- Fix a crash that can result when SIGINT is sent to a process that
is awaiting completion of an address range scrub command. We were
not properly cleaning up the workqueue after
wait_event_interruptible().
- Fix a memory hotplug failure condition that results from not
reserving enough space out of persistent memory for the memmap. By
default we align to 2M allocations that the memory hotplug code
assumes, but if the administrator specifies a non-default
4K-alignment then we can fail to correctly size the reservation.
- A one line fix to improve the predictability of libnvdimm block
device names. A common operation is to reconfigure /dev/pmem0 into
a different mode. For example, a reconfiguration might set a new
mode that reserves some of the capacity for a struct page memmap
array. It surprises users if the device name changes to
"/dev/pmem0.1" after the mode change and then back to /dev/pmem0
after a reboot.
- Add 'const' to some function pointer tables"
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm, pfn: fix memmap reservation size versus 4K alignment
acpi, nfit: fix acpi_nfit_flush_probe() crash
libnvdimm, namespace: do not delete namespace-id 0
nvdimm: constify device_type structures
Pull power management fixes from Rafael Wysocki:
"These add a quirk to intel_pstate to work around a firmware setting
that leads to frequency scaling issues (discovered recently) on some
Intel Kaby Lake processors, fix up the recently added brcmstb-avs
cpufreq driver and avoid false-positive warnings from the runtime PM
framework triggered by recent changes in i915.
Specifics:
- Add an intel_pstate driver quirk to work around a firmware setting
that leads to frequency scaling issues on desktop Intel Kaby Lake
processors in some configurations if the hardware-managed P-states
(HWP) feature is in use (Srinivas Pandruvada)
- Fix up the recently added brcmstb-avs cpufreq driver: fix a bug
related to system suspend and change the sysfs interface to match
the user space expectations (Markus Mayer)
- Modify the runtime PM framework to avoid false-positive warnings
from the might_sleep_if() assertions in it (Rafael Wysocki)"
* tag 'pm-4.10-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / runtime: Avoid false-positive warnings from might_sleep_if()
cpufreq: intel_pstate: Disable energy efficiency optimization
cpufreq: brcmstb-avs-cpufreq: properly retrieve P-state upon suspend
cpufreq: brcmstb-avs-cpufreq: extend sysfs entry brcm_avs_pmap
Pull device mapper fixes from Mike Snitzer:
- a fix for a race in .request_fn request-based DM request handling vs
DM device destruction
- an RCU fix for dm-crypt's kernel keyring support that was included in
4.10-rc1
- a -Wbool-operation warning fix for DM multipath
* tag 'dm-4.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm crypt: replace RCU read-side section with rwsem
dm rq: cope with DM device destruction while in dm_old_request_fn()
dm mpath: cleanup -Wbool-operation warning in choose_pgpath()
Pull media fixes from Mauro Carvalho Chehab:
"A few documentation fixes at CEC (with got promoted from staging for
4.10), and one fix on its core."
* tag 'media/v4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] cec: fix wrong last_la determination
[media] cec-intro.rst: mention the v4l-utils package and CEC utilities
[media] cec rst: remove "This API is not yet finalized" notice
Pull crypto fixes from Herbert Xu:
- use-after-free in algif_aead
- modular aesni regression when pcbc is modular but absent
- bug causing IO page faults in ccp
- double list add in ccp
- NULL pointer dereference in qat (two patches)
- panic in chcr
- NULL pointer dereference in chcr
- out-of-bound access in chcr
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: chcr - Fix key length for RFC4106
crypto: algif_aead - Fix kernel panic on list_del
crypto: aesni - Fix failure when pcbc module is absent
crypto: ccp - Fix double add when creating new DMA command
crypto: ccp - Fix DMA operations when IOMMU is enabled
crypto: chcr - Check device is allocated before use
crypto: chcr - Fix panic on dma_unmap_sg
crypto: qat - zero esram only for DH85x devices
crypto: qat - fix bar discovery for c62x
The use of ACCESS_ONCE() looks like a micro-optimization to force gcc to use
an indexed load for the register address, but it has an absolutely detrimental
effect on builds with gcc-5 and CONFIG_KASAN=y, leading to a very likely
kernel stack overflow aside from very complex object code:
hisilicon/hns/hns_dsaf_gmac.c: In function 'hns_gmac_update_stats':
hisilicon/hns/hns_dsaf_gmac.c:419:1: error: the frame size of 2912 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_ppe.c: In function 'hns_ppe_reset_common':
hisilicon/hns/hns_dsaf_ppe.c:390:1: error: the frame size of 1184 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_ppe.c: In function 'hns_ppe_get_regs':
hisilicon/hns/hns_dsaf_ppe.c:621:1: error: the frame size of 3632 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_rcb.c: In function 'hns_rcb_get_common_regs':
hisilicon/hns/hns_dsaf_rcb.c:970:1: error: the frame size of 2784 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_gmac.c: In function 'hns_gmac_get_regs':
hisilicon/hns/hns_dsaf_gmac.c:641:1: error: the frame size of 5728 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_rcb.c: In function 'hns_rcb_get_ring_regs':
hisilicon/hns/hns_dsaf_rcb.c:1021:1: error: the frame size of 2208 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_main.c: In function 'hns_dsaf_comm_init':
hisilicon/hns/hns_dsaf_main.c:1209:1: error: the frame size of 1904 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_xgmac.c: In function 'hns_xgmac_get_regs':
hisilicon/hns/hns_dsaf_xgmac.c:748:1: error: the frame size of 4704 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_main.c: In function 'hns_dsaf_update_stats':
hisilicon/hns/hns_dsaf_main.c:2420:1: error: the frame size of 1088 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
hisilicon/hns/hns_dsaf_main.c: In function 'hns_dsaf_get_regs':
hisilicon/hns/hns_dsaf_main.c:2753:1: error: the frame size of 10768 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
This does not seem to happen any more with gcc-7, but removing the ACCESS_ONCE
seems safe anyway and it avoids a serious issue for some people. I have verified
that with gcc-5.3.1, the object code we get is better in the new version
both with and without CONFIG_KASAN, as we no longer allocate a 1344 byte
stack frame for hns_dsaf_get_regs() but otherwise have practically identical
object code.
With gcc-7.0.0, removing ACCESS_ONCE has no effect, the object code is already
good either way.
This patch is probably not urgent to get into 4.11 as only KASAN=y builds
with certain compilers are affected, but I still think it makes sense to
backport into older kernels.
Cc: stable@vger.kernel.org
Fixes: 511e6bc ("net: add Hisilicon Network Subsystem DSAF support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
When for instance a mobile Linux device roams from one access point to
another with both APs sharing the same broadcast domain and a
multicast snooping switch in between:
1) (c) <~~~> (AP1) <--[SSW]--> (AP2)
2) (AP1) <--[SSW]--> (AP2) <~~~> (c)
Then currently IPv6 multicast packets will get lost for (c) until an
MLD Querier sends its next query message. The packet loss occurs
because upon roaming the Linux host so far stayed silent regarding
MLD and the snooping switch will therefore be unaware of the
multicast topology change for a while.
This patch fixes this by always resending MLD reports when an interface
change happens, for instance from NO-CARRIER to CARRIER state.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kalle Valo says:
====================
wireless-drivers fixes for 4.10
Only one important fix for rtlwifi which fixes a regression introduced
in 4.9 and which caused problems for many users.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Stephen Smalley
Linus Torvalds
Hugh Dickins
Xin Long
Vineet Gupta
Marcelo Ricardo Leitner
Benjamin Poirier
Eric Dumazet
David S. Miller
Ben Hutchings
Willem de Bruijn
Arnd Bergmann
Linus Lüssing