Under certain conditions, the range to be cleared by FALLOC_FL_ZERO_RANGE
may only be buffered locally and not yet have been flushed to the server.
For example:
will write two 4KiB blocks of data, which get buffered in the pagecache,
and then fallocate() is used to clear the first 4KiB block on the server -
but we don't flush the data first, which means the EOF position on the
server is wrong, and so the FSCTL_SET_ZERO_DATA RPC fails (and xfs_io
ignores the error), but then when we try to read it, we see the old data.
Fix this by preflushing any part of the target region that above the
server's idea of the EOF position to force the server to update its EOF
position.
Note, however, that we don't want to simply expand the file by moving the
EOF before doing the FSCTL_SET_ZERO_DATA[*] because someone else might see
the zeroed region or if the RPC fails we then have to try to clean it up or
risk getting corruption.
[*] And we have to move the EOF first otherwise FSCTL_SET_ZERO_DATA won't
do what we want.
This fixes the generic/008 xfstest.
[!] Note: A better way to do this might be to split the operation into two
parts: we only do FSCTL_SET_ZERO_DATA for the part of the range below the
server's EOF and then, if that worked, invalidate the buffered pages for the
part above the range.
Fixes: 6b69040247e1 ("cifs/smb3: Fix data inconsistent when zero file range") Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
cc: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
cc: Pavel Shilovsky <pshilov@microsoft.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Symbols in the bss segment are not currently exported. This is a problem
for Rust modules that link against statics, that are resident in the kernel
image. Thus export symbols in the bss segment.
Fixes: 2f7ab1267dc9 ("Kbuild: add Rust support") Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://lore.kernel.org/r/20240815074519.2684107-2-nmi@metaspace.dk
[ Reworded slightly. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
`awk` is already required by the kernel build, and the `xargs` feature
used in current Rust detection is not present in all `xargs` (notably,
toybox based xargs, used in the Android kernel build).
Signed-off-by: Matthew Maurer <mmaurer@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20230928205045.2375899-1-mmaurer@google.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Stable-dep-of: b8673d56935c ("rust: kbuild: fix export of bss symbols") Signed-off-by: Sasha Levin <sashal@kernel.org>
If the ring (rx, tx) and/or coalescing parameters (rx-frames-irq,
tx-frames-irq) have been configured while the interface was in CAN-CC
mode, but the interface is brought up in CAN-FD mode, the ring
parameters might be too big.
[WHAT & HOW]
A denominator cannot be 0, and is checked before used.
This fixes 1 DIVIDE_BY_ZERO issue reported by Coverity.
Reviewed-by: Harry Wentland <harry.wentland@amd.com> Signed-off-by: Jerry Zuo <jerry.zuo@amd.com> Signed-off-by: Alex Hung <alex.hung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Allocating a contiguous buffer of 64K may fail if memory is sufficiently
fragmented, and may cause OOM kill of an unrelated process. However we
do not need to have contiguous memory. We also do not need to zero
out the buffer since it will be overwritten with firmware data.
Errata #i2037 in AM65x/DRA80xM Processors Silicon Revision 1.0
(SPRZ452D_July 2018_Revised December 2019 [1]) mentions when an
inbound PCIe TLP spans more than two internal AXI 128-byte bursts,
the bus may corrupt the packet payload and the corrupt data may
cause associated applications or the processor to hang.
The workaround for Errata #i2037 is to limit the maximum read
request size and maximum payload size to 128 bytes. Add workaround
for Errata #i2037 here.
The errata and workaround is applicable only to AM65x SR 1.0 and
later versions of the silicon will have this fixed.
The PAPR expects the TCE table to have no entries at the time of
unset window(i.e. remove-pe). The TCE clear right now is done
before freeing the iommu table. On pSeries, the unset window
makes those entries inaccessible to the OS and the H_PUT/GET calls
fail on them with H_CONSTRAINED.
On PowerNV, this has no side effect as the TCE clear can be done
before the DMA window removal as well.
Why:
Setting IH_RB_WPTR register to 0 will not clear the RB_OVERFLOW bit
if RB_ENABLE is not set.
How to fix:
Set WPTR_OVERFLOW_CLEAR bit after RB_ENABLE bit is set.
The RB_ENABLE bit is required to be set, together with
WPTR_OVERFLOW_ENABLE bit so that setting WPTR_OVERFLOW_CLEAR bit
would clear the RB_OVERFLOW.
Signed-off-by: Danijel Slivka <danijel.slivka@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Set the host status byte when a data completion error is encountered
otherwise the upper layer may end up using the invalid zero'ed data.
The following output was observed from scsi/sd.c prior to this fix.
After being asked about support for WPA3 for BCM43224 chipset it
was found that all it takes is setting the MFP_CAPABLE flag and
mac80211 will take care of all that is needed [1].
In several places a division by fmt->vdownsampling[p] was
missing in the sizeimage[p] calculation, causing incorrect
behavior for multiplanar formats were some planes are smaller
than the first plane.
Found by new v4l2-compliance tests.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Sasha Levin <sashal@kernel.org>
Avoid mounting filesystems where the partition would overflow the
32-bits used for block number. Also refuse to mount filesystems where
the partition length is so large we cannot safely index bits in a
block bitmap.
The lookup function iwl_mvm_rcu_fw_link_id_to_link_conf() is
normally called with input from the firmware, so it should use
IWL_FW_CHECK() instead of WARN_ON().
Now there is a issue is that code checks reports a warning: implicit
narrowing conversion from type 'unsigned int' to small type 'u8' (the
'keylen' variable). Fix it by removing the 'keylen' variable.
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The Allwinner H6 IOMMU has a bypass register, which allows to circumvent
the page tables for each possible master. The reset value for this
register is 0, which disables the bypass.
The Allwinner H616 IOMMU resets this register to 0x7f, which activates
the bypass for all masters, which is not what we want.
Always clear this register to 0, to enforce the usage of page tables,
and make this driver compatible with the H616 in this respect.
When called with a 'from' that is not 4-byte-aligned, string_memcpy_fromio()
calls the movs() macro to copy the first few bytes, so that 'from' becomes
4-byte-aligned before calling rep_movs(). This movs() macro modifies 'to', and
the subsequent line modifies 'n'.
As a result, on unaligned accesses, kmsan_unpoison_memory() uses the updated
(aligned) values of 'to' and 'n'. Hence, it does not unpoison the entire
region.
Save the original values of 'to' and 'n', and pass those to
kmsan_unpoison_memory(), so that the entire region is unpoisoned.
When (AF_UNIX, SOCK_STREAM) socket connect()s to a listening socket,
the listener's sk_peer_pid/sk_peer_cred are copied to the client in
copy_peercred().
Then, the client's sk_peer_pid and sk_peer_cred are always NULL, so
we need not call put_pid() and put_cred() there.
ELF loader uses "randomize_va_space" twice. It is sysctl and can change
at any moment, so 2 loads could see 2 different values in theory with
unpredictable consequences.
Issue exactly one load for consistent value across one exec.
When a process accept()s connection from a unix socket
(either stream or seqpacket)
it gets the socket with the label of the connecting process.
For example, if a connecting process has a label 'foo',
the accept()ed socket will also have 'in' and 'out' labels 'foo',
regardless of the label of the listener process.
This is because kernel creates unix child sockets
in the context of the connecting process.
I do not see any obvious way for the listener to abuse
alien labels coming with the new socket, but,
to be on the safe side, it's better fix new socket labels.
Currently, if the access point receives an association
request containing an Extended HE Capabilities Information
Element with an invalid MCS-NSS, it triggers a firmware
crash.
This issue arises when EHT-PHY capabilities shows support
for a bandwidth and MCS-NSS set for that particular
bandwidth is filled by zeros and due to this, driver obtains
peer_nss as 0 and sending this value to firmware causes
crash.
Address this issue by implementing a validation step for
the peer_nss value before passing it to the firmware. If
the value is greater than zero, proceed with forwarding
it to the firmware. However, if the value is invalid,
reject the association request to prevent potential
firmware crashes.
drivers/net/wireless/ath/ath12k/mac.c:1922 ath12k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_80'.
drivers/net/wireless/ath/ath12k/mac.c:1922 ath12k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_160'.
drivers/net/wireless/ath/ath12k/mac.c:1924 ath12k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_80'.
In ath12k_peer_assoc_h_he() rx_mcs_80 and rx_mcs_160 variables
remain uninitialized in the following conditions:
1. Whenever the value of mcs_80 become equal to
IEEE80211_HE_MCS_NOT_SUPPORTED then rx_mcs_80 remains uninitialized.
2. Whenever phy capability is not supported 160 channel width and
value of mcs_160 become equal to IEEE80211_HE_MCS_NOT_SUPPORTED
then rx_mcs_160 remains uninitialized.
Add a simple sanity check to HD-audio HDMI Channel Map controls.
Although the value might not be accepted for the actual connection, we
can filter out some bogus values beforehand, and that should be enough
for making kselftest happier.
Although we have already a mechanism for sanity checks of input values
for control writes, it's not applied unless the kconfig
CONFIG_SND_CTL_INPUT_VALIDATION is set due to the performance reason.
Nevertheless, it still makes sense to apply the same check for user
elements despite of its cost, as that's the only way to filter out the
invalid values; the user controls are handled solely in ALSA core
code, and there is no corresponding driver, after all.
This patch adds the same input value validation for user control
elements at its put callback. The kselftest will be happier with this
change, as the incorrect values will be bailed out now with errors.
For other normal controls, the check is applied still only when
CONFIG_SND_CTL_INPUT_VALIDATION is set.
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de> Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de Reviewed-by: Jaroslav Kysela <perex@perex.cz> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de> Link: https://lore.kernel.org/20240616073454.16512-4-tiwai@suse.de Signed-off-by: Sasha Levin <sashal@kernel.org>
If the GSC FW fails to load the GSC HW hangs permanently; the only ways
to recover it are FLR or D3cold entry, with the former only being
supported on driver unload and the latter only on DGFX, for which we
don't need to load the GSC. Therefore, if GSC fails to load there is no
need to try again because the HW is stuck in the error state and the
submission to load the FW would just hang the GSCCS.
Note that, due to wa_14015076503, on MTL the GuC escalates all GSCCS
hangs to full GT resets, which would trigger a new attempt to load the
GSC FW in the post-reset HW re-init; this issue is also fixed by not
attempting to load the GSC FW after an error.
After commit a694291a6211 ("nilfs2: separate wait function from
nilfs_segctor_write") was applied, the log writing function
nilfs_segctor_do_construct() was able to issue I/O requests continuously
even if user data blocks were split into multiple logs across segments,
but two potential flaws were introduced in its error handling.
First, if nilfs_segctor_begin_construction() fails while creating the
second or subsequent logs, the log writing function returns without
calling nilfs_segctor_abort_construction(), so the writeback flag set on
pages/folios will remain uncleared. This causes page cache operations to
hang waiting for the writeback flag. For example,
truncate_inode_pages_final(), which is called via nilfs_evict_inode() when
an inode is evicted from memory, will hang.
Second, the NILFS_I_COLLECTED flag set on normal inodes remain uncleared.
As a result, if the next log write involves checkpoint creation, that's
fine, but if a partial log write is performed that does not, inodes with
NILFS_I_COLLECTED set are erroneously removed from the "sc_dirty_files"
list, and their data and b-tree blocks may not be written to the device,
corrupting the block mapping.
Fix these issues by uniformly calling nilfs_segctor_abort_construction()
on failure of each step in the loop in nilfs_segctor_do_construct(),
having it clean up logs and segment usages according to progress, and
correcting the conditions for calling nilfs_redirty_inodes() to ensure
that the NILFS_I_COLLECTED flag is cleared.
Link: https://lkml.kernel.org/r/20240814101119.4070-1-konishi.ryusuke@gmail.com Fixes: a694291a6211 ("nilfs2: separate wait function from nilfs_segctor_write") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The superblock buffers of nilfs2 can not only be overwritten at runtime
for modifications/repairs, but they are also regularly swapped, replaced
during resizing, and even abandoned when degrading to one side due to
backing device issues. So, accessing them requires mutual exclusion using
the reader/writer semaphore "nilfs->ns_sem".
Some sysfs attribute show methods read this superblock buffer without the
necessary mutual exclusion, which can cause problems with pointer
dereferencing and memory access, so fix it.
In an error injection test of a routine for mount-time recovery, KASAN
found a use-after-free bug.
It turned out that if data recovery was performed using partial logs
created by dsync writes, but an error occurred before starting the log
writer to create a recovered checkpoint, the inodes whose data had been
recovered were left in the ns_dirty_files list of the nilfs object and
were not freed.
Fix this issue by cleaning up inodes that have read the recovery data if
the recovery routine fails midway before the log writer starts.
In sch_cake, we keep track of the count of active bulk flows per host,
when running in dst/src host fairness mode, which is used as the
round-robin weight when iterating through flows. The count of active
bulk flows is updated whenever a flow changes state.
This has a peculiar interaction with the hash collision handling: when a
hash collision occurs (after the set-associative hashing), the state of
the hash bucket is simply updated to match the new packet that collided,
and if host fairness is enabled, that also means assigning new per-host
state to the flow. For this reason, the bulk flow counters of the
host(s) assigned to the flow are decremented, before new state is
assigned (and the counters, which may not belong to the same host
anymore, are incremented again).
Back when this code was introduced, the host fairness mode was always
enabled, so the decrement was unconditional. When the configuration
flags were introduced the *increment* was made conditional, but
the *decrement* was not. Which of course can lead to a spurious
decrement (and associated wrap-around to U16_MAX).
AFAICT, when host fairness is disabled, the decrement and wrap-around
happens as soon as a hash collision occurs (which is not that common in
itself, due to the set-associative hashing). However, in most cases this
is harmless, as the value is only used when host fairness mode is
enabled. So in order to trigger an array overflow, sch_cake has to first
be configured with host fairness disabled, and while running in this
mode, a hash collision has to occur to cause the overflow. Then, the
qdisc has to be reconfigured to enable host fairness, which leads to the
array out-of-bounds because the wrapped-around value is retained and
used as an array index. It seems that syzbot managed to trigger this,
which is quite impressive in its own right.
This patch fixes the issue by introducing the same conditional check on
decrement as is used on increment.
The original bug predates the upstreaming of cake, but the commit listed
in the Fixes tag touched that code, meaning that this patch won't apply
before that.
Fixes: 712639929912 ("sch_cake: Make the dual modes fairer") Reported-by: syzbot+7fe7b81d602cc1e6b94d@syzkaller.appspotmail.com Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20240903160846.20909-1-toke@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Memory state around the buggy address: ffff88806461ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806461ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888064620000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^ ffff888064620080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888064620100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
Fixes: 7f00feaf1076 ("ila: Add generic ILA translation facility") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <tom@herbertland.com> Reviewed-by: Florian Westphal <fw@strlen.de> Link: https://patch.msgid.link/20240904144418.1162839-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we cork messages in psock->cork, the last message triggers the
flushing will result in sending a sk_msg larger than the current
message size. In this case, in tcp_bpf_send_verdict(), 'copied' becomes
negative at least in the following case:
Therefore, it could lead to the following BUG with a proper value of
'copied' (thanks to syzbot). We should not use negative 'copied' as a
return value here.
x2apic_disable() clears x2apic_state and x2apic_mode unconditionally, even
when the state is X2APIC_ON_LOCKED, which prevents the kernel to disable
it thereby creating inconsistent state.
Due to the early state check for X2APIC_ON, the code path which warns about
a locked X2APIC cannot be reached.
Test for state < X2APIC_ON instead and move the clearing of the state and
mode variables to the place which actually disables X2APIC.
[ tglx: Massaged change log. Added Fixes tag. Moved clearing so it's at the
right place for back ports ]
Fixes: a57e456a7b28 ("x86/apic: Fix fallout from x2apic cleanup") Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240813014827.895381-1-yuntao.wang@linux.dev Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two distinct CPU features related to the use of XSAVES and LBR:
whether LBR is itself supported and whether XSAVES supports LBR. The LBR
subsystem correctly checks both in intel_pmu_arch_lbr_init(), but the
XSTATE subsystem does not.
The LBR bit is only removed from xfeatures_mask_independent when LBR is not
supported by the CPU, but there is no validation of XSTATE support.
If XSAVES does not support LBR the write to IA32_XSS causes a #GP fault,
leaving the state of IA32_XSS unchanged, i.e. zero. The fault is handled
with a warning and the boot continues.
Consequently the next XRSTORS which tries to restore supervisor state fails
with #GP because the RFBM has zero for all supervisor features, which does
not match the XCOMP_BV field.
As XFEATURE_MASK_FPSTATE includes supervisor features setting up the FPU
causes a #GP, which ends up in fpu_reset_from_exception_fixup(). That fails
due to the same problem resulting in recursive #GPs until the kernel runs
out of stack space and double faults.
Prevent this by storing the supported independent features in
fpu_kernel_cfg during XSTATE initialization and use that cached value for
retrieving the independent feature bits to be written into IA32_XSS.
[ tglx: Massaged change log ]
Fixes: f0dccc9da4c0 ("x86/fpu/xstate: Support dynamic supervisor feature for LBR") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Mitchell Levy <levymitchell0@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240812-xsave-lbr-fix-v3-1-95bac1bf62f4@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
0x7d and 0x7e bytes are meant to be escaped in the data portion of
frames, but this didn't occur since next_chunk_len() had an off-by-one
error. That also resulted in the final byte of a payload being written
as a separate tty write op.
The chunk prior to an escaped byte would be one byte short, and the
next call would never test the txpos+1 case, which is where the escaped
byte was located. That meant it never hit the escaping case in
mctp_serial_tx_work().
Example Input: 01 00 08 c8 7e 80 02
Previous incorrect chunks from next_chunk_len():
01 00 08
c8 7e 80
02
With this fix:
01 00 08 c8
7e
80 02
Cc: stable@vger.kernel.org Fixes: a0c2ccd9b5ad ("mctp: Add MCTP-over-serial transport binding") Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We found a null pointer accessing in tracefs[1], the reason is that the
variable 'ei_child' is set to LIST_POISON1, that means the list was
removed in eventfs_remove_rec. so when access the ei_child->is_freed, the
panic triggered.
by the way, the following script can reproduce this panic
loop1 (){
while true
do
echo "p:kp submit_bio" > /sys/kernel/debug/tracing/kprobe_events
echo "" > /sys/kernel/debug/tracing/kprobe_events
done
}
loop2 (){
while true
do
tree /sys/kernel/debug/tracing/events/kprobes/
done
}
loop1 &
loop2
The issue is that list_del() is used on an SRCU protected list variable
before the synchronization occurs. This can poison the list pointers while
there is a reader iterating the list.
This is simply fixed by using list_del_rcu() that is specifically made for
this purpose.
The fscache_cookie_lru_timer is initialized when the fscache module
is inserted, but is not deleted when the fscache module is removed.
If timer_reduce() is called before removing the fscache module,
the fscache_cookie_lru_timer will be added to the timer list of
the current cpu. Afterwards, a use-after-free will be triggered
in the softIRQ after removing the fscache module, as follows:
Patch series "userfaultfd: fix races around pmd_trans_huge() check", v2.
The pmd_trans_huge() code in mfill_atomic() is wrong in three different
ways depending on kernel version:
1. The pmd_trans_huge() check is racy and can lead to a BUG_ON() (if you hit
the right two race windows) - I've tested this in a kernel build with
some extra mdelay() calls. See the commit message for a description
of the race scenario.
On older kernels (before 6.5), I think the same bug can even
theoretically lead to accessing transhuge page contents as a page table
if you hit the right 5 narrow race windows (I haven't tested this case).
2. As pointed out by Qi Zheng, pmd_trans_huge() is not sufficient for
detecting PMDs that don't point to page tables.
On older kernels (before 6.5), you'd just have to win a single fairly
wide race to hit this.
I've tested this on 6.1 stable by racing migration (with a mdelay()
patched into try_to_migrate()) against UFFDIO_ZEROPAGE - on my x86
VM, that causes a kernel oops in ptlock_ptr().
3. On newer kernels (>=6.5), for shmem mappings, khugepaged is allowed
to yank page tables out from under us (though I haven't tested that),
so I think the BUG_ON() checks in mfill_atomic() are just wrong.
I decided to write two separate fixes for these (one fix for bugs 1+2, one
fix for bug 3), so that the first fix can be backported to kernels
affected by bugs 1+2.
This patch (of 2):
This fixes two issues.
I discovered that the following race can occur:
mfill_atomic other thread
============ ============
<zap PMD>
pmdp_get_lockless() [reads none pmd]
<bail if trans_huge>
<if none:>
<pagefault creates transhuge zeropage>
__pte_alloc [no-op]
<zap PMD>
<bail if pmd_trans_huge(*dst_pmd)>
BUG_ON(pmd_none(*dst_pmd))
I have experimentally verified this in a kernel with extra mdelay() calls;
the BUG_ON(pmd_none(*dst_pmd)) triggers.
On kernels newer than commit 0d940a9b270b ("mm/pgtable: allow
pte_offset_map[_lock]() to fail"), this can't lead to anything worse than
a BUG_ON(), since the page table access helpers are actually designed to
deal with page tables concurrently disappearing; but on older kernels
(<=6.4), I think we could probably theoretically race past the two
BUG_ON() checks and end up treating a hugepage as a page table.
The second issue is that, as Qi Zheng pointed out, there are other types
of huge PMDs that pmd_trans_huge() can't catch: devmap PMDs and swap PMDs
(in particular, migration PMDs).
On <=6.4, this is worse than the first issue: If mfill_atomic() runs on a
PMD that contains a migration entry (which just requires winning a single,
fairly wide race), it will pass the PMD to pte_offset_map_lock(), which
assumes that the PMD points to a page table.
Breakage follows: First, the kernel tries to take the PTE lock (which will
crash or maybe worse if there is no "struct page" for the address bits in
the migration entry PMD - I think at least on X86 there usually is no
corresponding "struct page" thanks to the PTE inversion mitigation, amd64
looks different).
If that didn't crash, the kernel would next try to write a PTE into what
it wrongly thinks is a page table.
As part of fixing these issues, get rid of the check for pmd_trans_huge()
before __pte_alloc() - that's redundant, we're going to have to check for
that after the __pte_alloc() anyway.
Backport note: pmdp_get_lockless() is pmd_read_atomic() in older kernels.
Since khugepaged was changed to allow retracting page tables in file
mappings without holding the mmap lock, these BUG_ON()s are wrong - get
rid of them.
We could also remove the preceding "if (unlikely(...))" block, but then we
could reach pte_offset_map_lock() with transhuge pages not just for file
mappings but also for anonymous mappings - which would probably be fine
but I think is not necessarily expected.
Link: https://lkml.kernel.org/r/20240813-uffd-thp-flip-fix-v2-2-5efa61078a41@google.com Fixes: 1d65b771bc08 ("mm/khugepaged: retract_page_tables() without mmap or vma lock") Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Pavel Emelyanov <xemul@virtuozzo.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The timerlat interface will get and put the task that is part of the
"kthread" field of the osn_var to keep it around until all references are
released. But here's a race in the "stop_kthread()" code that will call
put_task_struct() on the kthread if it is not a kernel thread. This can
race with the releasing of the references to that task struct and the
put_task_struct() can be called twice when it should have been called just
once.
Take the interface_lock() in stop_kthread() to synchronize this change.
But to do so, the function stop_per_cpu_kthreads() needs to change the
loop from for_each_online_cpu() to for_each_possible_cpu() and remove the
cpu_read_lock(), as the interface_lock can not be taken while the cpu
locks are held. The only side effect of this change is that it may do some
extra work, as the per_cpu variables of the offline CPUs would not be set
anyway, and would simply be skipped in the loop.
In __tracing_open(), when max latency tracers took place on the cpu,
the time start of its buffer would be updated, then event entries with
timestamps being earlier than start of the buffer would be skipped
(see tracing_iter_reset()).
Softlockup will occur if the kernel is non-preemptible and too many
entries were skipped in the loop that reset every cpu buffer, so add
cond_resched() to avoid it.
Cc: stable@vger.kernel.org Fixes: 2f26ebd549b9a ("tracing: use timestamp to determine start of latency traces") Link: https://lore.kernel.org/20240827124654.3817443-1-zhengyejian@huaweicloud.com Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Zheng Yejian <zhengyejian@huaweicloud.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The timerlat tracer can use user space threads to check for osnoise and
timer latency. If the program using this is killed via a SIGTERM, the
threads are shutdown one at a time and another tracing instance can start
up resetting the threads before they are fully closed. That causes the
hrtimer assigned to the kthread to be shutdown and freed twice when the
dying thread finally closes the file descriptors, causing a use-after-free
bug.
Only cancel the hrtimer if the associated thread is still around. Also add
the interface_lock around the resetting of the tlat_var->kthread.
Note, this is just a quick fix that can be backported to stable. A real
fix is to have a better synchronization between the shutdown of old
threads and the starting of new ones.
The start_kthread() and stop_thread() code was not always called with the
interface_lock held. This means that the kthread variable could be
unexpectedly changed causing the kthread_stop() to be called on it when it
should not have been, leading to:
while true; do
rtla timerlat top -u -q & PID=$!;
sleep 5;
kill -INT $PID;
sleep 0.001;
kill -TERM $PID;
wait $PID;
done
This is because it would mistakenly call kthread_stop() on a user space
thread making it "exit" before it actually exits.
Since kthreads are created based on global behavior, use a cpumask to know
when kthreads are running and that they need to be shutdown before
proceeding to do new work.
Commit e882575efc77 ("spi: rockchip: Suspend and resume the bus during
NOIRQ_SYSTEM_SLEEP_PM ops") stopped respecting runtime PM status and
simply disabled clocks unconditionally when suspending the system. This
causes problems when the device is already runtime suspended when we go
to sleep -- in which case we double-disable clocks and produce a
WARNing.
Switch back to pm_runtime_force_{suspend,resume}(), because that still
seems like the right thing to do, and the aforementioned commit makes no
explanation why it stopped using it.
Also, refactor some of the resume() error handling, because it's not
actually a good idea to re-disable clocks on failure.
Fixes: e882575efc77 ("spi: rockchip: Suspend and resume the bus during NOIRQ_SYSTEM_SLEEP_PM ops") Cc: stable@vger.kernel.org Reported-by: Ondřej Jirman <megi@xff.cz> Closes: https://lore.kernel.org/lkml/20220621154218.sau54jeij4bunf56@core/ Signed-off-by: Brian Norris <briannorris@chromium.org> Link: https://patch.msgid.link/20240827171126.1115748-1-briannorris@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 8c61291fd850 ("mm: fix incorrect vbq reference in
purge_fragmented_block") extended the 'vmap_block' structure to contain a
'cpu' field which is set at allocation time to the id of the initialising
CPU.
When a new 'vmap_block' is being instantiated by new_vmap_block(), the
partially initialised structure is added to the local 'vmap_block_queue'
xarray before the 'cpu' field has been initialised. If another CPU is
concurrently walking the xarray (e.g. via vm_unmap_aliases()), then it
may perform an out-of-bounds access to the remote queue thanks to an
uninitialised index.
This has been observed as UBSAN errors in Android:
Fix the condition to exclude the elfcorehdr segment from the SHA digest
calculation.
The j iterator is an index into the output sha_regions[] array, not into
the input image->segment[] array. Once it reaches
image->elfcorehdr_index, all subsequent segments are excluded. Besides,
if the purgatory segment precedes the elfcorehdr segment, the elfcorehdr
may be wrongly included in the calculation.
Link: https://lkml.kernel.org/r/20240805150750.170739-1-petr.tesarik@suse.com Fixes: f7cc804a9fd4 ("kexec: exclude elfcorehdr from the segment digest") Signed-off-by: Petr Tesarik <ptesarik@suse.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Sourabh Jain <sourabhjain@linux.ibm.com> Cc: Eric DeVolder <eric_devolder@yahoo.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The mcp251x_hw_wake() function is called with the mpc_lock mutex held and
disables the interrupt handler so that no interrupts can be processed while
waking the device. If an interrupt has already occurred then waiting for
the interrupt handler to complete will deadlock because it will be trying
to acquire the same mutex.
Correct the pll postdiv shift used in clk_trion_pll_postdiv_set_rate
API. The shift value is not same for different types of plls and
should be taken from the pll's .post_div_shift member.
Add notifier function for PLL0 clock. In the function, the cpu_root clock
should be operated by saving its current parent and setting a new safe
parent (osc clock) before setting the PLL0 clock rate. After setting PLL0
rate, it should be switched back to the original parent clock.
Fixes: e2c510d6d630 ("riscv: dts: starfive: Add cpu scaling for JH7110 SoC") Cc: stable@vger.kernel.org Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com> Link: https://lore.kernel.org/r/20240826080430.179788-2-xingyu.wu@starfivetech.com Reviewed-by: Hal Feng <hal.feng@starfivetech.com> Tested-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The existing code uses min_t(ssize_t, outarg.size, XATTR_LIST_MAX) when
parsing the FUSE daemon's response to a zero-length getxattr/listxattr
request.
On 32-bit kernels, where ssize_t and outarg.size are the same size, this is
wrong: The min_t() will pass through any size values that are negative when
interpreted as signed.
fuse_listxattr() will then return this userspace-supplied negative value,
which callers will treat as an error value.
This kind of bug pattern can lead to fairly bad security bugs because of
how error codes are used in the Linux kernel. If a caller were to convert
the numeric error into an error pointer, like so:
struct foo *func(...) {
int len = fuse_getxattr(..., NULL, 0);
if (len < 0)
return ERR_PTR(len);
...
}
then it would end up returning this userspace-supplied negative value cast
to a pointer - but the caller of this function wouldn't recognize it as an
error pointer (IS_ERR_VALUE() only detects values in the narrow range in
which legitimate errno values are), and so it would just be treated as a
kernel pointer.
I think there is at least one theoretical codepath where this could happen,
but that path would involve virtio-fs with submounts plus some weird
SELinux configuration, so I think it's probably not a concern in practice.
In the case where the aux writeback list is dropped (e.g. the pages
have been truncated or the connection is broken), the stats for
its pages and backing device info need to be updated as well.
Commit 616f87661792 ("mmc: pass queue_limits to blk_mq_alloc_disk") [1]
revealed the long living issue in dw_mmc.c driver, existing since the
time when it was first introduced in commit f95f3850f7a9 ("mmc: dw_mmc:
Add Synopsys DesignWare mmc host driver."), also making kernel boot
broken on platforms using dw_mmc driver with 16K or 64K pages enabled,
with this message in dmesg:
mmcblk: probe of mmc0:0001 failed with error -22
That's happening because mmc_blk_probe() fails when it calls
blk_validate_limits() consequently, which returns the error due to
failed max_segment_size check in this code:
/*
* The maximum segment size has an odd historic 64k default that
* drivers probably should override. Just like the I/O size we
* require drivers to at least handle a full page per segment.
*/
...
if (WARN_ON_ONCE(lim->max_segment_size < PAGE_SIZE))
return -EINVAL;
In case when IDMAC (Internal DMA Controller) is used, dw_mmc.c always
sets .max_seg_size to 4 KiB:
mmc->max_seg_size = 0x1000;
The comment in the code above explains why it's incorrect. Arnd
suggested setting .max_seg_size to .max_req_size to fix it, which is
also what some other drivers are doing:
This change is not only fixing the boot with 16K/64K pages, but also
leads to a better MMC performance. The linear write performance was
tested on E850-96 board (eMMC only), before commit [1] (where it's
possible to boot with 16K/64K pages without this fix, to be able to do
a comparison). It was tested with this command:
Unfortunately, SD card controller is not enabled in E850-96 yet, so it
wasn't possible for me to run the test on some cheap SD cards to check
this patch's impact on those. But it's possible that this change might
also reduce the writes count, thus improving SD/eMMC longevity.
All credit for the analysis and the suggested solution goes to Arnd.
Applying MMC_QUIRK_BROKEN_SD_CACHE is broken, as the card's SD quirks are
referenced in sd_parse_ext_reg_perf() prior to the quirks being initialized
in mmc_blk_probe().
To fix this problem, let's split out an SD-specific list of quirks and
apply in mmc_sd_init_card() instead. In this way, sd_read_ext_regs() to has
the available information for not assigning the SD_EXT_PERF_CACHE as one of
the (un)supported features, which in turn allows mmc_sd_init_card() to
properly skip execution of sd_enable_cache().
Fixes: c467c8f08185 ("mmc: Add MMC_QUIRK_BROKEN_SD_CACHE for Kingston Canvas Go Plus from 11/2019") Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com> Co-developed-by: Keita Aihara <keita.aihara@sony.com> Signed-off-by: Keita Aihara <keita.aihara@sony.com> Reviewed-by: Dragan Simic <dsimic@manjaro.org> Reviewed-by: Avri Altman <avri.altman@wdc.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240820230631.GA436523@sony.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Due to 59b047bc98084f8af2c41483e4d68a5adf2fa7f7 there could be keys stored
with the wrong address type so this attempt to detect it and ignore them
instead of just failing to load all keys.
Cc: stable@vger.kernel.org Link: https://github.com/bluez/bluez/issues/875 Fixes: 59b047bc9808 ("Bluetooth: MGMT/SMP: Fix address type when using SMP over BREDR/LE") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org Link: https://github.com/bluez/bluez/issues/875 Fixes: 59b047bc9808 ("Bluetooth: MGMT/SMP: Fix address type when using SMP over BREDR/LE") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently while defining `THIS_MODULE` symbol in `module!()`, the
pointer used to construct `ThisModule` is derived from an immutable
reference of `__this_module`, which means the pointer doesn't have
the provenance for writing, and that means any write to that pointer
is UB regardless of data races or not. However, the usage of
`THIS_MODULE` includes passing this pointer to functions that may write
to it (probably in unsafe code), and this will create soundness issues.
One way to fix this is using `addr_of_mut!()` but that requires the
unstable feature "const_mut_refs". So instead of `addr_of_mut()!`,
an extern static `Opaque` is used here: since `Opaque<T>` is transparent
to `T`, an extern static `Opaque` will just wrap the C symbol (defined
in a C compile unit) in an `Opaque`, which provides a pointer with
writable provenance via `Opaque::get()`. This fix the potential UBs
because of pointer provenance unmatched.
Reported-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Trevor Gross <tmgross@umich.edu> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Gary Guo <gary@garyguo.net> Closes: https://rust-for-linux.zulipchat.com/#narrow/stream/x/topic/x/near/465412664 Fixes: 1fbde52bde73 ("rust: add `macros` crate") Cc: stable@vger.kernel.org # 6.6.x: be2ca1e03965: ("rust: types: Make Opaque::get const") Link: https://lore.kernel.org/r/20240828180129.4046355-1-boqun.feng@gmail.com
[ Fixed two typos, reworded title. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rt_mutex_handle_deadlock() is called with rt_mutex::wait_lock held. In the
good case it returns with the lock held and in the deadlock case it emits a
warning and goes into an endless scheduling loop with the lock held, which
triggers the 'scheduling in atomic' warning.
Unlock rt_mutex::wait_lock in the dead lock case before issuing the warning
and dropping into the schedule for ever loop.
[ tglx: Moved unlock before the WARN(), removed the pointless comment,
massaged changelog, added Fixes tag ]
iounmap() on x86 occasionally fails to unmap because the provided valid
ioremap address is not below high_memory. It turned out that this
happens due to KASLR.
KASLR uses the full address space between PAGE_OFFSET and vaddr_end to
randomize the starting points of the direct map, vmalloc and vmemmap
regions. It thereby limits the size of the direct map by using the
installed memory size plus an extra configurable margin for hot-plug
memory. This limitation is done to gain more randomization space
because otherwise only the holes between the direct map, vmalloc,
vmemmap and vaddr_end would be usable for randomizing.
The limited direct map size is not exposed to the rest of the kernel, so
the memory hot-plug and resource management related code paths still
operate under the assumption that the available address space can be
determined with MAX_PHYSMEM_BITS.
request_free_mem_region() allocates from (1 << MAX_PHYSMEM_BITS) - 1
downwards. That means the first allocation happens past the end of the
direct map and if unlucky this address is in the vmalloc space, which
causes high_memory to become greater than VMALLOC_START and consequently
causes iounmap() to fail for valid ioremap addresses.
MAX_PHYSMEM_BITS cannot be changed for that because the randomization
does not align with address bit boundaries and there are other places
which actually require to know the maximum number of address bits. All
remaining usage sites of MAX_PHYSMEM_BITS have been analyzed and found
to be correct.
Cure this by exposing the end of the direct map via PHYSMEM_END and use
that for the memory hot-plug and resource management related places
instead of relying on MAX_PHYSMEM_BITS. In the KASLR case PHYSMEM_END
maps to a variable which is initialized by the KASLR initialization and
otherwise it is based on MAX_PHYSMEM_BITS as before.
To prevent future hickups add a check into add_pages() to catch callers
trying to add memory above PHYSMEM_END.
Fixes: 0483e1fa6e09 ("x86/mm: Implement ASLR for kernel memory regions") Reported-by: Max Ramanouski <max8rr8@gmail.com> Reported-by: Alistair Popple <apopple@nvidia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-By: Max Ramanouski <max8rr8@gmail.com> Tested-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Kees Cook <kees@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/87ed6soy3z.ffs@tglx Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gicv2m_of_init() fails to perform an of_node_put() when
of_address_to_resource() fails, leading to a refcount leak.
Address this by moving the error handling path outside of the loop and
making it common to all failure modes.
Fixes: 4266ab1a8ff5 ("irqchip/gic-v2m: Refactor to prepare for ACPI support") Signed-off-by: Ma Ke <make24@iscas.ac.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240820092843.1219933-1-make24@iscas.ac.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Thanks to Thomas Gleixner's analysis, the issue is caused by the low
initial period (1) of the frequency estimation algorithm, which triggers
the defects of the HW, specifically erratum HSW11 and HSW143. (For the
details, please refer https://lore.kernel.org/lkml/87plq9l5d2.ffs@tglx/)
The HSW11 requires a period larger than 100 for the INST_RETIRED.ALL
event, but the initial period in the freq mode is 1. The erratum is the
same as the BDM11, which has been supported in the kernel. A minimum
period of 128 is enforced as well on HSW.
HSW143 is regarding that the fixed counter 1 may overcount 32 with the
Hyper-Threading is enabled. However, based on the test, the hardware
has more issues than it tells. Besides the fixed counter 1, the message
'interrupt took too long' can be observed on any counter which was armed
with a period < 32 and two events expired in the same NMI. A minimum
period of 32 is enforced for the rest of the events.
The recommended workaround code of the HSW143 is not implemented.
Because it only addresses the issue for the fixed counter. It brings
extra overhead through extra MSR writing. No related overcounting issue
has been reported so far.
Fixes: 3a632cb229bf ("perf/x86/intel: Add simple Haswell PMU support") Reported-by: Li Huafei <lihuafei1@huawei.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240819183004.3132920-1-kan.liang@linux.intel.com Closes: https://lore.kernel.org/lkml/20240729223328.327835-1-lihuafei1@huawei.com/ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In ata_host_alloc(), if devres_alloc() fails to allocate the device host
resource data pointer, the already allocated ata_host structure is not
freed before returning from the function. This results in a potential
memory leak.
Call kfree(host) before jumping to the error handling path to ensure
that the ata_host structure is properly freed if devres_alloc() fails.
Fixes: 2623c7a5f279 ("libata: add refcounting to ata_host") Cc: stable@vger.kernel.org Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unlock before returning an error code if this allocation fails.
Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers") Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Steve French reported null pointer dereference error from sha256 lib.
cifs.ko can send session setup requests on reused connection.
If reused connection is used for binding session, conn->binding can
still remain true and generate_preauth_hash() will not set
sess->Preauth_HashValue and it will be NULL.
It is used as a material to create an encryption key in
ksmbd_gen_smb311_encryptionkey. ->Preauth_HashValue cause null pointer
dereference error from crypto_shash_update().
If smb2_compound_op() is called with a valid @cfile and returned
-EINVAL, we need to call cifs_get_writable_path() before retrying it
as the reference of @cfile was already dropped by previous call.
This fixes the following KASAN splat when running fstests generic/013
against Windows Server 2022:
CIFS: Attempting to mount //w22-fs0/scratch
run fstests generic/013 at 2024-09-02 19:48:59
==================================================================
BUG: KASAN: slab-use-after-free in detach_if_pending+0xab/0x200
Write of size 8 at addr ffff88811f1a3730 by task kworker/3:2/176
If an interrupt occurs in queued_spin_lock_slowpath() after we increment
qnodesp->count and before node->lock is initialized, another CPU might
see stale lock values in get_tail_qnode(). If the stale lock value happens
to match the lock on that CPU, then we write to the "next" pointer of
the wrong qnode. This causes a deadlock as the former CPU, once it becomes
the head of the MCS queue, will spin indefinitely until it's "next" pointer
is set by its successor in the queue.
Running stress-ng on a 16 core (16EC/16VP) shared LPAR, results in
occasional lockups similar to the following:
The following code flow illustrates how the deadlock occurs.
For the sake of brevity, assume that both locks (A and B) are
contended and we call the queued_spin_lock_slowpath() function.
Lenovo V145 is having phase inverted dmic but simply applying inverted
dmic fixups does not work. Chaining up verb fixes for ALC283 enables
inverting dmic fixup to work properly.
The Sirius notebooks have two sets of speakers 0x17 (sides) and
0x1d (top center). The side speakers are active by default but
the top speakers aren't.
This patch provides a pincfg quirk to activate the top speakers.
If host supports Bus Lock Detect, KVM advertises it to guests even if
SVM support is absent. Additionally, guest wouldn't be able to use it
despite guest CPUID bit being set. Fix it by unconditionally clearing
the feature bit in KVM cpu capability.
Reported-by: Jim Mattson <jmattson@google.com> Closes: https://lore.kernel.org/r/CALMp9eRet6+v8Y1Q-i6mqPm4hUow_kJNhmVHfOV8tMfuSS=tVg@mail.gmail.com Fixes: 76ea438b4afc ("KVM: X86: Expose bus lock debug exception to guest") Cc: stable@vger.kernel.org Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20240808062937.1149-4-ravi.bangoria@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If these msrs are read by the emulator (e.g due to 'force emulation' prefix),
SVM code currently fails to extract the corresponding segment bases,
and return them to the emulator.
Grab kvm->srcu when processing KVM_SET_VCPU_EVENTS, as KVM will forcibly
leave nested VMX/SVM if SMM mode is being toggled, and leaving nested VMX
reads guest memory.
Note, kvm_vcpu_ioctl_x86_set_vcpu_events() can also be called from KVM_RUN
via sync_regs(), which already holds SRCU. I.e. trying to precisely use
kvm_vcpu_srcu_read_lock() around the problematic SMM code would cause
problems. Acquiring SRCU isn't all that expensive, so for simplicity,
grab it unconditionally for KVM_SET_VCPU_EVENTS.
kernel detects that snd_pcm_suspend_all() access a freed
'snd_soc_pcm_runtime' object when the system is suspended, which
leads to a use-after-free bug:
[ 52.047746] BUG: KASAN: use-after-free in snd_pcm_suspend_all+0x1a8/0x270
[ 52.047765] Read of size 1 at addr ffff0000b9434d50 by task systemd-sleep/2330
The snd_pcm_sync_stop() has a NULL check on 'substream->runtime' before
making any access. So we need to always set 'substream->runtime' to NULL
everytime we kfree() it.
This is a clear use-after-free error. We remove it, and rely on checking
the return code of vcap_del_rule.
Reported-by: Dan Carpenter <error27@gmail.com> Closes: https://lore.kernel.org/kernel-janitors/7bffefc6-219a-4f71-baa0-ad4526e5c198@kili.mountain/ Fixes: c956b9b318d9 ("net: microchip: sparx5: Adding KUNIT tests of key/action values in VCAP API") Signed-off-by: Jens Emil Schulz Østergaard <jensemil.schulzostergaard@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If netem_dequeue() enqueues packet to inner qdisc and that qdisc
returns __NET_XMIT_STOLEN. The packet is dropped but
qdisc_tree_reduce_backlog() is not called to update the parent's
q.qlen, leading to the similar use-after-free as Commit e04991a48dbaf382 ("netem: fix return value if duplicate enqueue
fails")
Commands to trigger KASAN UaF:
ip link add type dummy
ip link set lo up
ip link set dummy0 up
tc qdisc add dev lo parent root handle 1: drr
tc filter add dev lo parent 1: basic classid 1:1
tc class add dev lo classid 1:1 drr
tc qdisc add dev lo parent 1:1 handle 2: netem
tc qdisc add dev lo parent 2: handle 3: drr
tc filter add dev lo parent 3: basic classid 3:1 action mirred egress
redirect dev dummy0
tc class add dev lo classid 3:1 drr
ping -c1 -W0.01 localhost # Trigger bug
tc class del dev lo classid 1:1
tc class add dev lo classid 1:1 drr
ping -c1 -W0.01 localhost # UaF