Instead of (or in addition to) kernel module signing, being able to reason
about the origin of a kernel module would be valuable in situations
where an OS already trusts a specific file system, file, etc, due to
things like security labels or an existing root of trust to a partition
through things like dm-verity.
This introduces a new syscall (currently only on x86), similar to
init_module, that has only two arguments. The first argument is used as
a file descriptor to the module and the second argument is a pointer to
the NULL terminated string of module arguments.
Signed-off-by: Kees Cook <keescook@chromium.org>
[accepted into Rusty's modules-wip tree for linux-next:
http://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=shortlog;h=refs/heads/modules-wip]
BUG=chromium-os:34134
TEST=parrot build, manual testing
Change-Id: I51122d61d0085ed40d2ac9b542646b28d066d5e3
Reviewed-on: https://gerrit.chromium.org/gerrit/34302
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Commit-Ready: Kees Cook <keescook@chromium.org>
Before, device booted only with charger plugged in and showed 0%. Source wasn't ok to handle sec-fuelgauge correctly.
Change-Id: If19ed4877fc965c588e65a2deef3977a192aa30a
* This principally was identified when the R recovery started
issuing reboot commands such as "userrequested,recovery" or
"userrequested,fastboot". While it's not 100% clear that
userrequested is supposed to be followed by a reboot *source* as
opposed to a target, it illuminated the fact that our kernel gets
stuck rebooting to the same target/reason when an unknown command
is issued.
* It seems much more logical to normal people that the kernel go ahead
and reboot to the "normal" (read: Android system) target when the
one passed to the kernel isn't known, as opposed to getting stuck
in something like recovery forever.
Change-Id: Id63a31c9855b72955b89694ecac522e6569d84ac
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
We already use them for openat() and friends, but fstat() also wants to
be able to use O_PATH file descriptors. This should make it more
directly comparable to the O_SEARCH of Solaris.
Note that you could already do the same thing with "fstatat()" and an
empty path, but just doing "fstat()" directly is simpler and faster, so
there is no reason not to just allow it directly.
See also commit 332a2e1244bd, which did the same thing for fchdir, for
the same reasons.
Reported-by: ольга крыжановская <olga.kryzhanovska@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org # O_PATH introduced in 3.0+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: I98db77b7f3fcadb1f0ecdb5c50ff4a7ad9db8bb3
Update the set of SELinux netlink socket class definitions to match
the set of netlink protocols implemented by the kernel. The
ip_queue implementation for the NETLINK_FIREWALL and NETLINK_IP6_FW protocols
was removed in d16cf20e2f2f13411eece7f7fb72c17d141c4a84, so we can remove
the corresponding class definitions as this is dead code. Add new
classes for NETLINK_ISCSI, NETLINK_FIB_LOOKUP, NETLINK_CONNECTOR,
NETLINK_NETFILTER, NETLINK_GENERIC, NETLINK_SCSITRANSPORT, NETLINK_RDMA,
and NETLINK_CRYPTO so that we can distinguish among sockets created
for each of these protocols. This change does not define the finer-grained
nlsmsg_read/write permissions or map specific nlmsg_type values to those
permissions in the SELinux nlmsgtab; if finer-grained control of these
sockets is desired/required, that can be added as a follow-on change.
We do not define a SELinux class for NETLINK_ECRYPTFS as the implementation
was removed in 624ae52845.
Change-Id: Ic233c39d4271544a3a63f9fa64c855a44fc08705
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Remove unused permission definitions from SELinux.
Many of these were only ever used in pre-mainline
versions of SELinux, prior to Linux 2.6.0. Some of them
were used in the legacy network or compat_net=1 checks
that were disabled by default in Linux 2.6.18 and
fully removed in Linux 2.6.30.
Permissions never used in mainline Linux:
file swapon
filesystem transition
tcp_socket { connectto newconn acceptfrom }
node enforce_dest
unix_stream_socket { newconn acceptfrom }
Legacy network checks, removed in 2.6.30:
socket { recv_msg send_msg }
node { tcp_recv tcp_send udp_recv udp_send rawip_recv rawip_send dccp_recv dccp_send }
netif { tcp_recv tcp_send udp_recv udp_send rawip_recv rawip_send dccp_recv dccp_send }
Change-Id: I976d81760be7a800d696afb9ffc6c7a5dafa5c69
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>
This avoids a (harmless) error:
<3>[ 0.214144] msm_thermal:msm_thermal_get_freq_table error reading cpufreq table
Change-Id: Ibf8e319751edb49e836b2e207c0075f60b71f44a
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
commit ec91e78d378cc5d4b43805a1227d8e04e5dfa17d upstream.
Commit e49ce14150 ("modpost: use linker section to generate table.")
was not so cool as we had expected first; it ended up with ugly section
hacks when commit dd2a3acaec ("mod/file2alias: make modpost compile
on darwin again") came in.
Given a certain degree of unknowledge about the link stage of host
programs, I really want to see simple, stupid table lookup so that
this works in the same way regardless of the underlying executable
format.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Mathieu Malaterre <malat@debian.org>
[nc: Omit rpmsg, sdw, fslmc, tbsvc, and typec as they don't exist here
Add of to avoid backporting two larger patches]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
Change-Id: Ic632eaa7777338109f80c76535e67917f5b9761c
Use the target compiler to compute the offsets for the fields of the
device_id structures, so that it won't be broken by different alignments
between the host and target ABIs.
This also fixes missing endian corrections for some modaliases.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
Change-Id: I7c668febca617504e73ca0796cdcaedde4c0d72d
- Disabled increasing VDDMAX in qpnp-charger
- Fixed non-charging issue after flashlight has been turned off while charging
- Enabled battery swelling protection (CONFIG_BATTERY_SWELLING) in sec-battery to s3ve3g devices (proper configs are defined in battery header already)
- Enabled prevent SOC jump. The battery driver will slowly add a SOC until it's 100 when the average current is below 170 and min SOC is 93
- Reduced minimum expected full condition SOC from 95 to 93
- Removed 'ext-ovp-present' bool from device tree as only qpnp-sec-charger calls it
- Reworked default high battery temperature threshold/recovery (60°C/47°C to 58°C/53°C) also while in LPM
- Switched from Qualcomm's flash-boot-supply to Samsung's flash regulator disabler/enabler
- Switched from time measure check type (2400 mins) to current check type (<170mA) while charging to report full charged condition
Change-Id: Id74e3d9497d381a389ae56096c61dfa7200a83cf
Structures in shared memory that can be modified by remote
processors may have untrusted values, they should be validated
before use.
Adding proper validation before using fields of shared
structures.
CRs-Fixed: 2421602
Change-Id: I947ed5b0fe5705e5223d75b0ea8aafb36113ca5a
Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
[haggertk: Backport to 3.4/msm8974. Adjust context]
CVE-2019-10527
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
commit 68035c80e129c4cfec659aac4180354530b26527 upstream.
Way back in 2017, fuzzing the 4.14-rc2 USB stack with syzkaller kicked
up the following WARNING from the UVC chain scanning code:
| list_add double add: new=ffff880069084010, prev=ffff880069084010,
| next=ffff880067d22298.
| ------------[ cut here ]------------
| WARNING: CPU: 1 PID: 1846 at lib/list_debug.c:31 __list_add_valid+0xbd/0xf0
| Modules linked in:
| CPU: 1 PID: 1846 Comm: kworker/1:2 Not tainted
| 4.14.0-rc2-42613-g1488251d1a98 #238
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
| Workqueue: usb_hub_wq hub_event
| task: ffff88006b01ca40 task.stack: ffff880064358000
| RIP: 0010:__list_add_valid+0xbd/0xf0 lib/list_debug.c:29
| RSP: 0018:ffff88006435ddd0 EFLAGS: 00010286
| RAX: 0000000000000058 RBX: ffff880067d22298 RCX: 0000000000000000
| RDX: 0000000000000058 RSI: ffffffff85a58800 RDI: ffffed000c86bbac
| RBP: ffff88006435dde8 R08: 1ffff1000c86ba52 R09: 0000000000000000
| R10: 0000000000000002 R11: 0000000000000000 R12: ffff880069084010
| R13: ffff880067d22298 R14: ffff880069084010 R15: ffff880067d222a0
| FS: 0000000000000000(0000) GS:ffff88006c900000(0000) knlGS:0000000000000000
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
| CR2: 0000000020004ff2 CR3: 000000006b447000 CR4: 00000000000006e0
| Call Trace:
| __list_add ./include/linux/list.h:59
| list_add_tail+0x8c/0x1b0 ./include/linux/list.h:92
| uvc_scan_chain_forward.isra.8+0x373/0x416
| drivers/media/usb/uvc/uvc_driver.c:1471
| uvc_scan_chain drivers/media/usb/uvc/uvc_driver.c:1585
| uvc_scan_device drivers/media/usb/uvc/uvc_driver.c:1769
| uvc_probe+0x77f2/0x8f00 drivers/media/usb/uvc/uvc_driver.c:2104
Looking into the output from usbmon, the interesting part is the
following data packet:
ffff880069c63e00 30710169 C Ci:1:002:0 0 143 = 09028f00 01030080
00090403 00000e01 00000924 03000103 7c003328 010204db
If we drop the lead configuration and interface descriptors, we're left
with an output terminal descriptor describing a generic display:
/* Output terminal descriptor */
buf[0] 09
buf[1] 24
buf[2] 03 /* UVC_VC_OUTPUT_TERMINAL */
buf[3] 00 /* ID */
buf[4] 01 /* type == 0x0301 (UVC_OTT_DISPLAY) */
buf[5] 03
buf[6] 7c
buf[7] 00 /* source ID refers to self! */
buf[8] 33
The problem with this descriptor is that it is self-referential: the
source ID of 0 matches itself! This causes the 'struct uvc_entity'
representing the display to be added to its chain list twice during
'uvc_scan_chain()': once via 'uvc_scan_chain_entity()' when it is
processed directly from the 'dev->entities' list and then again
immediately afterwards when trying to follow the source ID in
'uvc_scan_chain_forward()'
Add a check before adding an entity to a chain list to ensure that the
entity is not already part of a chain.
Link: https://lore.kernel.org/linux-media/CAAeHK+z+Si69jUR+N-SjN9q4O+o5KFiNManqEa-PjUta7EOb7A@mail.gmail.com/
Fixes: c0efd23292 ("V4L/DVB (8145a): USB Video Class driver")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[haggertk: Backport to 3.4. Adjust context]
CVE-2020-0404
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
Change-Id: I0aadd69e56b56251cd71c6effebbab2ba78ec05c
Samsung has introduced this since Lollipop Release and due to this the Capacitive Keys had issues and stopped working repeatedly once screen is locked.
It only works again after reboot and fails after screen is locked.
Disabling this has fixed Capacitive Key Issue.
Change-Id: Ia7ff76620cdac863289f57ea37459bd5b94ea99e
Signed-off-by: Jackeagle <jackeagle102@gmail.com>
This commit brings up the support for sec-battery and qpnp-charger drivers to s3ve3g devices.
Old qpnp-sec-charger driver, a heavily modified qpnp-charger driver by Samsung, caused internal issues such as no CPU deep sleep on Android 6.0+.
Following nodes will be removed:
/sys/module/qpnp_sec_charger
Following nodes will be added:
/sys/class/power_supply/pogo
/sys/class/power_supply/ps
/sys/class/power_supply/qpnp-chg
/sys/class/power_supply/wireless
/sys/module/qpnp_charger
Requires Samsung's charger_monitor binary with proper permissions set to nodes (see above) at init to interact with userspace
Change-Id: I1af484378b3a8dc6c3819a8670852be433131f32
Function qpnp_flash_regulator_operate loops led_array in 3 (almost) equivalent for-loops to enable flash (wa) regulator, however this isn't needed as the first loop does enable the regulators at first try already. With this changes we don't need change_boost_control function anymore as defined in qpnp-sec-charger to re-enable charging feature.
Additional improvements and fixes from official Samsung sources.
Change-Id: I0d325d96771e2d62bc87824adddf4c6b3db26ffd
[ Upstream commit afd07389d3f4933c7f7817a92fb5e053d59a3182 ]
One of the vmalloc stress test case triggers the kernel BUG():
<snip>
[60.562151] ------------[ cut here ]------------
[60.562154] kernel BUG at mm/vmalloc.c:512!
[60.562206] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[60.562247] CPU: 0 PID: 430 Comm: vmalloc_test/0 Not tainted 4.20.0+ #161
[60.562293] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[60.562351] RIP: 0010:alloc_vmap_area+0x36f/0x390
<snip>
it can happen due to big align request resulting in overflowing of
calculated address, i.e. it becomes 0 after ALIGN()'s fixup.
Fix it by checking if calculated address is within vstart/vend range.
Link: http://lkml.kernel.org/r/20190124115648.9433-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I1fdcf1c817975bf21817d38e4cc34f93aad865f4
commit d02bd27bd33dd7e8d22594cd568b81be0cb584cd upstream.
Add a new field, VIRTIO_BALLOON_S_AVAIL, to virtio_balloon memory
statistics protocol, corresponding to 'Available' in /proc/meminfo.
It indicates to the hypervisor how big the balloon can be inflated
without pushing the guest system to swap. This metric would be very
useful in VM orchestration software to improve memory management of
different VMs under overcommit.
This patch (of 2):
Factor out calculation of the available memory counter into a separate
exportable function, in order to be able to use it in other parts of the
kernel.
In particular, it appears a relevant metric to report to the hypervisor
via virtio-balloon statistics interface (in a followup patch).
Signed-off-by: Igor Redko <redkoi@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.4 as dependency of commit a1078e821b60
"xen: let alloc_xenballooned_pages() fail if not enough memory free"]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Change-Id: Ib8cae94ddd9742752ecc795129be642c57f8cc15
Historically, we exported shared pages to userspace via sysinfo(2)
sharedram and /proc/meminfo's "MemShared" fields. With the advent of
tmpfs, from kernel v2.4 onward, that old way for accounting shared mem
was deemed inaccurate and we started to export a hard-coded 0 for
sysinfo.sharedram. Later on, during the 2.6 timeframe, "MemShared" got
re-introduced to /proc/meminfo re-branded as "Shmem", but we're still
reporting sysinfo.sharedmem as that old hard-coded zero, which makes the
"shared memory" report inconsistent across interfaces.
This patch leverages the addition of explicit accounting for pages used
by shmem/tmpfs -- "4b02108 mm: oom analysis: add shmem vmstat" -- in
order to make the users of sysinfo(2) and si_meminfo*() friends aware of
that vmstat entry and make them report it consistently across the
interfaces, as well to make sysinfo(2) returned data consistent with our
current API documentation states.
Change-Id: I51474973cc267ee368352e96e7229e0101f38aca
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many load balancing and workload placing programs check /proc/meminfo to
estimate how much free memory is available. They generally do this by
adding up "free" and "cached", which was fine ten years ago, but is
pretty much guaranteed to be wrong today.
It is wrong because Cached includes memory that is not freeable as page
cache, for example shared memory segments, tmpfs, and ramfs, and it does
not include reclaimable slab memory, which can take up a large fraction
of system memory on mostly idle systems with lots of files.
Currently, the amount of memory that is available for a new workload,
without pushing the system into swap, can be estimated from MemFree,
Active(file), Inactive(file), and SReclaimable, as well as the "low"
watermarks from /proc/zoneinfo.
However, this may change in the future, and user space really should not
be expected to know kernel internals to come up with an estimate for the
amount of free memory.
It is more convenient to provide such an estimate in /proc/meminfo. If
things change in the future, we only have to change it in one place.
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Erik Mouw <erik.mouw_2@nxp.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: I2361450da2d1af15643ff8b926d3afbea94c29f2
If an unprivileged user has the appropriate capabilities in their
current user namespace allow the creation of new namespaces.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Change-Id: Ic3bdabc878944a7f3da0f3293d7163f051e65c34
- Push the permission check from the core setns syscall into
the setns install methods where the user namespace of the
target namespace can be determined, and used in a ns_capable
call.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Change-Id: I655fbd54531112ae7fe425a4055c2583a41deb78
In the help text describing user namespaces recommend use of memory
control groups. In many cases memory control groups are the only
mechanism there is to limit how much memory a user who can create
user namespaces can use.
Change-Id: I43fe65bc91b6014cf314a76137b35d10037dc3d2
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
There are places in kernel like the lowmemorykiller which
invokes show_mem_call_notifiers from an atomic context.
So move from a blocking notifier to atomic. At present
the notifier callbacks does not call sleeping functions,
but it should be made sure, it does not happen in future also.
Change-Id: I9668e67463ab8a6a60be55dbc86b88f45be8b041
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
At present any vmpressure value is scaled up if the pages are
reclaimed through direct reclaim. This can result in false
vmpressure values. Consider a case where a device is booted up
and most of the memory is occuppied by file pages. kswapd will
make sure that high watermark is maintained. Now when a sudden
huge allocation request comes in, the system will definitely
have to get into direct reclaims. The vmpressures can be very low,
but because of allocstall accounting logic even these low values
will be scaled to values nearing 100. This can resulting in
unnecessary LMK kills for example.
Change-Id: Idd7c6724264ac89f1f68f2e9d70a32390ffca3e5
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
The existing calculation of vmpressure takes into account only
the ratio of reclaimed to scanned pages, but not the time spent
or the difficulty in reclaiming those pages. For e.g. when there
are quite a number of file pages in the system, an allocation
request can be satisfied by reclaiming the file pages alone. If
such a reclaim is succesful, the vmpressure value will remain low
irrespective of the time spent by the reclaim code to free up the
file pages. With a feature like lowmemorykiller, killing a task
can be faster than reclaiming the file pages alone. So if the
vmpressure values reflect the reclaim difficulty level, clients
can make a decision based on that, for e.g. to kill a task early.
This patch monitors the number of pages scanned in the direct
reclaim path and scales the vmpressure level according to that.
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Change-Id: I6e643d29a9a1aa0814309253a8b690ad86ec0b13
There's a bunch of failure exits in ffs_fs_mount() with
seriously broken recovery logics. Most of that appears to stem
from misunderstanding of the ->kill_sb() semantics; unlike
->put_super() it is called for *all* superblocks of given type,
no matter how (in)complete the setup had been. ->put_super()
is called only if ->s_root is not NULL; any failure prior to
setting ->s_root will have the call of ->put_super() skipped.
->kill_sb(), OTOH, awaits every superblock that has come from
sget().
Current behaviour of ffs_fs_mount():
We have struct ffs_sb_fill_data data on stack there. We do
ffs_dev = functionfs_acquire_dev_callback(dev_name);
and store that in data.private_data. Then we call mount_nodev(),
passing it ffs_sb_fill() as a callback. That will either fail
outright, or manage to call ffs_sb_fill(). There we allocate an
instance of struct ffs_data, slap the value of ffs_dev (picked
from data.private_data) into ffs->private_data and overwrite
data.private_data by storing ffs into an overlapping member
(data.ffs_data). Then we store ffs into sb->s_fs_info and attempt
to set the rest of the things up (root inode, root dentry, then
create /ep0 there). Any of those might fail. Should that
happen, we get ffs_fs_kill_sb() called before mount_nodev()
returns. If mount_nodev() fails for any reason whatsoever,
we proceed to
functionfs_release_dev_callback(data.ffs_data);
That's broken in a lot of ways. Suppose the thing has failed in
allocation of e.g. root inode or dentry. We have
functionfs_release_dev_callback(ffs);
ffs_data_put(ffs);
done by ffs_fs_kill_sb() (ffs accessed via sb->s_fs_info), followed by
functionfs_release_dev_callback(ffs);
from ffs_fs_mount() (via data.ffs_data). Note that the second
functionfs_release_dev_callback() has every chance to be done to freed memory.
Suppose we fail *before* root inode allocation. What happens then?
ffs_fs_kill_sb() doesn't do anything to ffs (it's either not called at all,
or it doesn't have a pointer to ffs stored in sb->s_fs_info). And
functionfs_release_dev_callback(data.ffs_data);
is called by ffs_fs_mount(), but here we are in nasal daemon country - we
are reading from a member of union we'd never stored into. In practice,
we'll get what we used to store into the overlapping field, i.e. ffs_dev.
And then we get screwed, since we treat it (struct gfs_ffs_obj * in
disguise, returned by functionfs_acquire_dev_callback()) as struct
ffs_data *, pick what would've been ffs_data ->private_data from it
(*well* past the actual end of the struct gfs_ffs_obj - struct ffs_data
is much bigger) and poke in whatever it points to.
FWIW, there's a minor leak on top of all that in case if ffs_sb_fill()
fails on kstrdup() - ffs is obviously forgotten.
The thing is, there is no point in playing all those games with union.
Just allocate and initialize ffs_data *before* calling mount_nodev() and
pass a pointer to it via data.ffs_data. And once it's stored in
sb->s_fs_info, clear data.ffs_data, so that ffs_fs_mount() knows that
it doesn't need to kill the sucker manually - from that point on
we'll have it done by ->kill_sb().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: stable <stable@vger.kernel.org> # 3.3+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: Ic3886c79018e4f06cf84d27c98ce5f80d7d9bbe9
Signed-off-by: Nolen Johnson <johnsonnolen@gmail.com>
MTP usb device node created as a part of mtp function init call.
Userspace can read/write to MTP device using this node. If MTP is
not enabled in the composition and trying to read mtp_usb dev node
from the userspace leading to null pointer access in mtp_read.
Do not access ep OUT maxpacket size in mtp_read. First block on mtp_read
until the state become online which doesn't wakeup from the thread and
expecting for the read completion or state change which occurs as
a part of set_alt.
Change-Id: Icbee5fe7ae2c02b2bca185a0dc7587eb4940058a
Signed-off-by: ChandanaKishori Chiluveru <cchilu@codeaurora.org>
Signed-off-by: Azhar Shaikh <azhars@codeaurora.org>
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
Commit 9183df25fe7b ("shm: add memfd_create() syscall") added a new
system call (memfd_create) but didn't update the asm-generic unistd
header.
This patch adds the new system call to the asm-generic version of
unistd.h so that it can be used by architectures such as arm64.
Change-Id: I5052b538f84ffc1d4ca9799b19147e387610f1ba
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
If we set SEAL_WRITE on a file, we must make sure there cannot be any
ongoing write-operations on the file. For write() calls, we simply lock
the inode mutex, for mmap() we simply verify there're no writable
mappings. However, there might be pages pinned by AIO, Direct-IO and
similar operations via GUP. We must make sure those do not write to the
memfd file after we set SEAL_WRITE.
As there is no way to notify GUP users to drop pages or to wait for them
to be done, we implement the wait ourself: When setting SEAL_WRITE, we
check all pages for their ref-count. If it's bigger than 1, we know
there's some user of the page. We then mark the page and wait for up to
150ms for those ref-counts to be dropped. If the ref-counts are not
dropped in time, we refuse the seal operation.
Change-Id: I964c29a82f2a9a1077647b29b2073c9ef4e0a05a
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memfd_create() is similar to mmap(MAP_ANON), but returns a file-descriptor
that you can pass to mmap(). It can support sealing and avoids any
connection to user-visible mount-points. Thus, it's not subject to quotas
on mounted file-systems, but can be used like malloc()'ed memory, but with
a file-descriptor to it.
memfd_create() returns the raw shmem file, so calls like ftruncate() can
be used to modify the underlying inode. Also calls like fstat() will
return proper information and mark the file as regular file. If you want
sealing, you can specify MFD_ALLOW_SEALING. Otherwise, sealing is not
supported (like on all other regular files).
Compared to O_TMPFILE, it does not require a tmpfs mount-point and is not
subject to a filesystem size limit. It is still properly accounted to
memcg limits, though, and to the same overcommit or no-overcommit
accounting as all user memory.
Change-Id: Id7f5dc15f3dcca8e0e8e5d9aea4a9b53cad6a769
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If two processes share a common memory region, they usually want some
guarantees to allow safe access. This often includes:
- one side cannot overwrite data while the other reads it
- one side cannot shrink the buffer while the other accesses it
- one side cannot grow the buffer beyond previously set boundaries
If there is a trust-relationship between both parties, there is no need
for policy enforcement. However, if there's no trust relationship (eg.,
for general-purpose IPC) sharing memory-regions is highly fragile and
often not possible without local copies. Look at the following two
use-cases:
1) A graphics client wants to share its rendering-buffer with a
graphics-server. The memory-region is allocated by the client for
read/write access and a second FD is passed to the server. While
scanning out from the memory region, the server has no guarantee that
the client doesn't shrink the buffer at any time, requiring rather
cumbersome SIGBUS handling.
2) A process wants to perform an RPC on another process. To avoid huge
bandwidth consumption, zero-copy is preferred. After a message is
assembled in-memory and a FD is passed to the remote side, both sides
want to be sure that neither modifies this shared copy, anymore. The
source may have put sensible data into the message without a separate
copy and the target may want to parse the message inline, to avoid a
local copy.
While SIGBUS handling, POSIX mandatory locking and MAP_DENYWRITE provide
ways to achieve most of this, the first one is unproportionally ugly to
use in libraries and the latter two are broken/racy or even disabled due
to denial of service attacks.
This patch introduces the concept of SEALING. If you seal a file, a
specific set of operations is blocked on that file forever. Unlike locks,
seals can only be set, never removed. Hence, once you verified a specific
set of seals is set, you're guaranteed that no-one can perform the blocked
operations on this file, anymore.
An initial set of SEALS is introduced by this patch:
- SHRINK: If SEAL_SHRINK is set, the file in question cannot be reduced
in size. This affects ftruncate() and open(O_TRUNC).
- GROW: If SEAL_GROW is set, the file in question cannot be increased
in size. This affects ftruncate(), fallocate() and write().
- WRITE: If SEAL_WRITE is set, no write operations (besides resizing)
are possible. This affects fallocate(PUNCH_HOLE), mmap() and
write().
- SEAL: If SEAL_SEAL is set, no further seals can be added to a file.
This basically prevents the F_ADD_SEAL operation on a file and
can be set to prevent others from adding further seals that you
don't want.
The described use-cases can easily use these seals to provide safe use
without any trust-relationship:
1) The graphics server can verify that a passed file-descriptor has
SEAL_SHRINK set. This allows safe scanout, while the client is
allowed to increase buffer size for window-resizing on-the-fly.
Concurrent writes are explicitly allowed.
2) For general-purpose IPC, both processes can verify that SEAL_SHRINK,
SEAL_GROW and SEAL_WRITE are set. This guarantees that neither
process can modify the data while the other side parses it.
Furthermore, it guarantees that even with writable FDs passed to the
peer, it cannot increase the size to hit memory-limits of the source
process (in case the file-storage is accounted to the source).
The new API is an extension to fcntl(), adding two new commands:
F_GET_SEALS: Return a bitset describing the seals on the file. This
can be called on any FD if the underlying file supports
sealing.
F_ADD_SEALS: Change the seals of a given file. This requires WRITE
access to the file and F_SEAL_SEAL may not already be set.
Furthermore, the underlying file must support sealing and
there may not be any existing shared mapping of that file.
Otherwise, EBADF/EPERM is returned.
The given seals are _added_ to the existing set of seals
on the file. You cannot remove seals again.
The fcntl() handler is currently specific to shmem and disabled on all
files. A file needs to explicitly support sealing for this interface to
work. A separate syscall is added in a follow-up, which creates files that
support sealing. There is no intention to support this on other
file-systems. Semantics are unclear for non-volatile files and we lack any
use-case right now. Therefore, the implementation is specific to shmem.
Change-Id: I2d6247d3287c61dbe6bafabf56554e80b414f938
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (of 6):
The i_mmap_writable field counts existing writable mappings of an
address_space. To allow drivers to prevent new writable mappings, make
this counter signed and prevent new writable mappings if it is negative.
This is modelled after i_writecount and DENYWRITE.
This will be required by the shmem-sealing infrastructure to prevent any
new writable mappings after the WRITE seal has been set. In case there
exists a writable mapping, this operation will fail with EBUSY.
Note that we rely on the fact that iff you already own a writable mapping,
you can increase the counter without using the helpers. This is the same
that we do for i_writecount.
Change-Id: Id16c5b650e451956a4f6df004483cb63197c613c
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kees Cook
Francescodario Cuzzocrea
prototype74
Kevin F. Haggerty
Linus Torvalds
Stephen Smalley
myfluxi
Masahiro Yamada
Andreas Schwab
Deepak Kumar Singh
Will Deacon
Dmitry Torokhov
Dan Pasanen
Jackeagle
Uladzislau Rezki (Sony)
Igor Redko
Rafael Aquini
Luiz Capitulino
Rik van Riel
Kirill A. Shutemov
Arne Coucheron
Eric W. Biederman
Vinayak Menon
Alessandro Astone
Al Viro
Andrzej Pietrasiewicz
ChandanaKishori Chiluveru
David Drysdale
Russell King
Will Deacon
David Herrmann