ip_check_defrag() might be called from af_packet within the
RX path where shared SKBs are used, so it must not modify
the input SKB before it has unshared it for defragmentation.
Use skb_copy_bits() to get the IP header and only pull in
everything later.
The same is true for the other caller in macvlan as it is
called from dev->rx_handler which can also get a shared SKB.
Reported-by: Eric Leblond <eric@regit.org>
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add logic to verify that a port comparison byte code operation
actually has the second inet_diag_bc_op from which we read the port
for such operations.
Previously the code blindly referenced op[1] without first checking
whether a second inet_diag_bc_op struct could fit there. So a
malicious user could make the kernel read 4 bytes beyond the end of
the bytecode array by claiming to have a whole port comparison byte
code (2 inet_diag_bc_op structs) when in fact the bytecode was not
long enough to hold both.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add logic to check the address family of the user-supplied conditional
and the address family of the connection entry. We now do not do
prefix matching of addresses from different address families (AF_INET
vs AF_INET6), except for the previously existing support for having an
IPv4 prefix match an IPv4-mapped IPv6 address (which this commit
maintains as-is).
This change is needed for two reasons:
(1) The addresses are different lengths, so comparing a 128-bit IPv6
prefix match condition to a 32-bit IPv4 connection address can cause
us to unwittingly walk off the end of the IPv4 address and read
garbage or oops.
(2) The IPv4 and IPv6 address spaces are semantically distinct, so a
simple bit-wise comparison of the prefixes is not meaningful, and
would lead to bogus results (except for the IPv4-mapped IPv6 case,
which this commit maintains).
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add logic to validate INET_DIAG_BC_S_COND and INET_DIAG_BC_D_COND
operations.
Previously we did not validate the inet_diag_hostcond, address family,
address length, and prefix length. So a malicious user could make the
kernel read beyond the end of the bytecode array by claiming to have a
whole inet_diag_hostcond when the bytecode was not long enough to
contain a whole inet_diag_hostcond of the given address family. Or
they could make the kernel read up to about 27 bytes beyond the end of
a connection address by passing a prefix length that exceeded the
length of addresses of the given family.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix inet_diag to be aware of the fact that AF_INET6 TCP connections
instantiated for IPv4 traffic and in the SYN-RECV state were actually
created with inet_reqsk_alloc(), instead of inet6_reqsk_alloc(). This
means that for such connections inet6_rsk(req) returns a pointer to a
random spot in memory up to roughly 64KB beyond the end of the
request_sock.
With this bug, for a server using AF_INET6 TCP sockets and serving
IPv4 traffic, an inet_diag user like `ss state SYN-RECV` would lead to
inet_diag_fill_req() causing an oops or the export to user space of 16
bytes of kernel memory as a garbage IPv6 address, depending on where
the garbage inet6_rsk(req) pointed.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit c702418f8a ("mm: vmscan: do not keep kswapd looping forever due
to individual uncompactable zones") removed zone watermark checks from
the compaction code in kswapd but left in the zone congestion clearing,
which now happens unconditionally on higher order reclaim.
This messes up the reclaim throttling logic for zones with
dirty/writeback pages, where zones should only lose their congestion
status when their watermarks have been restored.
Remove the clearing from the zone compaction section entirely. The
preliminary zone check and the reclaim loop in kswapd will clear it if
the zone is considered balanced.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The direct-IO write path already had the i_size checks in mm/filemap.c,
but it turns out the read path did not, and removing the block size
checks in fs/block_dev.c (commit bbec0270bd: "blkdev_max_block: make
private to fs/buffer.c") removed the magic "shrink IO to past the end of
the device" code there.
Fix it by truncating the IO to the size of the block device, like the
write path already does.
NOTE! I suspect the write path would be *much* better off doing it this
way in fs/block_dev.c, rather than hidden deep in mm/filemap.c. The
mm/filemap.c code is extremely hard to follow, and has various
conditionals on the target being a block device (ie the flag passed in
to 'generic_write_checks()', along with a conditional update of the
inode timestamp etc).
It is also quite possible that we should treat this whole block device
size as a "s_maxbytes" issue, and try to make the logic even more
generic. However, in the meantime this is the fairly minimal targeted
fix.
Noted by Milan Broz thanks to a regression test for the cryptsetup
reencrypt tool.
Reported-and-tested-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking fixes from David Miller:
"Two stragglers:
1) The new code that adds new flushing semantics to GRO can cause SKB
pointer list corruption, manage the lists differently to avoid the
OOPS. Fix from Eric Dumazet.
2) When TCP fast open does a retransmit of data in a SYN-ACK or
similar, we update retransmit state that we shouldn't triggering a
WARN_ON later. Fix from Yuchung Cheng."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
net: gro: fix possible panic in skb_gro_receive()
tcp: bug fix Fast Open client retransmission
commit 2e71a6f808 (net: gro: selective flush of packets) added
a bug for skbs using frag_list. This part of the GRO stack is rarely
used, as it needs skb not using a page fragment for their skb->head.
Most drivers do use a page fragment, but some of them use GFP_KERNEL
allocations for the initial fill of their RX ring buffer.
napi_gro_flush() overwrite skb->prev that was used for these skb to
point to the last skb in frag_list.
Fix this using a separate field in struct napi_gro_cb to point to the
last fragment.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If SYN-ACK partially acks SYN-data, the client retransmits the
remaining data by tcp_retransmit_skb(). This increments lost recovery
state variables like tp->retrans_out in Open state. If loss recovery
happens before the retransmission is acked, it triggers the WARN_ON
check in tcp_fastretrans_alert(). For example: the client sends
SYN-data, gets SYN-ACK acking only ISN, retransmits data, sends
another 4 data packets and get 3 dupacks.
Since the retransmission is not caused by network drop it should not
update the recovery state variables. Further the server may return a
smaller MSS than the cached MSS used for SYN-data, so the retranmission
needs a loop. Otherwise some data will not be retransmitted until timeout
or other loss recovery events.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes a regression in 3.7-rc, which has since gone into stable.
Commit 00442ad04a ("mempolicy: fix a memory corruption by refcount
imbalance in alloc_pages_vma()") changed get_vma_policy() to raise the
refcount on a shmem shared mempolicy; whereas shmem_alloc_page() went
on expecting alloc_page_vma() to drop the refcount it had acquired.
This deserves a rework: but for now fix the leak in shmem_alloc_page().
Hugh: shmem_swapin() did not need a fix, but surely it's clearer to use
the same refcounting there as in shmem_alloc_page(), delete its onstack
mempolicy, and the strange mpol_cond_copy() and __mpol_cond_copy() -
those were invented to let swapin_readahead() make an unknown number of
calls to alloc_pages_vma() with one mempolicy; but since 00442ad04a,
alloc_pages_vma() has kept refcount in balance, so now no problem.
Reported-and-tested-by: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a zone meets its high watermark and is compactable in case of
higher order allocations, it contributes to the percentage of the node's
memory that is considered balanced.
This requirement, that a node be only partially balanced, came about
when kswapd was desparately trying to balance tiny zones when all bigger
zones in the node had plenty of free memory. Arguably, the same should
apply to compaction: if a significant part of the node is balanced
enough to run compaction, do not get hung up on that tiny zone that
might never get in shape.
When the compaction logic in kswapd is reached, we know that at least
25% of the node's memory is balanced properly for compaction (see
zone_balanced and pgdat_balanced). Remove the individual zone checks
that restart the kswapd cycle.
Otherwise, we may observe more endless looping in kswapd where the
compaction code loops back to reclaim because of a single zone and
reclaim does nothing because the node is considered balanced overall.
See for example
https://bugzilla.redhat.com/show_bug.cgi?id=866988
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-and-tested-by: Thorsten Leemhuis <fedora@leemhuis.info>
Reported-by: Jiri Slaby <jslaby@suse.cz>
Tested-by: John Ellson <john.ellson@comcast.net>
Tested-by: Zdenek Kabelac <zkabelac@redhat.com>
Tested-by: Bruno Wolff III <bruno@wolff.to>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 0bf380bc70 ("mm: compaction: check pfn_valid when entering a
new MAX_ORDER_NR_PAGES block during isolation for migration") added a
check for pfn_valid() when isolating pages for migration as the scanner
does not necessarily start pageblock-aligned.
Since commit c89511ab2f ("mm: compaction: Restart compaction from near
where it left off"), the free scanner has the same problem. This patch
makes sure that the pfn range passed to isolate_freepages_block() is
within the same block so that pfn_valid() checks are unnecessary.
In answer to Henrik's wondering why others have not reported this:
reproducing this requires a large enough hole with the right aligment to
have compaction walk into a PFN range with no memmap. Size and
alignment depends in the memory model - 4M for FLATMEM and 128M for
SPARSEMEM on x86. It needs a "lucky" machine.
Reported-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On some systems, e.g., kzm9g, MMCIF interfaces can produce spurious
interrupts without any active request. To prevent the Oops, that results
in such cases, don't dereference the mmc request pointer until we make
sure, that we are indeed processing such a request.
Reported-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
Cc: stable@vger.kernel.org
Signed-off-by: Chris Ball <cjb@laptop.org>
This reverts commit 8464dd52d3, which was a misapplied debugging
version of the patch, not the final patch itself.
Signed-off-by: Chris Ball <cjb@laptop.org>
Cc: stable@vger.kernel.org
2abeb5c5de ("Add clk_(enable/disable) in runtime suspend/resume")
added the capability to stop the clocks when the device is runtime
suspended, but forgot to handle the case of the card-detect using
an external gpio.
Therefore in the case that runtime-pm is enabled, start the io-clock
when a card is inserted and stop it again once it is removed.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Pull MIPS fixes from Ralf Baechle:
"These are the fixes for the N32 syscall bugs found by Al, an
extraneous break that broke detection for R3000 and R3081 processors,
an endless loop processing signals for kernel task (x86 received the
same fix a while ago) and a fix for transparent huge page which took
ages to track down because it was so hard to come up with a workable
test case."
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: Fix endless loop when processing signals for kernel tasks
MIPS: R3000/R3081: Fix CPU detection.
MIPS: N32: Fix signalfd4 syscall entry point
MIPS: N32: Fix preadv(2) and pwritev(2) entry points.
MIPS: Avoid mcheck by flushing page range in huge_ptep_set_access_flags()
Pull build fix from Rusty Russell:
"Tim Gardner <tim.gardner@canonical.com> writes:
> It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c.
> The object file cannot be built until $(obj)/oid_registry_data.c has been
> generated.
>
> A periodic and hard to reproduce parallel build failure is due to
> this incorrect lib/Makefile dependency. The compile error is completely
> disingenuous.
>
> GEN lib/oid_registry_data.c
> Compiling 49 OIDs
> CC lib/oid_registry.o
> gcc: error: lib/oid_registry.c: No such file or directory
> gcc: fatal error: no input files
> compilation terminated.
> make[3]: *** [lib/oid_registry.o] Error 4
I can't reproduce it either. It's completely weird; nothing ever
removes lib/oid_registry.c, so either gcc is giving the wrong message
or it's a weird fs with a very odd race.
But your version is definitely more correct than the previous one,
so..."
* 'more-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
lib/Makefile: Fix oid_registry build dependency
Pull module signing fixes from Rusty Russell:
"David gave me these a month ago, during my git workflow churn :("
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
ASN.1: Fix an indefinite length skip error
MODSIGN: Don't use enum-type bitfields in module signature info block
Pull watchdog fix from Thomas Gleixner:
"Trivial CPU hotplug regression fix for the watchdog code"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
watchdog: Fix CPU hotplug regression
It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c.
The object file cannot be built until $(obj)/oid_registry_data.c has been
generated.
A periodic and hard to reproduce parallel build failure is due to
this incorrect lib/Makefile dependency. The compile error is completely
disingenuous.
GEN lib/oid_registry_data.c
Compiling 49 OIDs
CC lib/oid_registry.o
gcc: error: lib/oid_registry.c: No such file or directory
gcc: fatal error: no input files
compilation terminated.
make[3]: *** [lib/oid_registry.o] Error 4
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The problem occurs [1] when a kernel-mode task returns from a system
call with a pending signal.
A real-life scenario is a child of 'khelper' returning from a failed
kernel_execve() in ____call_usermodehelper() [ kernel/kmod.c ].
kernel_execve() fails due to a pending SIGKILL, which is the result of
"kill -9 -1" (at least, busybox's init does it upon reboot).
The loop is as follows:
* syscall_exit_work:
- work_pending: // start_of_the_loop
- work_notifysig:
- do_notify_resume()
- do_signal()
- if (!user_mode(regs)) return;
- resume_userspace // TIF_SIGPENDING is still set
- work_pending // so we call work_pending => goto
// start_of_the_loop
More information can be found in another LKML thread:
http://www.serverphorums.com/read.php?12,457826
[1] The problem was also reproduced on !CONFIG_VM86 x86, and the
following fix was accepted.
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=29a2e2836ff9ea65a603c89df217f4198973a74f
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3571/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Broken since e05ea74fc56f347f872ef9946d27c53e8bf20864 (lmo) rsp.
cea7e2dfde (kernel.org) [MIPS: Sort out CPU
type to name translation.] These CPUs are no longer very popular to say
the least ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Murphy McCauley <murphy.mccauley@gmail.com>
This needs to use the compat entry point or it's going to fail on big
endian systems.
Noticed by Al Viro.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Johannes Berg
Neal Cardwell
Johannes Weiner
Linus Torvalds
Eric Dumazet
Yuchung Cheng
Mel Gorman
Guennadi Liakhovetski
Chris Ball
Heiko Stübner
Tim Gardner
Dmitry Adamushko
Ralf Baechle