From: Sean Christopherson <seanjc(a)google.com>
[ Upstream commit 4b7c3f6d04bd53f2e5b228b6821fb8f5d1ba3071 ]
Ignore the userspace provided x2APIC ID when fixing up APIC state for
KVM_SET_LAPIC, i.e. make the x2APIC fully readonly in KVM. Commit
a92e2543d6a8 ("KVM: x86: use hardware-compatible format for APIC ID
register"), which added the fixup, didn't intend to allow userspace to
modify the x2APIC ID. In fact, that commit is when KVM first started
treating the x2APIC ID as readonly, apparently to fix some race:
static inline u32 kvm_apic_id(struct kvm_lapic *apic)
{
- return (kvm_lapic_get_reg(apic, APIC_ID) >> 24) & 0xff;
+ /* To avoid a race between apic_base and following APIC_ID update when
+ * switching to x2apic_mode, the x2apic mode returns initial x2apic id.
+ */
+ if (apic_x2apic_mode(apic))
+ return apic->vcpu->vcpu_id;
+
+ return kvm_lapic_get_reg(apic, APIC_ID) >> 24;
}
Furthermore, KVM doesn't support delivering interrupts to vCPUs with a
modified x2APIC ID, but KVM *does* return the modified value on a guest
RDMSR and for KVM_GET_LAPIC. I.e. no remotely sane setup can actually
work with a modified x2APIC ID.
Making the x2APIC ID fully readonly fixes a WARN in KVM's optimized map
calculation, which expects the LDR to align with the x2APIC ID.
WARNING: CPU: 2 PID: 958 at arch/x86/kvm/lapic.c:331 kvm_recalculate_apic_map+0x609/0xa00 [kvm]
CPU: 2 PID: 958 Comm: recalc_apic_map Not tainted 6.4.0-rc3-vanilla+ #35
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.2-1-1 04/01/2014
RIP: 0010:kvm_recalculate_apic_map+0x609/0xa00 [kvm]
Call Trace:
<TASK>
kvm_apic_set_state+0x1cf/0x5b0 [kvm]
kvm_arch_vcpu_ioctl+0x1806/0x2100 [kvm]
kvm_vcpu_ioctl+0x663/0x8a0 [kvm]
__x64_sys_ioctl+0xb8/0xf0
do_syscall_64+0x56/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7fade8b9dd6f
Unfortunately, the WARN can still trigger for other CPUs than the current
one by racing against KVM_SET_LAPIC, so remove it completely.
Reported-by: Michal Luczaj <mhal(a)rbox.co>
Closes: https://lore.kernel.org/all/814baa0c-1eaa-4503-129f-059917365e80@rbox.co
Reported-by: Haoyu Wu <haoyuwu254(a)gmail.com>
Closes: https://lore.kernel.org/all/20240126161633.62529-1-haoyuwu254@gmail.com
Reported-by: syzbot+545f1326f405db4e1c3e(a)syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000c2a6b9061cbca3c3@google.com
Signed-off-by: Sean Christopherson <seanjc(a)google.com>
Message-ID: <20240802202941.344889-2-seanjc(a)google.com>
Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com>
Signed-off-by: Gavin Guo <gavinguo(a)igalia.com>
---
arch/x86/kvm/lapic.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 34766abbabd8..cd9c1e1f6fd3 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -338,10 +338,8 @@ static void kvm_recalculate_logical_map(struct kvm_apic_map *new,
* reversing the LDR calculation to get cluster of APICs, i.e. no
* additional work is required.
*/
- if (apic_x2apic_mode(apic)) {
- WARN_ON_ONCE(ldr != kvm_apic_calc_x2apic_ldr(kvm_x2apic_id(apic)));
+ if (apic_x2apic_mode(apic))
return;
- }
if (WARN_ON_ONCE(!kvm_apic_map_get_logical_dest(new, ldr,
&cluster, &mask))) {
@@ -2964,18 +2962,28 @@ static int kvm_apic_state_fixup(struct kvm_vcpu *vcpu,
struct kvm_lapic_state *s, bool set)
{
if (apic_x2apic_mode(vcpu->arch.apic)) {
+ u32 x2apic_id = kvm_x2apic_id(vcpu->arch.apic);
u32 *id = (u32 *)(s->regs + APIC_ID);
u32 *ldr = (u32 *)(s->regs + APIC_LDR);
u64 icr;
if (vcpu->kvm->arch.x2apic_format) {
- if (*id != vcpu->vcpu_id)
+ if (*id != x2apic_id)
return -EINVAL;
} else {
+ /*
+ * Ignore the userspace value when setting APIC state.
+ * KVM's model is that the x2APIC ID is readonly, e.g.
+ * KVM only supports delivering interrupts to KVM's
+ * version of the x2APIC ID. However, for backwards
+ * compatibility, don't reject attempts to set a
+ * mismatched ID for userspace that hasn't opted into
+ * x2apic_format.
+ */
if (set)
- *id >>= 24;
+ *id = x2apic_id;
else
- *id <<= 24;
+ *id = x2apic_id << 24;
}
/*
@@ -2984,7 +2992,7 @@ static int kvm_apic_state_fixup(struct kvm_vcpu *vcpu,
* split to ICR+ICR2 in userspace for backwards compatibility.
*/
if (set) {
- *ldr = kvm_apic_calc_x2apic_ldr(*id);
+ *ldr = kvm_apic_calc_x2apic_ldr(x2apic_id);
icr = __kvm_lapic_get_reg(s->regs, APIC_ICR) |
(u64)__kvm_lapic_get_reg(s->regs, APIC_ICR2) << 32;
--
2.43.0
I am using an Acer Aspire A115-31 laptop. When running newer kernel
versions, sound played through headphones is distorted, but when running
older versions, it is not.
Kernel version: Linux version 6.12.5 (user@hostname) (gcc (Debian
14.2.0-8) 14.2.0, GNU ld (GNU Binutils for Debian) 2.43.50.20241210) #1
SMP PREEMPT_DYNAMIC Sun Dec 15 05:09:16 IST 2024
Operating System: Debian GNU/Linux trixie/sid
No special actions are needed to reproduce the issue. The sound is
distorted all the time, and it doesn't depend on anything besides using
an affected kernel version.
It seems to be caused by commit 34ab5bbc6e82214d7f7393eba26d164b303ebb4e
(ALSA: hda/realtek - Add Headset Mic supported Acer NB platform).
Indeed, if I remove the entry that this commit adds, the issue disappears.
lspci output for the device in question:
00:0e.0 Multimedia audio controller [0401]: Intel Corporation
Celeron/Pentium Silver Processor High Definition Audio [8086:3198] (rev 06)
Subsystem: Acer Incorporated [ALI] Device [1025:1360]
Flags: bus master, fast devsel, latency 0, IRQ 130
Memory at a1214000 (64-bit, non-prefetchable) [size=16K]
Memory at a1000000 (64-bit, non-prefetchable) [size=1M]
Capabilities: [50] Power Management version 3
Capabilities: [80] Vendor Specific Information: Len=14 <?>
Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit+
Capabilities: [70] Express Root Complex Integrated Endpoint,
IntMsgNum 0
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel, snd_soc_avs, snd_sof_pci_intel_apl
From: Roberto Sassu <roberto.sassu(a)huawei.com>
Commit 11c60f23ed13 ("integrity: Remove unused macro
IMA_ACTION_RULE_FLAGS") removed the IMA_ACTION_RULE_FLAGS mask, due to it
not being used after commit 0d73a55208e9 ("ima: re-introduce own integrity
cache lock").
However, it seems that the latter commit mistakenly used the wrong mask
when moving the code from ima_inode_post_setattr() to
process_measurement(). There is no mention in the commit message about this
change and it looks quite important, since changing from IMA_ACTIONS_FLAGS
(later renamed to IMA_NONACTION_FLAGS) to IMA_ACTION_RULE_FLAGS was done by
commit 42a4c603198f0 ("ima: fix ima_inode_post_setattr").
Restore the original change, but with new mask 0xfb000000 since the
policy-specific flags changed meanwhile, and rename IMA_ACTION_RULE_FLAGS
to IMA_NONACTION_RULE_FLAGS, to be consistent with IMA_NONACTION_FLAGS.
Cc: stable(a)vger.kernel.org # v4.16.x
Fixes: 11c60f23ed13 ("integrity: Remove unused macro IMA_ACTION_RULE_FLAGS")
Signed-off-by: Roberto Sassu <roberto.sassu(a)huawei.com>
---
security/integrity/ima/ima.h | 1 +
security/integrity/ima/ima_main.c | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 22c3b87cfcac..32ffef2cc92a 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -141,6 +141,7 @@ struct ima_kexec_hdr {
/* IMA iint policy rule cache flags */
#define IMA_NONACTION_FLAGS 0xff000000
+#define IMA_NONACTION_RULE_FLAGS 0xfb000000
#define IMA_DIGSIG_REQUIRED 0x01000000
#define IMA_PERMIT_DIRECTIO 0x02000000
#define IMA_NEW_FILE 0x04000000
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 712c3a522e6c..83e467ad18d4 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -277,7 +277,7 @@ static int process_measurement(struct file *file, const struct cred *cred,
/* reset appraisal flags if ima_inode_post_setattr was called */
iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
- IMA_NONACTION_FLAGS);
+ IMA_NONACTION_RULE_FLAGS);
/*
* Re-evaulate the file if either the xattr has changed or the
--
2.47.0.118.gfd3785337b
The following call-chain leads to misuse of spinlock_irq
when spinlock_irqsave was hold.
irq_set_vcpu_affinity
-> irq_get_desc_lock (spinlock_irqsave)
-> its_irq_set_vcpu_affinity
-> guard(raw_spin_lock_irq) <--- this enables interrupts
-> irq_put_desc_unlock // <--- WARN IRQs enabled
Fix the issue by using guard(raw_spinlock), since the function is
already called with irqsave and raw_spin_lock was used before the commit
b97e8a2f7130 ("irqchip/gic-v3-its: Fix potential race condition in its_vlpi_prop_update()")
introducing the guard as well.
This was discovered through the lock debugging, and the corresponding
log is as follows:
raw_local_irq_restore() called with IRQs enabled
WARNING: CPU: 38 PID: 444 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x2c/0x38
Call trace:
warn_bogus_irq_restore+0x2c/0x38
_raw_spin_unlock_irqrestore+0x68/0x88
__irq_put_desc_unlock+0x1c/0x48
irq_set_vcpu_affinity+0x74/0xc0
its_map_vlpi+0x44/0x88
kvm_vgic_v4_set_forwarding+0x148/0x230
kvm_arch_irq_bypass_add_producer+0x20/0x28
__connect+0x98/0xb8
irq_bypass_register_consumer+0x150/0x178
kvm_irqfd+0x6dc/0x744
kvm_vm_ioctl+0xe44/0x16b0
Fixes: b97e8a2f7130 ("irqchip/gic-v3-its: Fix potential race condition in its_vlpi_prop_update()")
Signed-off-by: Tomas Krcka <krckatom(a)amazon.de>
Reviewed-by: Marc Zyngier <maz(a)kernel.org>
Cc: stable(a)vger.kernel.org
---
drivers/irqchip/irq-gic-v3-its.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 92244cfa0464..8c3ec5734f1e 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2045,7 +2045,7 @@ static int its_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
if (!is_v4(its_dev->its))
return -EINVAL;
- guard(raw_spinlock_irq)(&its_dev->event_map.vlpi_lock);
+ guard(raw_spinlock)(&its_dev->event_map.vlpi_lock);
/* Unmap request? */
if (!info)
--
2.40.1
Amazon Web Services Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B
Sitz: Berlin
Ust-ID: DE 365 538 597
There is a data race between the functions driver_override_show() and
driver_override_store(). In the driver_override_store() function, the
assignment to ret calls driver_set_override(), which frees the old value
while writing the new value to dev. If a race occurs, it may cause a
use-after-free (UAF) error in driver_override_show().
To fix this issue, we adopt a logic similar to the driver_override_show()
function in vmbus_drv.c, protecting dev within a lock to ensure its value
remains unchanged.
This possible bug is found by an experimental static analysis tool
developed by our team. This tool analyzes the locking APIs to extract
function pairs that can be concurrently executed, and then analyzes the
instructions in the paired functions to identify possible concurrency bugs
including data races and atomicity violations.
Fixes: 48a6c7bced2a ("cdx: add device attributes")
Cc: stable(a)vger.kernel.org
Signed-off-by: Qiu-ji Chen <chenqiuji666(a)gmail.com>
---
V2:
Modified the title and description.
Removed the changes to cdx_bus_match().
---
drivers/cdx/cdx.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/cdx/cdx.c b/drivers/cdx/cdx.c
index 07371cb653d3..4af1901c9d52 100644
--- a/drivers/cdx/cdx.c
+++ b/drivers/cdx/cdx.c
@@ -470,8 +470,12 @@ static ssize_t driver_override_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct cdx_device *cdx_dev = to_cdx_device(dev);
+ ssize_t len;
- return sysfs_emit(buf, "%s\n", cdx_dev->driver_override);
+ device_lock(dev);
+ len = sysfs_emit(buf, "%s\n", cdx_dev->driver_override);
+ device_unlock(dev);
+ return len;
}
static DEVICE_ATTR_RW(driver_override);
--
2.34.1
From: Cheng Ming Lin <chengminglin(a)mxic.com.tw>
The default dummy cycle for Macronix SPI NOR flash in Octal Output
Read Mode(1-1-8) is 20.
Currently, the dummy buswidth is set according to the address bus width.
In the 1-1-8 mode, this means the dummy buswidth is 1. When converting
dummy cycles to bytes, this results in 20 x 1 / 8 = 2 bytes, causing the
host to read data 4 cycles too early.
Since the protocol data buswidth is always greater than or equal to the
address buswidth. Setting the dummy buswidth to match the data buswidth
increases the likelihood that the dummy cycle-to-byte conversion will be
divisible, preventing the host from reading data prematurely.
Fixes: 0e30f47232ab5 ("mtd: spi-nor: add support for DTR protocol")
Cc: stable(a)vger.kernel.org
Reviewd-by: Pratyush Yadav <pratyush(a)kernel.org>
Signed-off-by: Cheng Ming Lin <chengminglin(a)mxic.com.tw>
---
drivers/mtd/spi-nor/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index f9c189ed7353..c7aceaa8a43f 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -89,7 +89,7 @@ void spi_nor_spimem_setup_op(const struct spi_nor *nor,
op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
if (op->dummy.nbytes)
- op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
+ op->dummy.buswidth = spi_nor_get_protocol_data_nbits(proto);
if (op->data.nbytes)
op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
--
2.25.1