When sending packets between nodes in netns, it calls tipc_lxc_xmit() for
peer node to receive the packets where tipc_sk_mcast_rcv()/tipc_sk_rcv()
might be called, and it's pretty much like in tipc_rcv().
Currently the local 'node rw lock' is held during calling tipc_lxc_xmit()
to protect the peer_net not being freed by another thread. However, when
receiving these packets, tipc_node_add_conn() might be called where the
peer 'node rw lock' is acquired. Then a dead lock warning is triggered by
lockdep detector, although it is not a real dead lock:
WARNING: possible recursive locking detected
--------------------------------------------
conn_server/1086 is trying to acquire lock: ffff8880065cb020 (&n->lock#2){++--}-{2:2}, \
at: tipc_node_add_conn.cold.76+0xaa/0x211 [tipc]
but task is already holding lock: ffff8880065cd020 (&n->lock#2){++--}-{2:2}, \
at: tipc_node_xmit+0x285/0xb30 [tipc]
other info that might help us debug this:
Possible unsafe locking scenario:
This patch avoids this warning by not holding the 'node rw lock' before
calling tipc_lxc_xmit(). As to protect the 'peer_net', rcu_read_lock()
should be enough, as in cleanup_net() when freeing the netns, it calls
synchronize_rcu() before the free is continued.
Also since tipc_lxc_xmit() is like the RX path in tipc_rcv(), it makes
sense to call it under rcu_read_lock(). Note that the right lock order
must be:
After commit 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job
before return error"), any procedure after ocfs2_dlm_init() fails will
trigger crash when calling ocfs2_dlm_shutdown().
ie: On local mount mode, no dlm resource is initialized. If
ocfs2_mount_volume() fails in ocfs2_find_slot(), error handling will call
ocfs2_dlm_shutdown(), then does dlm resource cleanup job, which will
trigger kernel crash.
This solution should bypass uninitialized resources in
ocfs2_dlm_shutdown().
Link: https://lkml.kernel.org/r/20220815085754.20417-1-heming.zhao@suse.com Fixes: 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job before return error") Signed-off-by: Heming Zhao <heming.zhao@suse.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the commit f73b12812a3d
("tipc: improve throughput between nodes in netns"), we're missing a check
to handle TIPC_DIRECT_MSG type, it's still using old sending mechanism for
this message type. So, throughput improvement is not significant as
expected.
Besides that, when sending a large message with that type, we're also
handle wrong receiving queue, it should be enqueued in socket receiving
instead of multicast messages.
Fix this by adding the missing case for TIPC_DIRECT_MSG.
Fixes: f73b12812a3d ("tipc: improve throughput between nodes in netns") Reported-by: Tuong Lien <tuong.t.lien@dektech.com.au> Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au> Acked-by: Jon Maloy <jmaloy@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is possible to get an instant RX timeout or end-of-transfer interrupt
before RX DMA was started, if transaction is less than 16 bytes. Transfer
should be handled in PIO mode in this case because DMA can't handle it.
This patch brings back the original behaviour of the driver that was
changed by accident by a previous commit, it fixes occasional Bluetooth HW
initialization failures which I started to notice recently.
In the function 'tipc_disc_rcv()', the 'msg_peer_net_hash()' is called
to read the header data field but after the message skb has been freed,
that might result in a garbage value...
This commit fixes it by defining a new local variable to store the data
first, just like the other header fields' handling.
Fixes: f73b12812a3d ("tipc: improve throughput between nodes in netns") Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch results in some qemu test failures, specifically xilinx-zynq-a9
machine and zynq-zc702 as well as zynq-zed devicetree files, when trying
to boot from USB drive.
If CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, memblock_free_pages()
only releases pages to the buddy allocator if they are not in the
deferred range. This is correct for free pages (as defined by
for_each_free_mem_pfn_range_in_zone()) because free pages in the
deferred range will be initialized and released as part of the deferred
init process. memblock_free_pages() is called by memblock_free_late(),
which is used to free reserved ranges after memblock_free_all() has
run. All pages in reserved ranges have been initialized at that point,
and accordingly, those pages are not touched by the deferred init
process. This means that currently, if the pages that
memblock_free_late() intends to release are in the deferred range, they
will never be released to the buddy allocator. They will forever be
reserved.
In addition, memblock_free_pages() calls kmsan_memblock_free_pages(),
which is also correct for free pages but is not correct for reserved
pages. KMSAN metadata for reserved pages is initialized by
kmsan_init_shadow(), which runs shortly before memblock_free_all().
For both of these reasons, memblock_free_pages() should only be called
for free pages, and memblock_free_late() should call __free_pages_core()
directly instead.
One case where this issue can occur in the wild is EFI boot on
x86_64. The x86 EFI code reserves all EFI boot services memory ranges
via memblock_reserve() and frees them later via memblock_free_late()
(efi_reserve_boot_services() and efi_free_boot_services(),
respectively). If any of those ranges happens to fall within the
deferred init range, the pages will not be released and that memory will
be unavailable.
For example, on an Amazon EC2 t3.micro VM (1 GB) booting via EFI:
The inline assembly for arm64's cmpxchg_double*() implementations use a
+Q constraint to hazard against other accesses to the memory location
being exchanged. However, the pointer passed to the constraint is a
pointer to unsigned long, and thus the hazard only applies to the first
8 bytes of the location.
GCC can take advantage of this, assuming that other portions of the
location are unchanged, leading to a number of potential problems.
This is similar to what we fixed back in commit:
fee960bed5e857eb ("arm64: xchg: hazard against entire exchange variable")
... but we forgot to adjust cmpxchg_double*() similarly at the same
time.
The same problem applies, as demonstrated with the following test:
Notice that at the lines with "BANG" comments, GCC has assumed that the
higher 8 bytes are unchanged by the cmpxchg_double() call, and that
`hi_old ^ hi_new` can be reduced to a constant zero, for both LSE and
LL/SC versions of cmpxchg_double().
This patch fixes the issue by passing a pointer to __uint128_t into the
+Q constraint, ensuring that the compiler hazards against the entire 16
bytes being modified.
With this change, GCC 12.1.0 compiles the above test as:
... sampling the high 8 bytes before and after the cmpxchg, and
performing an EOR, as we'd expect.
For backporting, I've tested this atop linux-4.9.y with GCC 5.5.0. Note
that linux-4.9.y is oldest currently supported stable release, and
mandates GCC 5.1+. Unfortunately I couldn't get a GCC 5.1 binary to run
on my machines due to library incompatibilities.
I've also used a standalone test to check that we can use a __uint128_t
pointer in a +Q constraint at least as far back as GCC 4.8.5 and LLVM
3.9.1.
When CONFIG_ARM64_LSE_ATOMICS=y, each use of an LL/SC atomic results in
a fragment of code being generated in a subsection without a clear
association with its caller. A trampoline in the caller branches to the
LL/SC atomic with with a direct branch, and the atomic directly branches
back into its trampoline.
This breaks backtracing, as any PC within the out-of-line fragment will
be symbolized as an offset from the nearest prior symbol (which may not
be the function using the atomic), and since the atomic returns with a
direct branch, the caller's PC may be missing from the backtrace.
For example, with secondary_start_kernel() hacked to contain
atomic_inc(NULL), the resulting exception can be reported as being taken
from cpus_are_stuck_in_kernel():
The rationale was to improve icache performance by grouping the LL/SC
atomics together. This has never been measured, and this theoretical
benefit is outweighed by other factors:
* As the subsections are collapsed into sections at object file
granularity, these are spread out throughout the kernel and can share
cachelines with unrelated code regardless.
* GCC 12.1.0 has been observed to place the trampoline out-of-line in
specialised __ll_sc_*() functions, introducing more branching than was
intended.
* Removing the trampolines has been observed to shrink a defconfig
kernel Image by 64KiB when building with GCC 12.1.0.
This patch removes the LL/SC trampolines, meaning that the LL/SC atomics
will be inlined into their callers (or placed in out-of line functions
using regular BL/RET pairs). When CONFIG_ARM64_LSE_ATOMICS=y, the LL/SC
atomics are always called in an unlikely branch, and will be placed in a
cold portion of the function, so this should have minimal impact to the
hot paths.
Other than the improved backtracing, there should be no functional
change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20220817155914.3975112-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Stable-dep-of: 031af50045ea ("arm64: cmpxchg_double*: hazard against entire exchange variable") Signed-off-by: Sasha Levin <sashal@kernel.org>
This patch makes the indentation consistent and also aligns the trailing
backslashes. This makes the code easier to read for those (like myself)
who are easily distracted by these inconsistencies.
This is intended as a cleanup.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20211210151410.2782645-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Stable-dep-of: 031af50045ea ("arm64: cmpxchg_double*: hazard against entire exchange variable") Signed-off-by: Sasha Levin <sashal@kernel.org>
Userspace can guess the handle value and try to race GEM object creation
with handle close, resulting in a use-after-free if we dereference the
object after dropping the handle's reference. For that reason, dropping
the handle's reference must be done *after* we are done dereferencing
the object.
When the user moves a running task to a new rdtgroup using the task's
file interface or by deleting its rdtgroup, the resulting change in
CLOSID/RMID must be immediately propagated to the PQR_ASSOC MSR on the
task(s) CPUs.
x86 allows reordering loads with prior stores, so if the task starts
running between a task_curr() check that the CPU hoisted before the
stores in the CLOSID/RMID update then it can start running with the old
CLOSID/RMID until it is switched again because __rdtgroup_move_task()
failed to determine that it needs to be interrupted to obtain the new
CLOSID/RMID.
Refer to the diagram below:
CPU 0 CPU 1
----- -----
__rdtgroup_move_task():
curr <- t1->cpu->rq->curr
__schedule():
rq->curr <- t1
resctrl_sched_in():
t1->{closid,rmid} -> {1,1}
t1->{closid,rmid} <- {2,2}
if (curr == t1) // false
IPI(t1->cpu)
A similar race impacts rdt_move_group_tasks(), which updates tasks in a
deleted rdtgroup.
In both cases, use smp_mb() to order the task_struct::{closid,rmid}
stores before the loads in task_curr(). In particular, in the
rdt_move_group_tasks() case, simply execute an smp_mb() on every
iteration with a matching task.
It is possible to use a single smp_mb() in rdt_move_group_tasks(), but
this would require two passes and a means of remembering which
task_structs were updated in the first loop. However, benchmarking
results below showed too little performance impact in the simple
approach to justify implementing the two-pass approach.
Times below were collected using `perf stat` to measure the time to
remove a group containing a 1600-task, parallel workload.
CPU: Intel(R) Xeon(R) Platinum P-8136 CPU @ 2.00GHz (112 threads)
James reported in [1] that there could be two tasks running on the same CPU
with task_struct->on_cpu set. Using task_struct->on_cpu as a test if a task
is running on a CPU may thus match the old task for a CPU while the
scheduler is running and IPI it unnecessarily.
task_curr() is the correct helper to use. While doing so move the #ifdef
check of the CONFIG_SMP symbol to be a C conditional used to determine
if this helper should be used to ensure the code is always checked for
correctness by the compiler.
.max_adj of ptp_clock_info acts as an absolute value for the amount in ppb
that can be set for a single call of .adjfine. This means that a single
call to .getfine cannot be greater than .max_adj or less than -(.max_adj).
Provides correct value for max frequency adjustment value supported by
devices.
Fix a typo in ptp_clock_info naming: mlx5_p2p -> mlx5_ptp.
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Stable-dep-of: fe91d57277ee ("net/mlx5: Fix ptp max frequency adjustment range") Signed-off-by: Sasha Levin <sashal@kernel.org>
The 'TCA_MPLS_LABEL' attribute is of 'NLA_U32' type, but has a
validation type of 'NLA_VALIDATE_FUNCTION'. This is an invalid
combination according to the comment above 'struct nla_policy':
"
Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN:
NLA_BINARY Validation function called for the attribute.
All other Unused - but note that it's a union
"
This can trigger the warning [1] in nla_get_range_unsigned() when
validation of the attribute fails. Despite being of 'NLA_U32' type, the
associated 'min'/'max' fields in the policy are negative as they are
aliased by the 'validate' field.
Fix by changing the attribute type to 'NLA_BINARY' which is consistent
with the above comment and all other users of NLA_POLICY_VALIDATE_FN().
As a result, move the length validation to the validation function.
Fix a use-after-free that occurs in hcd when in_urb sent from
pn533_usb_send_frame() is completed earlier than out_urb. Its callback
frees the skb data in pn533_send_async_complete() that is used as a
transfer buffer of out_urb. Wait before sending in_urb until the
callback of out_urb is called. To modify the callback of out_urb alone,
separate the complete function of out_urb and ack_urb.
The currently lockless access to the xen console list in
vtermno_to_xencons() is incorrect, as additions and removals from the
list can happen anytime, and as such the traversal of the list to get
the private console data for a given termno needs to happen with the
lock held. Note users that modify the list already do so with the
lock taken.
Adjust current lock takers to use the _irq{save,restore} helpers,
since the context in which vtermno_to_xencons() is called can have
interrupts disabled. Use the _irq{save,restore} set of helpers to
switch the current callers to disable interrupts in the locked region.
I haven't checked if existing users could instead use the _irq
variant, as I think it's safer to use _irq{save,restore} upfront.
While there switch from using list_for_each_entry_safe to
list_for_each_entry: the current entry cursor won't be removed as
part of the code in the loop body, so using the _safe variant is
pointless.
node 1 | node 2
------ | ------
link is established | link is established
reboot | link is reset
up | send discovery message
receive discovery message |
link is established | link is established
send discovery message |
| receive discovery message
| link is reset (unexpected)
| send reset message
link is reset |
It is due to delayed re-discovery as described in function
tipc_node_check_dest(): "this link endpoint has already reset
and re-established contact with the peer, before receiving a
discovery message from that node."
However, commit 598411d70f85 has changed the condition for calling
tipc_node_link_down() which was the acceptance of new media address.
This commit fixes this by restoring the old and correct behavior.
Fixes: 598411d70f85 ("tipc: make resetting of links non-atomic") Acked-by: Jon Maloy <jmaloy@redhat.com> Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently, we scan over all network namespaces at each received
discovery message in order to check if the sending peer might be
present in a host local namespaces.
This is unnecessary since we can assume that a peer will not change its
location during an established session.
We now improve the condition for this testing so that we don't perform
any redundant scans.
Fixes: f73b12812a3d ("tipc: improve throughput between nodes in netns") Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: c244c092f1ed ("tipc: fix unexpected link reset due to discovery messages") Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently, TIPC transports intra-node user data messages directly
socket to socket, hence shortcutting all the lower layers of the
communication stack. This gives TIPC very good intra node performance,
both regarding throughput and latency.
We now introduce a similar mechanism for TIPC data traffic across
network namespaces located in the same kernel. On the send path, the
call chain is as always accompanied by the sending node's network name
space pointer. However, once we have reliably established that the
receiving node is represented by a namespace on the same host, we just
replace the namespace pointer with the receiving node/namespace's
ditto, and follow the regular socket receive patch though the receiving
node. This technique gives us a throughput similar to the node internal
throughput, several times larger than if we let the traffic go though
the full network stacks. As a comparison, max throughput for 64k
messages is four times larger than TCP throughput for the same type of
traffic.
To meet any security concerns, the following should be noted.
- All nodes joining a cluster are supposed to have been be certified
and authenticated by mechanisms outside TIPC. This is no different for
nodes/namespaces on the same host; they have to auto discover each
other using the attached interfaces, and establish links which are
supervised via the regular link monitoring mechanism. Hence, a kernel
local node has no other way to join a cluster than any other node, and
have to obey to policies set in the IP or device layers of the stack.
- Only when a sender has established with 100% certainty that the peer
node is located in a kernel local namespace does it choose to let user
data messages, and only those, take the crossover path to the receiving
node/namespace.
- If the receiving node/namespace is removed, its namespace pointer
is invalidated at all peer nodes, and their neighbor link monitoring
will eventually note that this node is gone.
- To ensure the "100% certainty" criteria, and prevent any possible
spoofing, received discovery messages must contain a proof that the
sender knows a common secret. We use the hash mix of the sending
node/namespace for this purpose, since it can be accessed directly by
all other namespaces in the kernel. Upon reception of a discovery
message, the receiver checks this proof against all the local
namespaces'hash_mix:es. If it finds a match, that, along with a
matching node id and cluster id, this is deemed sufficient proof that
the peer node in question is in a local namespace, and a wormhole can
be opened.
- We should also consider that TIPC is intended to be a cluster local
IPC mechanism (just like e.g. UNIX sockets) rather than a network
protocol, and hence we think it can justified to allow it to shortcut the
lower protocol layers.
Regarding traceability, we should notice that since commit 6c9081a3915d
("tipc: add loopback device tracking") it is possible to follow the node
internal packet flow by just activating tcpdump on the loopback
interface. This will be true even for this mechanism; by activating
tcpdump on the involved nodes' loopback interfaces their inter-name
space messaging can easily be tracked.
v2:
- update 'net' pointer when node left/rejoined
v3:
- grab read/write lock when using node ref obj
v4:
- clone traffics between netns to loopback
Suggested-by: Jon Maloy <jon.maloy@ericsson.com> Acked-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: c244c092f1ed ("tipc: fix unexpected link reset due to discovery messages") Signed-off-by: Sasha Levin <sashal@kernel.org>
With 'GNU assembler (GNU Binutils for Debian) 2.39.90.20221231' the
build now reports:
arch/x86/realmode/rm/../../boot/bioscall.S: Assembler messages:
arch/x86/realmode/rm/../../boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant
arch/x86/realmode/rm/../../boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant
arch/x86/boot/bioscall.S: Assembler messages:
arch/x86/boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant
arch/x86/boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant
Which is due to:
PR gas/29525
Note that with the dropped CMPSD and MOVSD Intel Syntax string insn
templates taking operands, mixed IsString/non-IsString template groups
(with memory operands) cannot occur anymore. With that
maybe_adjust_templates() becomes unnecessary (and is hence being
removed).
More details: https://sourceware.org/bugzilla/show_bug.cgi?id=29525
Borislav Petkov further explains:
" the particular problem here is is that the 'd' suffix is
"conflicting" in the sense that you can have SSE mnemonics like movsD %xmm...
and the same thing also for string ops (which is the case here) so apparently
the agreement in binutils land is to use the always accepted suffixes 'l' or 'q'
and phase out 'd' slowly... "
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
preempt_count: 2, expected: 0
4 locks held by perf-exec/2869:
#0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
#1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
#2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
#3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
irq event stamp: 4806
hardirqs last enabled at (4805): [<c000000000f65b94>] _raw_spin_unlock_irqrestore+0x94/0xd0
hardirqs last disabled at (4806): [<c0000000003fae44>] perf_event_exec+0x394/0x510
softirqs last enabled at (0): [<c00000000013c404>] copy_process+0xc34/0x1ff0
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
Call Trace:
dump_stack_lvl+0x98/0xe0 (unreliable)
__might_resched+0x2f8/0x310
__mutex_lock+0x6c/0x13f0
thread_imc_event_add+0xf4/0x1b0
event_sched_in+0xe0/0x210
merge_sched_in+0x1f0/0x600
visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
ctx_flexible_sched_in+0xcc/0x140
ctx_sched_in+0x20c/0x2a0
ctx_resched+0x104/0x1c0
perf_event_exec+0x340/0x510
begin_new_exec+0x730/0xef0
load_elf_binary+0x3f8/0x1e10
...
do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0
WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2)
MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 48002824 XER: 00000000
CFAR: c00000000013fb64 IRQMASK: 1
The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.
Fix the issue by changing the mutex lock to spinlock.
Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device") Reported-by: Michael Petlan <mpetlan@redhat.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
[mpe: Fix comments, trim oops in change log, add reported-by tags] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When first_ip is 0, last_ip is 0xFFFFFFFF, and netmask is 31, the value of
an arithmetic expression 2 << (netmask - mask_bits - 1) is subject
to overflow due to a failure casting operands to a larger data type
before performing the arithmetic.
Note that it's harmless since the value will be checked at the next step.
Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.
Fixes: b9fed748185a ("netfilter: ipset: Check and reject crazy /0 input parameters") Signed-off-by: Ilia.Gavrilov <Ilia.Gavrilov@infotecs.ru> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CPU: 1 PID: 4625 Comm: syz-executor.2 Not tainted 6.1.0-rc4-syzkaller-62821-gcb231e2f67ec #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
=====================================================
Now, 'ext4_alloc_inode()' didn't init 'ei->i_flags'. If new inode failed
before set 'ei->i_flags' in '__ext4_new_inode()', then do 'iput()'. As after 6bc0d63dad7f commit will access 'ei->i_flags' in 'ext4_evict_inode()' which
will lead to access uninit-value.
To solve above issue just init 'ei->i_flags' in 'ext4_alloc_inode()'.
Reported-by: syzbot+57b25da729eb0b88177d@syzkaller.appspotmail.com Signed-off-by: Ye Bin <yebin10@huawei.com> Fixes: 6bc0d63dad7f ("ext4: remove EA inode entry from mbcache on inode eviction") Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221117073603.2598882-1-yebin@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
I caught a issue as follows:
==================================================================
BUG: KASAN: use-after-free in __list_add_valid+0x28/0x1a0
Read of size 8 at addr ffff88814b13f378 by task mount/710
Above issue may happen as follows:
-------------------------------------
ext4_fill_super
ext4_orphan_cleanup
ext4_enable_quotas
ext4_quota_enable
ext4_iget --> get error inode <5>
ext4_ext_check_inode --> Wrong imode makes it escape inspection
make_bad_inode(inode) --> EXT4_BOOT_LOADER_INO set imode
dquot_load_quota_inode
vfs_setup_quota_inode --> check pass
dquot_load_quota_sb
v2_check_quota_file
v2_read_header
ext4_quota_read
ext4_bread
ext4_getblk
ext4_map_blocks
ext4_ext_map_blocks
ext4_find_extent
ext4_cache_extents
ext4_es_cache_extent
__es_tree_search.isra.0
ext4_es_end --> Wrong extents trigger BUG_ON
In the above issue, s_usr_quota_inum is set to 5, but inode<5> contains
incorrect imode and disordered extents. Because 5 is EXT4_BOOT_LOADER_INO,
the ext4_ext_check_inode check in the ext4_iget function can be bypassed,
finally, the extents that are not checked trigger the BUG_ON in the
__es_tree_search function. To solve this issue, check whether the inode is
bad_inode in vfs_setup_quota_inode().
Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Jason Yan <yanaijie@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20221026042310.3839669-2-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
Factor out setting up of quota inode and eventual error cleanup from
vfs_load_quota_inode(). This will simplify situation for filesystems
that don't have any quota inodes.
Signed-off-by: Jan Kara <jack@suse.cz>
Stable-dep-of: d32387748476 ("ext4: fix bug_on in __es_tree_search caused by bad quota inode") Signed-off-by: Sasha Levin <sashal@kernel.org>
The print format error was found when using ftrace event:
<...>-1406 [000] .... 23599442.895823: jbd2_end_commit: dev 252,8 transaction -1866216965 sync 0 head -1866217368
<...>-1406 [000] .... 23599442.896299: jbd2_start_commit: dev 252,8 transaction -1866216964 sync 0
Use the correct print format for transaction, head and tid.
Fixes: 879c5e6b7cb4 ('jbd2: convert instrumentation from markers to tracepoints') Signed-off-by: Bixuan Cui <cuibixuan@linux.alibaba.com> Reviewed-by: Jason Yan <yanaijie@huawei.com> Link: https://lore.kernel.org/r/1665488024-95172-1-git-send-email-cuibixuan@linux.alibaba.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
Since commit 0f0101719138 ("usb: dwc3: Don't switch OTG -> peripheral
if extcon is present") Dual Role support on Intel Merrifield platform
broke due to rearranging the call to dwc3_get_extcon().
It appears to be caused by ulpi_read_id() on the first test write failing
with -ETIMEDOUT. Currently ulpi_read_id() expects to discover the phy via
DT when the test write fails and returns 0 in that case, even if DT does not
provide the phy. As a result usb probe completes without phy.
Make ulpi_read_id() return -ETIMEDOUT to its user if the first test write
fails. The user should then handle it appropriately. A follow up patch
will make dwc3_core_init() set -EPROBE_DEFER in this case and bail out.
Fixes: ef6a7bcfb01c ("usb: ulpi: Support device discovery via DT") Cc: stable@vger.kernel.org Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Ferry Toth <ftoth@exalondelft.nl> Link: https://lore.kernel.org/r/20221205201527.13525-2-ftoth@exalondelft.nl Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The total cork length created by ip6_append_data includes extension
headers, so we must exclude them when comparing them against the
IPV6_CHECKSUM offset which does not include extension headers.
Reported-by: Kyle Zeng <zengyhkyle@gmail.com> Fixes: 357b40a18b04 ("[IPV6]: IPV6_CHECKSUM socket option can corrupt kernel memory") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As the comment of pci_get_domain_bus_and_slot() says, it
returns a PCI device with refcount incremented, when finish
using it, the caller must decrement the reference count by
calling pci_dev_put().
In ixgbe_get_first_secondary_devfn() and ixgbe_x550em_a_has_mii(),
pci_dev_put() is called to avoid leak.
Fixes: 8fa10ef01260 ("ixgbe: register a mdiobus") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel) Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
So far the adreno quirks have all been assigned with an OR operator,
which is problematic, because they were assigned consecutive integer
values, which makes checking them with an AND operator kind of no bueno..
Switch to using BIT(n) so that only the quirks that the programmer chose
are taken into account when evaluating info->quirks & ADRENO_QUIRK_...
Fixes: 370063ee427a ("drm/msm/adreno: Add A540 support") Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org> Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org> Reviewed-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/516456/ Link: https://lore.kernel.org/r/20230102100201.77286-1-konrad.dybcio@linaro.org Signed-off-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If smb311 posix is enabled, we send the intended mode for file
creation in the posix create context. Instead of using what's there on
the stack, create the mfsymlink file with 0644.
Fixes: ce558b0e17f8a ("smb3: Add posix create context for smb3.11 posix mounts") Cc: stable@vger.kernel.org Signed-off-by: Volker Lendecke <vl@samba.org> Reviewed-by: Tom Talpey <tom@talpey.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clement Lecigne [Fri, 13 Jan 2023 12:07:45 +0000 (13:07 +0100)]
ALSA: pcm: Move rwsem lock inside snd_ctl_elem_read to prevent UAF
[ Note: this is a fix that works around the bug equivalently as the
two upstream commits: 1fa4445f9adf ("ALSA: control - introduce snd_ctl_notify_one() helper") 56b88b50565c ("ALSA: pcm: Move rwsem lock inside snd_ctl_elem_read to prevent UAF")
but in a simpler way to fit with older stable trees -- tiwai ]
Add missing locking in ctl_elem_read_user/ctl_elem_write_user which can be
easily triggered and turned into an use-after-free.
Example code paths with SNDRV_CTL_IOCTL_ELEM_READ:
Make sure that *ptr__ within arch_this_cpu_to_op_simple() is only
dereferenced once by using READ_ONCE(). Otherwise the compiler could
generate incorrect code.
This commit addresses the following erroneous situation with file-based
kdump executed on a system with a valid IPL report.
On s390, a kdump kernel, its initrd and IPL report if present are loaded
into a special and reserved on boot memory region - crashkernel. When
a system crashes and kdump was activated before, the purgatory code
is entered first which swaps the crashkernel and [0 - crashkernel size]
memory regions. Only after that the kdump kernel is entered. For this
reason, the pointer to an IPL report in lowcore must point to the IPL report
after the swap and not to the address of the IPL report that was located in
crashkernel memory region before the swap. Failing to do so, makes the
kdump's decompressor try to read memory from the crashkernel memory region
which already contains the production's kernel memory.
The situation described above caused spontaneous kdump failures/hangs
on systems where the Secure IPL is activated because on such systems
an IPL report is always present. In that case kdump's decompressor tried
to parse an IPL report which frequently lead to illegal memory accesses
because an IPL report contains addresses to various data.
Cc: <stable@vger.kernel.org> Fixes: 99feaa717e55 ("s390/kexec_file: Create ipl report and pass to next kernel") Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
$ gcc -Wall -Wextra -o test file1.c file2.c
$ perf record -e intel_pt//u --filter 'filter func @ ./test' -- ./test
Multiple symbols with name 'func'
#1 0x1149 l func
which is near main
#2 0x1179 l func
which is near other
Disambiguate symbol name by inserting #n after the name e.g. func #2
Or select a global symbol by inserting #0 or #g or #G
Failed to parse address filter: 'filter func @ ./test'
Filter format is: filter|start|stop|tracestop <start symbol or address> [/ <end symbol or size>] [@<file name>]
Where multiple filters are separated by space or comma.
$ perf record -e intel_pt//u --filter 'filter func #2 @ ./test' -- ./test
Failed to parse address filter: 'filter func #2 @ ./test'
Filter format is: filter|start|stop|tracestop <start symbol or address> [/ <end symbol or size>] [@<file name>]
Where multiple filters are separated by space or comma.
Sphinx 6.0 removed the execfile_() function, which we use as part of the
configuration process. They *did* warn us... Just open-code the
functionality as is done in Sphinx itself.
Tested (using SPHINX_CONF, since this code is only executed with an
alternative config file) on various Sphinx versions from 2.5 through 6.0.
Reported-by: Martin Liška <mliska@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nathan reports that recent kernels built with LTO will crash when doing
EFI boot using Fedora's GRUB and SHIM. The culprit turns out to be a
misaligned load from the TPM event log, which is annotated with
READ_ONCE(), and under LTO, this gets translated into a LDAR instruction
which does not tolerate misaligned accesses.
Interestingly, this does not happen when booting the same kernel
straight from the UEFI shell, and so the fact that the event log may
appear misaligned in memory may be caused by a bug in GRUB or SHIM.
However, using READ_ONCE() to access firmware tables is slightly unusual
in any case, and here, we only need to ensure that 'event' is not
dereferenced again after it gets unmapped, but this is already taken
care of by the implicit barrier() semantics of the early_memunmap()
call.
Cc: <stable@vger.kernel.org> Cc: Peter Jones <pjones@redhat.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Reported-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://github.com/ClangBuiltLinux/linux/issues/1782 Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A recent development on the EFI front has resulted in guests having
their page tables baked in the firmware binary, and mapped into the
IPA space as part of a read-only memslot. Not only is this legitimate,
but it also results in added security, so thumbs up.
It is possible to take an S1PTW translation fault if the S1 PTs are
unmapped at stage-2. However, KVM unconditionally treats S1PTW as a
write to correctly handle hardware AF/DB updates to the S1 PTs.
Furthermore, KVM injects an exception into the guest for S1PTW writes.
In the aforementioned case this results in the guest taking an abort
it won't recover from, as the S1 PTs mapping the vectors suffer from
the same problem.
So clearly our handling is... wrong.
Instead, switch to a two-pronged approach:
- On S1PTW translation fault, handle the fault as a read
- On S1PTW permission fault, handle the fault as a write
This is of no consequence to SW that *writes* to its PTs (the write
will trigger a non-S1PTW fault), and SW that uses RO PTs will not
use HW-assisted AF/DB anyway, as that'd be wrong.
Only in the case described in c4ad98e4b72c ("KVM: arm64: Assume write
fault on S1PTW permission fault on instruction fetch") do we end-up
with two back-to-back faults (page being evicted and faulted back).
I don't think this is a case worth optimising for.
Fixes: c4ad98e4b72c ("KVM: arm64: Assume write fault on S1PTW permission fault on instruction fetch") Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Regression-tested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While experimenting with applying noqueue to a classful queue discipline,
we discovered a NULL pointer dereference in the __dev_queue_xmit()
path that generates a kernel OOPS:
Previously in commit d66d6c3152e8 ("net: sched: register noqueue
qdisc"), NULL was set for the noqueue discipline on noqueue init
so that __dev_queue_xmit() falls through for the noqueue case. This
also sets a bypass of the enqueue NULL check in the
register_qdisc() function for the struct noqueue_disc_ops.
Classful queue disciplines make it past the NULL check in
__dev_queue_xmit() because the discipline is set to htb (in this case),
and then in the call to __dev_xmit_skb(), it calls into htb_enqueue()
which grabs a leaf node for a class and then calls qdisc_enqueue() by
passing in a queue discipline which assumes ->enqueue() is not set to NULL.
Fix this by not allowing classes to be assigned to the noqueue
discipline. Linux TC Notes states that classes cannot be set to
the noqueue discipline. [1] Let's enforce that here.
When a driver registers with a bus, it will attempt to match with every
device on the bus through the __driver_attach() function. Currently, if
the bus_type.match() function encounters an error that is not
-EPROBE_DEFER, __driver_attach() will return a negative error code, which
causes the driver registration logic to stop trying to match with the
remaining devices on the bus.
This behavior is not correct; a failure while matching a driver to a
device does not mean that the driver won't be able to match and bind
with other devices on the bus. Update the logic in __driver_attach()
to reflect this.
Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()") Cc: stable@vger.kernel.org Cc: Saravana Kannan <saravanak@google.com> Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com> Link: https://lore.kernel.org/r/20220921001414.4046492-1-isaacmanjarres@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The build of kselftests fails if relative path is specified through
KBUILD_OUTPUT or O=<path> method. BUILD variable is used to determine
the path of the output objects. When make is run from other directories
with relative paths, the exact path of the build objects is ambiguous
and build fails.
Set the BUILD variable to the absolute path of the output directory.
Make the logic readable and easy to follow. Use spaces instead of tabs
for indentation as if with tab indentation is considered recipe in make.
make kselftest-all O=objdir builds create generated objects in objdir.
This clutters the top level directory with kselftest objects. Fix it
to create sub-directory under objdir for kselftest objects.
Adjust some MADV_XXX constants to be in sync what their values are on
all other platforms. There is currently no reason to have an own
numbering on parisc, but it requires workarounds in many userspace
sources (e.g. glibc, qemu, ...) - which are often forgotten and thus
introduce bugs and different behaviour on parisc.
A wrapper avoids an ABI breakage for existing userspace applications by
translating any old values to the new ones, so this change allows us to
move over all programs to the new ABI over time.
Commit 307af6c87937 ("mbcache: automatically delete entries from cache
on freeing") started nesting cache->c_list_lock under the bit locks
protecting hash buckets of the mbcache hash table in
mb_cache_entry_create(). This causes problems for real-time kernels
because there spinlocks are sleeping locks while bitlocks stay atomic.
Luckily the nesting is easy to avoid by holding entry reference until
the entry is added to the LRU list. This makes sure we cannot race with
entry deletion.
Cc: stable@kernel.org Fixes: 307af6c87937 ("mbcache: automatically delete entries from cache on freeing") Reported-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220908091032.10513-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 55d1cbbbb29e ("hfs/hfsplus: use WARN_ON for sanity check") fixed
a build warning by turning a comment into a WARN_ON(), but it turns out
that syzbot then complains because it can trigger said warning with a
corrupted hfs image.
The warning actually does warn about a bad situation, but we are much
better off just handling it as the error it is. So rather than warn
about us doing bad things, stop doing the bad things and return -EIO.
While at it, also fix a memory leak that was introduced by an earlier
fix for a similar syzbot warning situation, and add a check for one case
that historically wasn't handled at all (ie neither comment nor
subsequent WARN_ON).
Reported-by: syzbot+7bb7cd3595533513a9e7@syzkaller.appspotmail.com Fixes: 55d1cbbbb29e ("hfs/hfsplus: use WARN_ON for sanity check") Fixes: 8d824e69d9f3 ("hfs: fix OOB Read in __hfs_brec_find") Link: https://lore.kernel.org/lkml/000000000000dbce4e05f170f289@google.com/ Tested-by: Michael Schmitz <schmitzmic@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gcc warns about a couple of instances in which a sanity check exists but
the author wasn't sure how to react to it failing, which makes it look
like a possible bug:
fs/hfsplus/inode.c: In function 'hfsplus_cat_read_inode':
fs/hfsplus/inode.c:503:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
503 | /* panic? */;
| ^
fs/hfsplus/inode.c:524:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
524 | /* panic? */;
| ^
fs/hfsplus/inode.c: In function 'hfsplus_cat_write_inode':
fs/hfsplus/inode.c:582:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
582 | /* panic? */;
| ^
fs/hfsplus/inode.c:608:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
608 | /* panic? */;
| ^
fs/hfs/inode.c: In function 'hfs_write_inode':
fs/hfs/inode.c:464:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
464 | /* panic? */;
| ^
fs/hfs/inode.c:485:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
485 | /* panic? */;
| ^
panic() is probably not the correct choice here, but a WARN_ON
seems appropriate and avoids the compile-time warning.
Link: https://lkml.kernel.org/r/20210927102149.1809384-1-arnd@kernel.org Link: https://lore.kernel.org/all/20210322223249.2632268-1-arnd@kernel.org/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mounting a filesystem whose journal inode has the encrypt flag causes a
NULL dereference in fscrypt_limit_io_blocks() when the 'inlinecrypt'
mount option is used.
The problem is that when jbd2_journal_init_inode() calls bmap(), it
eventually finds its way into ext4_iomap_begin(), which calls
fscrypt_limit_io_blocks(). fscrypt_limit_io_blocks() requires that if
the inode is encrypted, then its encryption key must already be set up.
That's not the case here, since the journal inode is never "opened" like
a normal file would be. Hence the crash.
To fix this, make ext4 consider journal inodes with the encrypt flag to
be invalid. (Note, maybe other flags should be rejected on the journal
inode too. For now, this is just the minimal fix for the above issue.)
I've marked this as fixing the commit that introduced the call to
fscrypt_limit_io_blocks(), since that's what made an actual crash start
being possible. But this fix could be applied to any version of ext4
that supports the encrypt feature.
Reported-by: syzbot+ba9dac45bc76c490b7c3@syzkaller.appspotmail.com Fixes: 38ea50daa7a4 ("ext4: support direct I/O with fscrypt using blk-crypto") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20221102053312.189962-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the get_user(x, ptr) has x as a pointer, then the setting
of (x) = 0 is going to produce the following sparse warning,
so fix this by forcing the type of 'x' when access_ok() fails.
fs/aio.c:2073:21: warning: Using plain integer as NULL pointer
If v4 READDIR operation hits a mountpoint and gets back an error,
then it will include that entry in the reply and set RDATTR_ERROR for it
to the error.
That's fine for "normal" exported filesystems, but on the v4root, we
need to be more careful to only expose the existence of dentries that
lead to exports.
If the mountd upcall times out while checking to see whether a
mountpoint on the v4root is exported, then we have no recourse other
than to fail the whole operation.
Cc: Steve Dickson <steved@redhat.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216777 Reported-by: JianHong Yin <yin-jianhong@163.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Advantech MICA-071 tablet deviates from the defaults for
a non CR Bay Trail based tablet in several ways:
1. It uses an analog MIC on IN3 rather then using DMIC1
2. It only has 1 speaker
3. It needs the OVCD current threshold to be set to 1500uA instead of
the default 2000uA to reliable differentiate between headphones vs
headsets
Add a quirk with these settings for this tablet.
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Link: https://lore.kernel.org/r/20221213123246.11226-1-hdegoede@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When extending the last extent in the file within the last block, we
wrongly computed the length of the last extent. This is mostly a
cosmetical problem since the extent does not contain any data and the
length will be fixed up by following operations but still.
Fixes: 1f3868f06855 ("udf: Fix extending file within last block") Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>
Variables off and len typed as uint32 in rndis_query function
are controlled by incoming RNDIS response message thus their
value may be manipulated. Setting off to a unexpectetly large
value will cause the sum with len and 8 to overflow and pass
the implemented validation step. Consequently the response
pointer will be referring to a location past the expected
buffer boundaries allowing information leakage e.g. via
RNDIS_OID_802_3_PERMANENT_ADDRESS OID.
Fixes: ddda08624013 ("USB: rndis_host, various cleanups") Signed-off-by: Szymon Heidrich <szymon.heidrich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
If asked to drop a packet via TC_ACT_SHOT it is unsafe to assume
res.class contains a valid pointer Fixes: b0188d4dbe5f ("[NET_SCHED]: sch_atm: Lindent") Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently, when modifying DC, we validate max_rd_atomic user attribute
against the RC cap, validate against DC. RC and DC QP types have different
device limitations.
This can cause userspace created DC QPs to malfunction.
of_phy_find_device() return device node with refcount incremented.
Call put_device() to relese it when not needed anymore.
Fixes: ab4e6ee578e8 ("net: phy: xgmiitorgmii: Check phy_driver ready before accessing") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
The driver does not call tasklet_kill in several places.
Add the calls to fix it.
Fixes: 85b85c853401 ("amd-xgbe: Re-issue interrupt if interrupt status not cleared") Signed-off-by: Jiguang Xiao <jiguang.xiao@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
vhost_iotlb_itree_first() requires `start` and `last` parameters
to search for a mapping that overlaps the range.
In translate_desc() we cyclically call vhost_iotlb_itree_first(),
incrementing `addr` by the amount already translated, so rightly
we move the `start` parameter passed to vhost_iotlb_itree_first(),
but we should hold the `last` parameter constant.
Let's fix it by saving the `last` parameter value before incrementing
`addr` in the loop.
Fixes: a9709d6874d5 ("vhost: convert pre sorted vhost memory array to interval tree") Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20221109102503.18816-3-sgarzare@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
nfc_get_device() take reference for the device, add missing
nfc_put_device() to release it when not need anymore.
Also fix the style warnning by use error EOPNOTSUPP instead of
ENOTSUPP.
Fixes: 5ce3f32b5264 ("NFC: netlink: SE API implementation") Fixes: 29e76924cf08 ("nfc: netlink: Add capability to reply to vendor_cmd with data") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
adapter->dcb would get silently freed inside qlcnic_dcb_enable() in
case qlcnic_dcb_attach() would return an error, which always happens
under OOM conditions. This would lead to use-after-free because both
of the existing callers invoke qlcnic_dcb_get_info() on the obtained
pointer, which is potentially freed at that point.
Propagate errors from qlcnic_dcb_enable(), and instead free the dcb
pointer at callsite using qlcnic_dcb_free(). This also removes the now
unused qlcnic_clear_dcb_ops() helper, which was a simple wrapper around
kfree() also causing memory leaks for partially initialized dcb.
Found by Linux Verification Center (linuxtesting.org) with the SVACE
static analysis tool.
Fixes: 3c44bba1d270 ("qlcnic: Disable DCB operations from SR-IOV VFs") Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Kernel uses tcindex_change() to change an existing
filter properties.
Yet the problem is that, during the process of changing,
if `old_r` is retrieved from `p->perfect`, then
kernel uses tcindex_alloc_perfect_hash() to newly
allocate filter results, uses tcindex_filter_result_init()
to clear the old filter result, without destroying
its tcf_exts structure, which triggers the above memory leak.
To be more specific, there are only two source for the `old_r`,
according to the tcindex_lookup(). `old_r` is retrieved from
`p->perfect`, or `old_r` is retrieved from `p->h`.
* If `old_r` is retrieved from `p->perfect`, kernel uses
tcindex_alloc_perfect_hash() to newly allocate the
filter results. Then `r` is assigned with `cp->perfect + handle`,
which is newly allocated. So condition `old_r && old_r != r` is
true in this situation, and kernel uses tcindex_filter_result_init()
to clear the old filter result, without destroying
its tcf_exts structure
* If `old_r` is retrieved from `p->h`, then `p->perfect` is NULL
according to the tcindex_lookup(). Considering that `cp->h`
is directly copied from `p->h` and `p->perfect` is NULL,
`r` is assigned with `tcindex_lookup(cp, handle)`, whose value
should be the same as `old_r`, so condition `old_r && old_r != r`
is false in this situation, kernel ignores using
tcindex_filter_result_init() to clear the old filter result.
So only when `old_r` is retrieved from `p->perfect` does kernel use
tcindex_filter_result_init() to clear the old filter result, which
triggers the above memory leak.
Considering that there already exists a tc_filter_wq workqueue
to destroy the old tcindex_data by tcindex_partial_destroy_work()
at the end of tcindex_set_parms(), this patch solves
this memory leak bug by removing this old filter result
clearing part and delegating it to the tc_filter_wq workqueue.
Note that this patch doesn't introduce any other issues. If
`old_r` is retrieved from `p->perfect`, this patch just
delegates old filter result clearing part to the
tc_filter_wq workqueue; If `old_r` is retrieved from `p->h`,
kernel doesn't reach the old filter result clearing part, so
removing this part has no effect.
[Thanks to the suggestion from Jakub Kicinski, Cong Wang, Paolo Abeni
and Dmitry Vyukov]
Fixes: b9a24bb76bf6 ("net_sched: properly handle failure case of tcf_exts_init()") Link: https://lore.kernel.org/all/0000000000001de5c505ebc9ec59@google.com/ Reported-by: syzbot+232ebdbd36706c965ebf@syzkaller.appspotmail.com Tested-by: syzbot+232ebdbd36706c965ebf@syzkaller.appspotmail.com Cc: Cong Wang <cong.wang@bytedance.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Hawkins Jiawei <yin31149@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently keep alive message between PF and VF may be lost and the VF is
unalive in PF. So the VF will not do reset during PF FLR reset process.
This would make the allocated interrupt resources of VF invalid and VF
would't receive or respond to PF any more.
So this patch adds VF interrupts re-initialization during VF FLR for VF
recovery in above cases.
Fixes: 862d969a3a4d ("net: hns3: do VF's pci re-initialization while PF doing FLR") Signed-off-by: Jie Wang <wangjie125@huawei.com> Signed-off-by: Hao Lan <lanhao@huawei.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently, we shut down the filecache before trying to clean up the
stateids that depend on it. This leads to the kernel trying to free an
nfsd_file twice, and a refcount overput on the nf_mark.
Change the shutdown procedure to tear down all of the stateids prior
to shutting down the filecache.
Reported-and-tested-by: Wang Yugui <wangyugui@e16-tech.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Fixes: 5e113224c17e ("nfsd: nfsd_file cache entries should be per net namespace") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Anand hit a BUG() when pulling off headers on egress to a SW tunnel.
We get to skb_checksum_help() with an invalid checksum offset
(commit d7ea0d9df2a6 ("net: remove two BUG() from skb_checksum_help()")
converted those BUGs to WARN_ONs()).
He points out oddness in how skb_postpull_rcsum() gets used.
Indeed looks like we should pull before "postpull", otherwise
the CHECKSUM_PARTIAL fixup from skb_postpull_rcsum() will not
be able to do its job:
Commit 9130b8dbc6ac ("SUNRPC: allow for upcalls for the same uid
but different gss service") introduced `auth` argument to
__gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL
since it (and auth->service) was not (yet) determined.
When multiple upcalls with the same uid and different service are
ongoing, it could happen that __gss_find_upcall(), which returns the
first match found in the pipe->in_downcall list, could not find the
correct gss_msg corresponding to the downcall we are looking for.
Moreover, it might return a msg which is not sent to rpc.gssd yet.
We could see mount.nfs process hung in D state with multiple mount.nfs
are executed in parallel. The call trace below is of CentOS 7.9
kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/
elrepo kernel-ml-6.0.7-1.el7.
The scenario is like this. Let's say there are two upcalls for
services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe.
When rpc.gssd reads pipe to get the upcall msg corresponding to
service B from pipe->pipe and then writes the response, in
gss_pipe_downcall the msg corresponding to service A will be picked
because only uid is used to find the msg and it is before the one for
B in pipe->in_downcall. And the process waiting for the msg
corresponding to service A will be woken up.
Actual scheduing of that process might be after rpc.gssd processes the
next msg. In rpc_pipe_generic_upcall it clears msg->errno (for A).
The process is scheduled to see gss_msg->ctx == NULL and
gss_msg->msg.errno == 0, therefore it cannot break the loop in
gss_create_upcall and is never woken up after that.
This patch adds a simple check to ensure that a msg which is not
sent to rpc.gssd yet is not chosen as the matching upcall upon
receiving a downcall.
Signed-off-by: minoura makoto <minoura@valinux.co.jp> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Tested-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Cc: Trond Myklebust <trondmy@hammerspace.com> Fixes: 9130b8dbc6ac ("SUNRPC: allow for upcalls for same uid but different gss service") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
When manipulating xattr blocks, we can deadlock infinitely looping
inside ext4_xattr_block_set() where we constantly keep finding xattr
block for reuse in mbcache but we are unable to reuse it because its
reference count is too big. This happens because cache entry for the
xattr block is marked as reusable (e_reusable set) although its
reference count is too big. When this inconsistency happens, this
inconsistent state is kept indefinitely and so ext4_xattr_block_set()
keeps retrying indefinitely.
The inconsistent state is caused by non-atomic update of e_reusable bit.
e_reusable is part of a bitfield and e_reusable update can race with
update of e_referenced bit in the same bitfield resulting in loss of one
of the updates. Fix the problem by using atomic bitops instead.
This bug has been around for many years, but it became *much* easier
to hit after commit 65f8b80053a1 ("ext4: fix race when reusing xattr
blocks").
Cc: stable@vger.kernel.org Fixes: 6048c64b2609 ("mbcache: add reusable flag to cache entries") Fixes: 65f8b80053a1 ("ext4: fix race when reusing xattr blocks") Reported-and-tested-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com> Reported-by: Thilo Fromm <t-lo@linux.microsoft.com> Link: https://lore.kernel.org/r/c77bf00f-4618-7149-56f1-b8d1664b9d07@linux.microsoft.com/ Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20221123193950.16758-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
Use the fact that entries with elevated refcount are not removed from
the hash and just move removal of the entry from the hash to the entry
freeing time. When doing this we also change the generic code to hold
one reference to the cache entry, not two of them, which makes code
somewhat more obvious.
Later the code in ext4_xattr_block_set() finds out the block got freed
and cancels reusal of the block but the revoke stays canceled and so in
case of block reuse and journal replay the filesystem can get corrupted.
If the race works out slightly differently, we can also hit assertions
in the jbd2 code.
Fix the problem by making sure that once matching mbcache entry is
found, code dropping the last xattr block reference (or trying to modify
xattr block in place) waits until the mbcache entry reference is
dropped. This way code trying to reuse xattr block is protected from
someone trying to drop the last reference to xattr block.
Reported-and-tested-by: Ritesh Harjani <ritesh.list@gmail.com> CC: stable@vger.kernel.org Fixes: 82939d7999df ("ext4: convert to mbcache2") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220712105436.32204-5-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: a44e84a9b776 ("ext4: fix deadlock due to mbcache entry corruption") Signed-off-by: Sasha Levin <sashal@kernel.org>
Remove unnecessary else (and thus indentation level) from a code block
in ext4_xattr_block_set(). It will also make following code changes
easier. No functional changes.
CC: stable@vger.kernel.org Fixes: 82939d7999df ("ext4: convert to mbcache2") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220712105436.32204-4-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: a44e84a9b776 ("ext4: fix deadlock due to mbcache entry corruption") Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently we remove EA inode from mbcache as soon as its xattr refcount
drops to zero. However there can be pending attempts to reuse the inode
and thus refcount handling code has to handle the situation when
refcount increases from zero anyway. So save some work and just keep EA
inode in mbcache until it is getting evicted. At that moment we are sure
following iget() of EA inode will fail anyway (or wait for eviction to
finish and load things from the disk again) and so removing mbcache
entry at that moment is fine and simplifies the code a bit.
CC: stable@vger.kernel.org Fixes: 82939d7999df ("ext4: convert to mbcache2") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220712105436.32204-3-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: a44e84a9b776 ("ext4: fix deadlock due to mbcache entry corruption") Signed-off-by: Sasha Levin <sashal@kernel.org>
Add function mb_cache_entry_delete_or_get() to delete mbcache entry if
it is unused and also add a function to wait for entry to become unused
- mb_cache_entry_wait_unused(). We do not share code between the two
deleting function as one of them will go away soon.
CC: stable@vger.kernel.org Fixes: 82939d7999df ("ext4: convert to mbcache2") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220712105436.32204-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: a44e84a9b776 ("ext4: fix deadlock due to mbcache entry corruption") Signed-off-by: Sasha Levin <sashal@kernel.org>
Do not reclaim entries that are currently used by somebody from a
shrinker. Firstly, these entries are likely useful. Secondly, we will
need to keep such entries to protect pending increment of xattr block
refcount.
CC: stable@vger.kernel.org Fixes: 82939d7999df ("ext4: convert to mbcache2") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220712105436.32204-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: a44e84a9b776 ("ext4: fix deadlock due to mbcache entry corruption") Signed-off-by: Sasha Levin <sashal@kernel.org>
Working through a conversion to a call kmap_local_page() instead of
kmap() revealed many places where the pattern kmap/memcpy/kunmap
occurred.
Eric Biggers, Matthew Wilcox, Christoph Hellwig, Dan Williams, and Al
Viro all suggested putting this code into helper functions. Al Viro
further pointed out that these functions already existed in the iov_iter
code.[1]
Various locations for the lifted functions were considered.
Headers like mm.h or string.h seem ok but don't really portray the
functionality well. pagemap.h made some sense but is for page cache
functionality.[2]
Another alternative would be to create a new header for the promoted
memcpy functions, but it masks the fact that these are designed to copy
to/from pages using the kernel direct mappings and complicates matters
with a new header.
Placing these functions in 'highmem.h' is suboptimal especially with the
changes being proposed in the functionality of kmap. From a caller
perspective including/using 'highmem.h' implies that the functions
defined in that header are only required when highmem is in use which is
increasingly not the case with modern processors. However, highmem.h is
where all the current functions like this reside (zero_user(),
clear_highpage(), clear_user_highpage(), copy_user_highpage(), and
copy_highpage()). So it makes the most sense even though it is
distasteful for some.[3]
Lift memcpy_to_page() and memcpy_from_page() to pagemap.h.
Cc: Boris Pismenny <borisp@mellanox.com> Cc: Or Gerlitz <gerlitz.or@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Suggested-by: Christoph Hellwig <hch@infradead.org> Suggested-by: Dan Williams <dan.j.williams@intel.com> Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Suggested-by: Eric Biggers <ebiggers@kernel.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 956510c0c743 ("fs: ext4: initialize fsdata in pagecache_write()") Signed-off-by: Sasha Levin <sashal@kernel.org>
When we used the journal_async_commit mounting option in nojournal mode,
the kernel told me that "can't mount with journal_checksum", was very
confusing. I find that when we mount with journal_async_commit, both the
JOURNAL_ASYNC_COMMIT and EXPLICIT_JOURNAL_CHECKSUM flags are set. However,
in the error branch, CHECKSUM is checked before ASYNC_COMMIT. As a result,
the above inconsistency occurs, and the ASYNC_COMMIT branch becomes dead
code that cannot be executed. Therefore, we exchange the positions of the
two judgments to make the error msg more accurate.
Before these two branches neither loaded the journal nor created the
xattr cache. So the right label to goto is 'failed_mount3a'. Although
this did not cause any issues because the error handler validated if the
pointer is null. However this still made me confused when reading
the code. So it's still worth to modify to goto the right label.
Signed-off-by: Jason Yan <yanaijie@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://lore.kernel.org/r/20220916141527.1012715-2-yanaijie@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: 89481b5fa8c0 ("ext4: correct inconsistent error msg in nojournal mode") Signed-off-by: Sasha Levin <sashal@kernel.org>
Consider the call to unregister_netdev()
unregister_netdev->unregister_netdevice_queue->rollback_registered_many
that calls the below functions which access the registers after
pm_runtime_put_sync()
1) ravb_get_stats
2) ravb_close
Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") Cc: stable@vger.kernel.org Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Link: https://lore.kernel.org/r/20221214105118.2495313-1-biju.das.jz@bp.renesas.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Set ENABLE_USR_WAIT_PAUSE in KVM's supported VMX MSR configuration if the
feature is supported in hardware and enabled in KVM's base, non-nested
configuration, i.e. expose ENABLE_USR_WAIT_PAUSE to L1 if it's supported.
This fixes a bug where saving/restoring, i.e. migrating, a vCPU will fail
if WAITPKG (the associated CPUID feature) is enabled for the vCPU, and
obviously allows L1 to enable the feature for L2.
KVM already effectively exposes ENABLE_USR_WAIT_PAUSE to L1 by stuffing
the allowed-1 control ina vCPU's virtual MSR_IA32_VMX_PROCBASED_CTLS2 when
updating secondary controls in response to KVM_SET_CPUID(2), but (a) that
depends on flawed code (KVM shouldn't touch VMX MSRs in response to CPUID
updates) and (b) runs afoul of vmx_restore_control_msr()'s restriction
that the guest value must be a strict subset of the supported host value.
Although no past commit explicitly enabled nested support for WAITPKG,
doing so is safe and functionally correct from an architectural
perspective as no additional KVM support is needed to virtualize TPAUSE,
UMONITOR, and UMWAIT for L2 relative to L1, and KVM already forwards
VM-Exits to L1 as necessary (commit bf653b78f960, "KVM: vmx: Introduce
handle_unexpected_vmexit and handle WAITPKG vmexit").
Note, KVM always keeps the hosts MSR_IA32_UMWAIT_CONTROL resident in
hardware, i.e. always runs both L1 and L2 with the host's power management
settings for TPAUSE and UMWAIT. See commit bf09fb6cba4f ("KVM: VMX: Stop
context switching MSR_IA32_UMWAIT_CONTROL") for more details.
Fixes: e69e72faa3a0 ("KVM: x86: Add support for user wait instructions") Cc: stable@vger.kernel.org Reported-by: Aaron Lewis <aaronlewis@google.com> Reported-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20221213062306.667649-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
projects / linux-stable / log