For each device, the nosy driver allocates a pcilynx structure.
A use-after-free might happen in the following scenario:
1. Open nosy device for the first time and call ioctl with command
NOSY_IOC_START, then a new client A will be malloced and added to
doubly linked list.
2. Open nosy device for the second time and call ioctl with command
NOSY_IOC_START, then a new client B will be malloced and added to
doubly linked list.
3. Call ioctl with command NOSY_IOC_START for client A, then client A
will be readded to the doubly linked list. Now the doubly linked
list is messed up.
4. Close the first nosy device and nosy_release will be called. In
nosy_release, client A will be unlinked and freed.
5. Close the second nosy device, and client A will be referenced,
resulting in UAF.
The root cause of this bug is that the element in the doubly linked list
is reentered into the list.
Fix this bug by adding a check before inserting a client. If a client
is already in the linked list, don't insert it.
The following KASAN report reveals it:
BUG: KASAN: use-after-free in nosy_release+0x1ea/0x210
Write of size 8 at addr ffff888102ad7360 by task poc
CPU: 3 PID: 337 Comm: poc Not tainted 5.12.0-rc5+ #6
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
nosy_release+0x1ea/0x210
__fput+0x1e2/0x840
task_work_run+0xe8/0x180
exit_to_user_mode_prepare+0x114/0x120
syscall_exit_to_user_mode+0x1d/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
Allocated by task 337:
nosy_open+0x154/0x4d0
misc_open+0x2ec/0x410
chrdev_open+0x20d/0x5a0
do_dentry_open+0x40f/0xe80
path_openat+0x1cf9/0x37b0
do_filp_open+0x16d/0x390
do_sys_openat2+0x11d/0x360
__x64_sys_open+0xfd/0x1a0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
Freed by task 337:
kfree+0x8f/0x210
nosy_release+0x158/0x210
__fput+0x1e2/0x840
task_work_run+0xe8/0x180
exit_to_user_mode_prepare+0x114/0x120
syscall_exit_to_user_mode+0x1d/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
The buggy address belongs to the object at ffff888102ad7300 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 96 bytes inside of 128-byte region [ffff888102ad7300, ffff888102ad7380)
[ Modified to use 'list_empty()' inside proper lock - Linus ]
Link: https://lore.kernel.org/lkml/1617433116-5930-1-git-send-email-zheyuma97@gmail.com/
Reported-and-tested-by: 马哲宇 (Zheyu Ma) <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
POull io_uring fix from Jens Axboe:
"Just fixing a silly braino in a previous patch, where we'd end up
failing to compile if CONFIG_BLOCK isn't enabled.
Not that a lot of people do that, but kernel bot spotted it and it's
probably prudent to just flush this out now before -rc6.
Sorry about that, none of my test compile configs have !CONFIG_BLOCK"
* tag 'io_uring-5.12-2021-04-03' of git://git.kernel.dk/linux-block:
io_uring: fix !CONFIG_BLOCK compilation failure
Pull gfs2 fixes from Andreas Gruenbacher:
"Two more gfs2 fixes"
* tag 'gfs2-v5.12-rc2-fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: report "already frozen/thawed" errors
gfs2: Flag a withdraw if init_threads() fails
Pull RISC-V fixes from Palmer Dabbelt:
"A handful of fixes for 5.12:
- fix a stack tracing regression related to "const register asm"
variables, which have unexpected behavior.
- ensure the value to be written by put_user() is evaluated before
enabling access to userspace memory..
- align the exception vector table correctly, so we don't rely on the
firmware's handling of unaligned accesses.
- build fix to make NUMA depend on MMU, which triggered on some
randconfigs"
* tag 'riscv-for-linus-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Make NUMA depend on MMU
riscv: remove unneeded semicolon
riscv,entry: fix misaligned base for excp_vect_table
riscv: evaluate put_user() arg before enabling user access
riscv: Drop const annotation for sp
Pull powerpc fixes from Michael Ellerman:
"Fix a bug on pseries where spurious wakeups from H_PROD would prevent
partition migration from succeeding.
Fix oopses seen in pcpu_alloc(), caused by parallel faults of the
percpu mapping causing us to corrupt the protection key used for the
mapping, and cause a fatal key fault.
Thanks to Aneesh Kumar K.V, Murilo Opsfelder Araujo, and Nathan Lynch"
* tag 'powerpc-5.12-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm/book3s64: Use the correct storage key value when calling H_PROTECT
powerpc/pseries/mobility: handle premature return from H_JOIN
powerpc/pseries/mobility: use struct for shared state
Pull Hyper-V fixes from Wei Liu:
"One fix from Lu Yunlong for a double free in hvfb_probe"
* tag 'hyperv-fixes-signed-20210402' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
video: hyperv_fb: Fix a double free in hvfb_probe
Pull driver core fix from Greg KH:
"Here is a single driver core fix for a reported problem with differed
probing. It has been in linux-next for a while with no reported
problems"
* tag 'driver-core-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
driver core: clear deferred probe reason on probe retry
Pull char/misc driver fixes from Greg KH:
"Here are a few small driver char/misc changes for 5.12-rc6.
Nothing major here, a few fixes for reported issues:
- interconnect fixes for problems found
- fbcon syzbot-found fix
- extcon fixes
- firmware stratix10 bugfix
- MAINTAINERS file update.
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
drivers: video: fbcon: fix NULL dereference in fbcon_cursor()
mei: allow map and unmap of client dma buffer only for disconnected client
MAINTAINERS: Add linux-phy list and patchwork
interconnect: Fix kerneldoc warning
firmware: stratix10-svc: reset COMMAND_RECONFIG_FLAG_PARTIAL to 0
extcon: Fix error handling in extcon_dev_register
extcon: Add stubs for extcon_register_notifier_all() functions
interconnect: core: fix error return code of icc_link_destroy()
interconnect: qcom: msm8939: remove rpm-ids from non-RPM nodes
Pull staging driver fixes from Greg KH:
"Here are two rtl8192e staging driver fixes for reported problems.
Both of these have been in linux-next for a while with no reported
issues"
* tag 'staging-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: rtl8192e: Change state information from u16 to u8
staging: rtl8192e: Fix incorrect source in memcpy()
Pull serial driver fix from Greg KH:
"Here is a single serial driver fix for 5.12-rc6. Is is a revert of a
change that showed up in 5.9 that has been reported to cause problems.
It has been in linux-next for a while with no reported issues"
* tag 'tty-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
soc: qcom-geni-se: Cleanup the code to remove proxy votes
Pull USB fixes from Greg KH:
"Here are a few small USB driver fixes for 5.12-rc6 to resolve reported
problems.
They include:
- a number of cdc-acm fixes for reported problems. It seems more
people are using this driver lately...
- dwc3 driver fixes for reported problems, and fixes for the fixes :)
- dwc2 driver fixes for reported issues.
- musb driver fix.
- new USB quirk additions.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (23 commits)
usb: dwc2: Prevent core suspend when port connection flag is 0
usb: dwc2: Fix HPRT0.PrtSusp bit setting for HiKey 960 board.
usb: musb: Fix suspend with devices connected for a64
usb: xhci-mtk: fix broken streams issue on 0.96 xHCI
usb: dwc3: gadget: Clear DEP flags after stop transfers in ep disable
usbip: vhci_hcd fix shift out-of-bounds in vhci_hub_control()
USB: quirks: ignore remote wake-up on Fibocom L850-GL LTE modem
USB: cdc-acm: do not log successful probe on later errors
USB: cdc-acm: always claim data interface
USB: cdc-acm: use negation for NULL checks
USB: cdc-acm: clean up probe error labels
USB: cdc-acm: drop redundant driver-data reset
USB: cdc-acm: drop redundant driver-data assignment
USB: cdc-acm: fix use-after-free after probe failure
USB: cdc-acm: fix double free on probe failure
USB: cdc-acm: downgrade message to debug
USB: cdc-acm: untangle a circular dependency between callback and softint
cdc-acm: fix BREAK rx code path adding necessary calls
usb: gadget: udc: amd5536udc_pci fix null-ptr-dereference
usb: dwc3: pci: Enable dis_uX_susphy_quirk for Intel Merrifield
...
Pull SCSI fix from James Bottomley:
"A single fix to iscsi for a rare race condition which can cause a
kernel panic"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: iscsi: Fix race condition between login and sync thread
kernel test robot correctly pinpoints a compilation failure if
CONFIG_BLOCK isn't set:
fs/io_uring.c: In function '__io_complete_rw':
>> fs/io_uring.c:2509:48: error: implicit declaration of function 'io_rw_should_reissue'; did you mean 'io_rw_reissue'? [-Werror=implicit-function-declaration]
2509 | if ((res == -EAGAIN || res == -EOPNOTSUPP) && io_rw_should_reissue(req)) {
| ^~~~~~~~~~~~~~~~~~~~
| io_rw_reissue
cc1: some warnings being treated as errors
Ensure that we have a stub declaration of io_rw_should_reissue() for
!CONFIG_BLOCK.
Fixes: 230d50d448 ("io_uring: move reissue into regular IO path")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block fixes from Jens Axboe:
- Remove comment that never came to fruition in 22 years of development
(Christoph)
- Remove unused request flag (Christoph)
- Fix for null_blk fake timeout handling (Damien)
- Fix for IOCB_NOWAIT being ignored for O_DIRECT on raw bdevs (Pavel)
- Error propagation fix for multiple split bios (Yufen)
* tag 'block-5.12-2021-04-02' of git://git.kernel.dk/linux-block:
block: remove the unused RQF_ALLOCED flag
block: update a few comments in uapi/linux/blkpg.h
block: don't ignore REQ_NOWAIT for direct IO
null_blk: fix command timeout completion handling
block: only update parent bi_status when bio fail
Pull io_uring fixes from Jens Axboe:
"Nothing really major in here, and finally nothing really related to
signals. A few minor fixups related to the threading changes, and some
general fixes, that's it.
There's the pending gdb-get-confused-about-arch, but that's more of a
cosmetic issue, nothing that hinder use of it. And given that other
archs will likely be affected by that oddity too, better to postpone
any changes there until 5.13 imho"
* tag 'io_uring-5.12-2021-04-02' of git://git.kernel.dk/linux-block:
io_uring: move reissue into regular IO path
io_uring: fix EIOCBQUEUED iter revert
io_uring/io-wq: protect against sprintf overflow
io_uring: don't mark S_ISBLK async work as unbounded
io_uring: drop sqd lock before handling signals for SQPOLL
io_uring: handle setup-failed ctx in kill_timeouts
io_uring: always go for cancellation spin on exec
Pull ACPI fixes from Rafael Wysocki:
"These fix an ACPI tables management issue, an issue related to the
ACPI enumeration of devices and CPU wakeup in the ACPI processor
driver.
Specifics:
- Ensure that the memory occupied by ACPI tables on x86 will always
be reserved to prevent it from being allocated for other purposes
which was possible in some cases (Rafael Wysocki).
- Fix the ACPI device enumeration code to prevent it from attempting
to evaluate the _STA control method for devices with unmet
dependencies which is likely to fail (Hans de Goede).
- Fix the handling of CPU0 wakeup in the ACPI processor driver to
prevent CPU0 online failures from occurring (Vitaly Kuznetsov)"
* tag 'acpi-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: processor: Fix CPU0 wakeup in acpi_idle_play_dead()
ACPI: scan: Fix _STA getting called on devices with unmet dependencies
ACPI: tables: x86: Reserve memory occupied by ACPI tables
Pull power management fixes from Rafael Wysocki:
"These fix a race condition and an ordering issue related to using
device links in the runtime PM framework and two kerneldoc comments in
cpufreq.
Specifics:
- Fix race condition related to the handling of supplier devices
during consumer device probe and fix the order of decrementation of
two related reference counters in the runtime PM core code handling
supplier devices (Adrian Hunter).
- Fix kerneldoc comments in cpufreq that have not been updated along
with the functions documented by them (Geert Uytterhoeven)"
* tag 'pm-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: runtime: Fix race getting/putting suppliers at probe
PM: runtime: Fix ordering in pm_runtime_get_suppliers()
cpufreq: Fix scaling_{available,boost}_frequencies_show() comments
The big top of the file comment talk about grand plans that never
happened, so remove them to not confuse the readers. Also mark the
devname and volname fields as ignored as they were never used by the
kernel.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull tracing fix from Steven Rostedt:
"Fix stack trace entry size to stop showing garbage
The macro that creates both the structure and the format displayed to
user space for the stack trace event was changed a while ago to fix
the parsing by user space tooling. But this change also modified the
structure used to store the stack trace event. It changed the caller
array field from [0] to [8].
Even though the size in the ring buffer is dynamic and can be
something other than 8 (user space knows how to handle this), the 8
extra words was not accounted for when reserving the event on the ring
buffer, and added 8 more entries, due to the calculation of
"sizeof(*entry) + nr_entries * sizeof(long)", as the sizeof(*entry)
now contains 8 entries.
The size of the caller field needs to be subtracted from the size of
the entry to create the correct allocation size"
* tag 'trace-v5.12-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix stack trace event size
It's non-obvious how retry is done for block backed files, when it happens
off the kiocb done path. It also makes it tricky to deal with the iov_iter
handling.
Just mark the req as needing a reissue, and handling it from the
submission path instead. This makes it directly obvious that we're not
re-importing the iovec from userspace past the submit point, and it means
that we can just reuse our usual -EAGAIN retry path from the read/write
handling.
At some point in the future, we'll gain the ability to always reliably
return -EAGAIN through the stack. A previous attempt on the block side
didn't pan out and got reverted, hence the need to check for this
information out-of-band right now.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If IOCB_NOWAIT is set on submission, then that needs to get propagated to
REQ_NOWAIT on the block side. Otherwise we completely lose this
information, and any issuer of IOCB_NOWAIT IO will potentially end up
blocking on eg request allocation on the storage side.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Many moons ago, support was added to the SMI handlers to log s0ix entry
and exit. Early iterations of firmware on Apollo Lake correctly returned
"unsupported" for this new command they did not recognize, but
unfortunately also contained a quirk where this command would cause them
to power down rather than resume from s0ix.
Fixes for this quirk were pushed out long ago, so all APL devices still
in the field should have updated firmware. As such, we no longer need to
have the s0ix_logging_enable be opt-in, where every new platform has to
add this to their kernel commandline parameters. Change it to be on by
default.
In theory we could remove the parameter altogether: updated versions of
Chrome OS containing a kernel with this change would also be coupled
with firmware that behaves properly with these commands. Eventually we
should probably do that. For now, convert this to an opt-out parameter
so there's an emergency valve for people who are deliberately running
old firmware, or as an escape hatch in case of unforeseen regressions.
Signed-off-by: Evan Green <evgreen@chromium.org>
Link: https://lore.kernel.org/r/20210401140430.1.Ie141e6044d9b0d5aba72cb08857fdb43660c54d3@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The shifting of the u8 integer buf[3] by 24 bits to the left will
be promoted to a 32 bit signed int and then sign-extended to a
u64. In the event that the top bit of buf[3] is set then all
then all the upper 32 bits of the u64 end up as also being set
because of the sign-extension. Fix this by casting buf[i] to
a u64 before the shift.
Fixes: a28e824fb8 ("nvmem: core: Add functions to make number reading easy")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Addresses-Coverity: ("Unintended sign extension")
Link: https://lore.kernel.org/r/20210330111241.19401-8-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sometimes the clients of nvmem just want to get a number out of
nvmem. They don't want to think about exactly how many bytes the nvmem
cell took up. They just want the number. Let's make it easy.
In general this concept is useful because nvmem space is precious and
usually the fewest bits are allocated that will hold a given value on
a given system. However, even though small numbers might be fine on
one system that doesn't mean that logically the number couldn't be
bigger. Imagine nvmem containing a max frequency for a component. On
one system perhaps that fits in 16 bits. On another system it might
fit in 32 bits. The code reading this number doesn't care--it just
wants the number.
We'll provide two functions: nvmem_cell_read_variable_le_u32() and
nvmem_cell_read_variable_le_u64().
Comparing these to the existing functions like nvmem_cell_read_u32():
* These new functions have no problems if the value was stored in
nvmem in fewer bytes. It's OK to use these function as long as the
value stored will fit in 32-bits (or 64-bits).
* These functions avoid problems that the earlier APIs had with bit
offsets. For instance, you can't use nvmem_cell_read_u32() to read a
value has nbits=32 and bit_offset=4 because the nvmem cell must be
at least 5 bytes big to hold this value. The new API accounts for
this and works fine.
* These functions make it very explicit that they assume that the
number was stored in little endian format. The old functions made
this assumption whenever bit_offset was non-zero (see
nvmem_shift_read_buffer_in_place()) but didn't whenever the
bit_offset was zero.
NOTE: it's assumed that we don't need an 8-bit or 16-bit version of
this function. The 32-bit version of the function can be used to read
8-bit or 16-bit data.
At the moment, I'm only adding the "unsigned" versions of these
functions, but if it ends up being useful someone could add a "signed"
version that did 2's complement sign extension.
At the moment, I'm only adding the "little endian" versions of these
functions. Adding the "big endian" version would require adding "big
endian" support to nvmem_shift_read_buffer_in_place().
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210330111241.19401-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
