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Pull ext4 fixes from Ted Ts'o:
"Some miscellaneous ext4 fixes for 4.18; one fix is for a regression
introduced in 4.18-rc4.
Sorry for the late-breaking pull. I was originally going to wait for
the next merge window, but Eric Whitney found a regression introduced
in 4.18-rc4, so I decided to push out the regression plus the other
fixes now. (The other commits have been baking in linux-next since
early July)"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix check to prevent initializing reserved inodes
ext4: check for allocation block validity with block group locked
ext4: fix inline data updates with checksums enabled
ext4: clear mmp sequence number when remounting read-only
ext4: fix false negatives *and* false positives in ext4_check_descriptors()
Anatoly Trosinenko reports that a corrupted squashfs image can cause a
kernel oops. It turns out that squashfs can end up being confused about
negative fragment lengths.
The regular squashfs_read_data() does check for negative lengths, but
squashfs_read_metadata() did not, and the fragment size code just
blindly trusted the on-disk value. Fix both the fragment parsing and
the metadata reading code.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 8844618d8aa7: "ext4: only look at the bg_flags field if it is
valid" will complain if block group zero does not have the
EXT4_BG_INODE_ZEROED flag set. Unfortunately, this is not correct,
since a freshly created file system has this flag cleared. It gets
almost immediately after the file system is mounted read-write --- but
the following somewhat unlikely sequence will end up triggering a
false positive report of a corrupted file system:
mkfs.ext4 /dev/vdc
mount -o ro /dev/vdc /vdc
mount -o remount,rw /dev/vdc
Instead, when initializing the inode table for block group zero, test
to make sure that itable_unused count is not too large, since that is
the case that will result in some or all of the reserved inodes
getting cleared.
This fixes the failures reported by Eric Whiteney when running
generic/230 and generic/231 in the the nojournal test case.
Fixes: 8844618d8aa7 ("ext4: only look at the bg_flags field if it is valid")
Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull random fixes from Ted Ts'o:
"In reaction to the fixes to address CVE-2018-1108, some Linux
distributions that have certain systemd versions in some cases
combined with patches to libcrypt for FIPS/FEDRAMP compliance, have
led to boot-time stalls for some hardware.
The reaction by some distros and Linux sysadmins has been to install
packages that try to do complicated things with the CPU and hope that
leads to randomness.
To mitigate this, if RDRAND is available, mix it into entropy provided
by userspace. It won't hurt, and it will probably help"
* tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
random: mix rdrand with entropy sent in from userspace
With commit 044e6e3d74a3: "ext4: don't update checksum of new
initialized bitmaps" the buffer valid bit will get set without
actually setting up the checksum for the allocation bitmap, since the
checksum will get calculated once we actually allocate an inode or
block.
If we are doing this, then we need to (re-)check the verified bit
after we take the block group lock. Otherwise, we could race with
another process reading and verifying the bitmap, which would then
complain about the checksum being invalid.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1780137
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Pull GPIO fixes from Linus Walleij:
"Just a smallish OF fix and a driver fix:
- OF flag fix for special regulator flags
- fix up the Uniphier IRQ callback"
* tag 'gpio-v4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: uniphier: set legitimate irq trigger type in .to_irq hook
gpio: of: Handle fixed regulator flags properly
Fedora has integrated the jitter entropy daemon to work around slow
boot problems, especially on VM's that don't support virtio-rng:
https://bugzilla.redhat.com/show_bug.cgi?id=1572944
It's understandable why they did this, but the Jitter entropy daemon
works fundamentally on the principle: "the CPU microarchitecture is
**so** complicated and we can't figure it out, so it *must* be
random". Yes, it uses statistical tests to "prove" it is secure, but
AES_ENCRYPT(NSA_KEY, COUNTER++) will also pass statistical tests with
flying colors.
So if RDRAND is available, mix it into entropy submitted from
userspace. It can't hurt, and if you believe the NSA has backdoored
RDRAND, then they probably have enough details about the Intel
microarchitecture that they can reverse engineer how the Jitter
entropy daemon affects the microarchitecture, and attack its output
stream. And if RDRAND is in fact an honest DRNG, it will immeasurably
improve on what the Jitter entropy daemon might produce.
This also provides some protection against someone who is able to read
or set the entropy seed file.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
The inline data code was updating the raw inode directly; this is
problematic since if metadata checksums are enabled,
ext4_mark_inode_dirty() must be called to update the inode's checksum.
In addition, the jbd2 layer requires that get_write_access() be called
before the metadata buffer is modified. Fix both of these problems.
https://bugzilla.kernel.org/show_bug.cgi?id=200443
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Pull MIPS fix from Paul Burton:
"Here's one more MIPS fix, reverting an errata workaround that was
merged for v4.18-rc2 but has since been found to cause system hangs on
some BCM4718A1-based systems by the OpenWRT project"
* tag 'mips_fixes_4.18_5' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
Revert "MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum"
If a GPIO chip is a part of a hierarchy IRQ domain, there is no
way to specify the trigger type when gpio(d)_to_irq() allocates an
interrupt on-the-fly.
Currently, uniphier_gpio_to_irq() sets IRQ_TYPE_NONE, but it causes
an error in the .alloc() hook of the parent domain.
(drivers/irq/irq-uniphier-aidet.c)
Even if we change irq-uniphier-aidet.c to accept the NONE type,
GIC complains about it since commit 83a86fbb5b56 ("irqchip/gic:
Loudly complain about the use of IRQ_TYPE_NONE").
Instead, use IRQ_TYPE_LEVEL_HIGH as a temporary value when an irq
is allocated. irq_set_irq_type() will override it when the irq is
really requested.
Fixes: dbe776c2ca54 ("gpio: uniphier: add UniPhier GPIO controller driver")
Reported-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Previously, when an MMP-protected file system is remounted read-only,
the kmmpd thread would exit the next time it woke up (a few seconds
later), without resetting the MMP sequence number back to
EXT4_MMP_SEQ_CLEAN.
Fix this by explicitly killing the MMP thread when the file system is
remounted read-only.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Andreas Dilger <adilger@dilger.ca>
Pull i2c fixes from Wolfram Sang:
"Some driver bugfixes"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: imx: use open drain for recovery GPIO
i2c: rcar: handle RXDMA HW behaviour on Gen3
i2c: imx: Fix reinit_completion() use
i2c: davinci: Avoid zero value of CLKH
This reverts commit 2a027b47dba6 ("MIPS: BCM47XX: Enable 74K Core
ExternalSync for PCIe erratum").
Enabling ExternalSync caused a regression for BCM4718A1 (used e.g. in
Netgear E3000 and ASUS RT-N16): it simply hangs during PCIe
initialization. It's likely that BCM4717A1 is also affected.
I didn't notice that earlier as the only BCM47XX devices with PCIe I
own are:
1) BCM4706 with 2 x 14e4:4331
2) BCM4706 with 14e4:4360 and 14e4:4331
it appears that BCM4706 is unaffected.
While BCM5300X-ES300-RDS.pdf seems to document that erratum and its
workarounds (according to quotes provided by Tokunori) it seems not even
Broadcom follows them.
According to the provided info Broadcom should define CONF7_ES in their
SDK's mipsinc.h and implement workaround in the si_mips_init(). Checking
both didn't reveal such code. It *could* mean Broadcom also had some
problems with the given workaround.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Reported-by: Michael Marley <michael@michaelmarley.com>
Patchwork: https://patchwork.linux-mips.org/patch/20032/
URL: https://bugs.openwrt.org/index.php?do=details&task_id=1688
Cc: Tokunori Ikegami <ikegami@allied-telesis.co.jp>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
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