In the IOMMU Shared Virtual Addressing (SVA) context, the IOMMU hardware
shares and walks the CPU's page tables. The x86 architecture maps the
kernel's virtual address space into the upper portion of every process's
page table. Consequently, in an SVA context, the IOMMU hardware can walk
and cache kernel page table entries.
The Linux kernel currently lacks a notification mechanism for kernel page
table changes, specifically when page table pages are freed and reused.
The IOMMU driver is only notified of changes to user virtual address
mappings. This can cause the IOMMU's internal caches to retain stale
entries for kernel VA.
A Use-After-Free (UAF) and Write-After-Free (WAF) condition arises when
kernel page table pages are freed and later reallocated. The IOMMU could
misinterpret the new data as valid page table entries. The IOMMU might
then walk into attacker-controlled memory, leading to arbitrary physical
memory DMA access or privilege escalation. This is also a Write-After-Free
issue, as the IOMMU will potentially continue to write Accessed and Dirty
bits to the freed memory while attempting to walk the stale page tables.
Currently, SVA contexts are unprivileged and cannot access kernel
mappings. However, the IOMMU will still walk kernel-only page tables
all the way down to the leaf entries, where it realizes the mapping
is for the kernel and errors out. This means the IOMMU still caches
these intermediate page table entries, making the described vulnerability
a real concern.
To mitigate this, a new IOMMU interface is introduced to flush IOTLB
entries for the kernel address space. This interface is invoked from the
x86 architecture code that manages combined user and kernel page tables,
specifically before any kernel page table page is freed and reused.
This addresses the main issue with vfree() which is a common occurrence
and can be triggered by unprivileged users. While this resolves the
primary problem, it doesn't address some extremely rare case related to
memory unplug of memory that was present as reserved memory at boot,
which cannot be triggered by unprivileged users. The discussion can be
found at the link below.
Fixes: 26b25a2b98e4 ("iommu: Bind process address spaces to devices")
Cc: stable(a)vger.kernel.org
Suggested-by: Jann Horn <jannh(a)google.com>
Co-developed-by: Jason Gunthorpe <jgg(a)nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg(a)nvidia.com>
Signed-off-by: Lu Baolu <baolu.lu(a)linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg(a)nvidia.com>
Reviewed-by: Vasant Hegde <vasant.hegde(a)amd.com>
Reviewed-by: Kevin Tian <kevin.tian(a)intel.com>
Link: https://lore.kernel.org/linux-iommu/04983c62-3b1d-40d4-93ae-34ca04b827e5@in…
---
drivers/iommu/iommu-sva.c | 29 ++++++++++++++++++++++++++++-
include/linux/iommu.h | 4 ++++
mm/pgtable-generic.c | 2 ++
3 files changed, 34 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
index 1a51cfd82808..d236aef80a8d 100644
--- a/drivers/iommu/iommu-sva.c
+++ b/drivers/iommu/iommu-sva.c
@@ -10,6 +10,8 @@
#include "iommu-priv.h"
static DEFINE_MUTEX(iommu_sva_lock);
+static bool iommu_sva_present;
+static LIST_HEAD(iommu_sva_mms);
static struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,
struct mm_struct *mm);
@@ -42,6 +44,7 @@ static struct iommu_mm_data *iommu_alloc_mm_data(struct mm_struct *mm, struct de
return ERR_PTR(-ENOSPC);
}
iommu_mm->pasid = pasid;
+ iommu_mm->mm = mm;
INIT_LIST_HEAD(&iommu_mm->sva_domains);
/*
* Make sure the write to mm->iommu_mm is not reordered in front of
@@ -132,8 +135,13 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm
if (ret)
goto out_free_domain;
domain->users = 1;
- list_add(&domain->next, &mm->iommu_mm->sva_domains);
+ if (list_empty(&iommu_mm->sva_domains)) {
+ if (list_empty(&iommu_sva_mms))
+ iommu_sva_present = true;
+ list_add(&iommu_mm->mm_list_elm, &iommu_sva_mms);
+ }
+ list_add(&domain->next, &iommu_mm->sva_domains);
out:
refcount_set(&handle->users, 1);
mutex_unlock(&iommu_sva_lock);
@@ -175,6 +183,13 @@ void iommu_sva_unbind_device(struct iommu_sva *handle)
list_del(&domain->next);
iommu_domain_free(domain);
}
+
+ if (list_empty(&iommu_mm->sva_domains)) {
+ list_del(&iommu_mm->mm_list_elm);
+ if (list_empty(&iommu_sva_mms))
+ iommu_sva_present = false;
+ }
+
mutex_unlock(&iommu_sva_lock);
kfree(handle);
}
@@ -312,3 +327,15 @@ static struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,
return domain;
}
+
+void iommu_sva_invalidate_kva_range(unsigned long start, unsigned long end)
+{
+ struct iommu_mm_data *iommu_mm;
+
+ guard(mutex)(&iommu_sva_lock);
+ if (!iommu_sva_present)
+ return;
+
+ list_for_each_entry(iommu_mm, &iommu_sva_mms, mm_list_elm)
+ mmu_notifier_arch_invalidate_secondary_tlbs(iommu_mm->mm, start, end);
+}
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index c30d12e16473..66e4abb2df0d 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -1134,7 +1134,9 @@ struct iommu_sva {
struct iommu_mm_data {
u32 pasid;
+ struct mm_struct *mm;
struct list_head sva_domains;
+ struct list_head mm_list_elm;
};
int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode);
@@ -1615,6 +1617,7 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev,
struct mm_struct *mm);
void iommu_sva_unbind_device(struct iommu_sva *handle);
u32 iommu_sva_get_pasid(struct iommu_sva *handle);
+void iommu_sva_invalidate_kva_range(unsigned long start, unsigned long end);
#else
static inline struct iommu_sva *
iommu_sva_bind_device(struct device *dev, struct mm_struct *mm)
@@ -1639,6 +1642,7 @@ static inline u32 mm_get_enqcmd_pasid(struct mm_struct *mm)
}
static inline void mm_pasid_drop(struct mm_struct *mm) {}
+static inline void iommu_sva_invalidate_kva_range(unsigned long start, unsigned long end) {}
#endif /* CONFIG_IOMMU_SVA */
#ifdef CONFIG_IOMMU_IOPF
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 0279399d4910..2717dc9afff0 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -13,6 +13,7 @@
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/mm_inline.h>
+#include <linux/iommu.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
@@ -430,6 +431,7 @@ static void kernel_pgtable_work_func(struct work_struct *work)
list_splice_tail_init(&kernel_pgtable_work.list, &page_list);
spin_unlock(&kernel_pgtable_work.lock);
+ iommu_sva_invalidate_kva_range(PAGE_OFFSET, TLB_FLUSH_ALL);
list_for_each_entry_safe(pt, next, &page_list, pt_list)
__pagetable_free(pt);
}
--
2.43.0
Hi Stable,
Please provide a quote for your products:
Include:
1.Pricing (per unit)
2.Delivery cost & timeline
3.Quote expiry date
Deadline: September
Thanks!
Kamal Prasad
Albinayah Trading
When do_task() exhausts its RXE_MAX_ITERATIONS budget, it unconditionally
sets the task state to TASK_STATE_IDLE to reschedule. This overwrites
the TASK_STATE_DRAINING state that may have been concurrently set by
rxe_cleanup_task() or rxe_disable_task().
This race condition breaks the cleanup and disable logic, which expects
the task to stop processing new work. The cleanup code may proceed while
do_task() reschedules itself, leading to a potential use-after-free.
This bug was introduced during the migration from tasklets to workqueues,
where the special handling for the draining case was lost.
Fix this by restoring the original behavior. If the state is
TASK_STATE_DRAINING when iterations are exhausted, continue the loop by
setting cont to 1. This allows new iterations to finish the remaining
work and reach the switch statement, which properly transitions the
state to TASK_STATE_DRAINED and stops the task as intended.
Fixes: 9b4b7c1f9f54 ("RDMA/rxe: Add workqueue support for rxe tasks")
Cc: stable(a)vger.kernel.org
Signed-off-by: Gui-Dong Han <hanguidong02(a)gmail.com>
---
drivers/infiniband/sw/rxe/rxe_task.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_task.c b/drivers/infiniband/sw/rxe/rxe_task.c
index 6f8f353e9583..f522820b950c 100644
--- a/drivers/infiniband/sw/rxe/rxe_task.c
+++ b/drivers/infiniband/sw/rxe/rxe_task.c
@@ -132,8 +132,12 @@ static void do_task(struct rxe_task *task)
* yield the cpu and reschedule the task
*/
if (!ret) {
- task->state = TASK_STATE_IDLE;
- resched = 1;
+ if (task->state != TASK_STATE_DRAINING) {
+ task->state = TASK_STATE_IDLE;
+ resched = 1;
+ } else {
+ cont = 1;
+ }
goto exit;
}
--
2.25.1
An untrusted device may return a NULL context pointer in the request
header. hptiop_iop_request_callback_itl() dereferences that pointer
unconditionally to write result fields and to invoke arg->done(), which
can cause a NULL pointer dereference.
Add a NULL check for the reconstructed context pointer. If it is NULL,
acknowledge the request by writing the tag to the outbound queue and
return early.
Fixes: ede1e6f8b432 ("[SCSI] hptiop: HighPoint RocketRAID 3xxx controller driver")
Cc: stable(a)vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244(a)gmail.com>
---
drivers/scsi/hptiop.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/scsi/hptiop.c b/drivers/scsi/hptiop.c
index 21f1d9871a33..2b29cd83ce5e 100644
--- a/drivers/scsi/hptiop.c
+++ b/drivers/scsi/hptiop.c
@@ -812,6 +812,11 @@ static void hptiop_iop_request_callback_itl(struct hptiop_hba *hba, u32 tag)
(readl(&req->context) |
((u64)readl(&req->context_hi32)<<32));
+ if (!arg) {
+ writel(tag, &hba->u.itl.iop->outbound_queue);
+ return;
+ }
+
if (readl(&req->result) == IOP_RESULT_SUCCESS) {
arg->result = HPT_IOCTL_RESULT_OK;
--
2.43.0
If ab->fw.m3_data points to data, then fw pointer remains null.
Further, if m3_mem is not allocated, then fw is dereferenced to be
passed to ath11k_err function.
Replace fw->size by m3_len.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 7db88b962f06 ("wifi: ath11k: add firmware-2.bin support")
Cc: stable(a)vger.kernel.org
Signed-off-by: Matvey Kovalev <matvey.kovalev(a)ispras.ru>
---
drivers/net/wireless/ath/ath11k/qmi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath11k/qmi.c b/drivers/net/wireless/ath/ath11k/qmi.c
index 378ac96b861b7..1a42b4abe7168 100644
--- a/drivers/net/wireless/ath/ath11k/qmi.c
+++ b/drivers/net/wireless/ath/ath11k/qmi.c
@@ -2557,7 +2557,7 @@ static int ath11k_qmi_m3_load(struct ath11k_base *ab)
GFP_KERNEL);
if (!m3_mem->vaddr) {
ath11k_err(ab, "failed to allocate memory for M3 with size %zu\n",
- fw->size);
+ m3_len);
ret = -ENOMEM;
goto out;
}
--
2.43.0.windows.1