The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com --- drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size) - __field(u32, new_placement) - __field(u32, old_placement) + __string(new_placement_name, xe_mem_type_to_name[new_placement]) + __string(old_placement_name, xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ), @@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size; - __entry->new_placement = new_placement; - __entry->old_placement = old_placement; + __assign_str(new_placement_name); + __assign_str(old_placement_name); __assign_str(device_id); __entry->move_lacks_source = move_lacks_source; ), TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s", __entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size, - xe_mem_type_to_name[__entry->old_placement], - xe_mem_type_to_name[__entry->new_placement], __get_str(device_id)) + __get_str(old_placement_name), + __get_str(new_placement_name), __get_str(device_id)) );
DECLARE_EVENT_CLASS(xe_vma,
On Mon, Dec 23, 2024 at 02:42:50PM +0100, Thomas Hellström wrote:
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name, xe_mem_type_to_name[new_placement])__string(old_placement_name, xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ),@@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);
xe_mem_type_to_name[__entry->old_placement],xe_mem_type_to_name[__entry->new_placement], __get_str(device_id))
So is this the UAF? i.e., The Xe module unloads and xe_mem_type_to_name is gone?
I noticed that xe_mem_type_to_name is not static, it likely should be. Would that help here?
Matt
__get_str(old_placement_name),__get_str(new_placement_name), __get_str(device_id))); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
On Mon, 2024-12-23 at 07:44 -0800, Matthew Brost wrote:
On Mon, Dec 23, 2024 at 02:42:50PM +0100, Thomas Hellström wrote:
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name,xe_mem_type_to_name[new_placement])
__string(old_placement_name,xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ), @@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);__assign_str(device_id); __entry->move_lacks_source = move_lacks_source; ), TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s", __entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size,
xe_mem_type_to_name[__entry->old_placement],xe_mem_type_to_name[__entry->new_placement],__get_str(device_id))
So is this the UAF? i.e., The Xe module unloads and xe_mem_type_to_name is gone?
I would imagine that's the intention of the warning. However removing the xe_module seems to empty the trace buffer of xe_bo_move events. Whether there is a race in that process or whether the TP_printk check can't distinguish between module local addresses and other addresses is hard to tell. In any case, it looks like we need to comply with the warning here (I suspect CI refuses to run otherwise), and since it only appears to trigger on the xe module load on my system, it's unlikely that mentioned commit will be reverted.
I noticed that xe_mem_type_to_name is not static, it likely should be. Would that help here?
No, doesn't help unfortunately.
/Thomas
Matt
__get_str(old_placement_name),__get_str(new_placement_name),__get_str(device_id)) ); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
On Mon, Dec 23, 2024 at 05:33:10PM +0100, Thomas Hellström wrote:
On Mon, 2024-12-23 at 07:44 -0800, Matthew Brost wrote:
On Mon, Dec 23, 2024 at 02:42:50PM +0100, Thomas Hellström wrote:
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name,xe_mem_type_to_name[new_placement])
__string(old_placement_name,xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ), @@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);__assign_str(device_id); __entry->move_lacks_source = move_lacks_source; ), TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s", __entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size,
xe_mem_type_to_name[__entry->old_placement],xe_mem_type_to_name[__entry->new_placement],__get_str(device_id))
So is this the UAF? i.e., The Xe module unloads and xe_mem_type_to_name is gone?
I would imagine that's the intention of the warning. However removing the xe_module seems to empty the trace buffer of xe_bo_move events. Whether there is a race in that process or whether the TP_printk check can't distinguish between module local addresses and other addresses is hard to tell. In any case, it looks like we need to comply with the warning here (I suspect CI refuses to run otherwise), and since it only appears to trigger on the xe module load on my system, it's unlikely that mentioned commit will be reverted.
it's actually a false positive from afd2627f727b. See explanation by Steve at https://lore.kernel.org/all/20241230141329.5f698715@batman.local.home/ the fix later on
Lucas De Marchi
I noticed that xe_mem_type_to_name is not static, it likely should be. Would that help here?
No, doesn't help unfortunately.
/Thomas
Matt
__get_str(old_placement_name),__get_str(new_placement_name),__get_str(device_id)) ); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
-----Original Message----- From: Intel-xe intel-xe-bounces@lists.freedesktop.org On Behalf Of Thomas Hellström Sent: Monday, December 23, 2024 5:43 AM To: intel-xe@lists.freedesktop.org Cc: Thomas Hellström thomas.hellstrom@linux.intel.com; Sousa, Gustavo gustavo.sousa@intel.com; De Marchi, Lucas lucas.demarchi@intel.com; Radhakrishna Sripada radhakrishna.sripada@intel.com; Roper, Matthew D matthew.d.roper@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com; stable@vger.kernel.org Subject: [PATCH] drm/xe/tracing: Fix a potential TP_printk UAF
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
I take it we're hitting the WARN_ONCE in ignore_event due to a test_safe_str failure?
I don't know about us hitting a UAF here, but this fix is exactly what was recommended in the comment immediately above the WARN_ONCE that we shouldn't be hitting, so this is probably correct if that's what we're trying to avoid. Reviewed-by: Jonathan Cavitt jonathan.cavitt@intel.com -Jonathan Cavitt
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name, xe_mem_type_to_name[new_placement])__string(old_placement_name, xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ),@@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);
xe_mem_type_to_name[__entry->old_placement],xe_mem_type_to_name[__entry->new_placement], __get_str(device_id))
__get_str(old_placement_name),__get_str(new_placement_name), __get_str(device_id))); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
On Mon, 2024-12-23 at 15:44 +0000, Cavitt, Jonathan wrote:
-----Original Message----- From: Intel-xe intel-xe-bounces@lists.freedesktop.org On Behalf Of Thomas Hellström Sent: Monday, December 23, 2024 5:43 AM To: intel-xe@lists.freedesktop.org Cc: Thomas Hellström thomas.hellstrom@linux.intel.com; Sousa, Gustavo gustavo.sousa@intel.com; De Marchi, Lucas lucas.demarchi@intel.com; Radhakrishna Sripada radhakrishna.sripada@intel.com; Roper, Matthew D matthew.d.roper@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com; stable@vger.kernel.org Subject: [PATCH] drm/xe/tracing: Fix a potential TP_printk UAF
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
I take it we're hitting the WARN_ONCE in ignore_event due to a test_safe_str failure?
Actually it's the WARN_ONCE in test_event_printk()
if (WARN_ON_ONCE(dereference_flags)) {
I don't know about us hitting a UAF here, but this fix is exactly what was recommended in the comment immediately above the WARN_ONCE that we shouldn't be hitting, so this is probably correct if that's what we're trying to avoid.
I'll double-check to see if I can easily trigger the UAF.
Reviewed-by: Jonathan Cavitt jonathan.cavitt@intel.com
Thanks, Thomas
-Jonathan Cavitt
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name,xe_mem_type_to_name[new_placement])
__string(old_placement_name,xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ), @@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);__assign_str(device_id); __entry->move_lacks_source = move_lacks_source; ), TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s", __entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size,
xe_mem_type_to_name[__entry->old_placement],xe_mem_type_to_name[__entry->new_placement],__get_str(device_id))
__get_str(old_placement_name),__get_str(new_placement_name),__get_str(device_id)) ); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
-----Original Message----- From: Thomas Hellström thomas.hellstrom@linux.intel.com Sent: Monday, December 23, 2024 7:57 AM To: Cavitt, Jonathan jonathan.cavitt@intel.com; intel-xe@lists.freedesktop.org Cc: Sousa, Gustavo gustavo.sousa@intel.com; De Marchi, Lucas lucas.demarchi@intel.com; Radhakrishna Sripada radhakrishna.sripada@intel.com; Roper, Matthew D matthew.d.roper@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com; stable@vger.kernel.org Subject: Re: [PATCH] drm/xe/tracing: Fix a potential TP_printk UAF
On Mon, 2024-12-23 at 15:44 +0000, Cavitt, Jonathan wrote:
-----Original Message----- From: Intel-xe intel-xe-bounces@lists.freedesktop.org On Behalf Of Thomas Hellström Sent: Monday, December 23, 2024 5:43 AM To: intel-xe@lists.freedesktop.org Cc: Thomas Hellström thomas.hellstrom@linux.intel.com; Sousa, Gustavo gustavo.sousa@intel.com; De Marchi, Lucas lucas.demarchi@intel.com; Radhakrishna Sripada radhakrishna.sripada@intel.com; Roper, Matthew D matthew.d.roper@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com; stable@vger.kernel.org Subject: [PATCH] drm/xe/tracing: Fix a potential TP_printk UAF
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
I take it we're hitting the WARN_ONCE in ignore_event due to a test_safe_str failure?
Actually it's the WARN_ONCE in test_event_printk()
if (WARN_ON_ONCE(dereference_flags)) {
Ah, I see.
There's a comment above that WARN_ON_ONCE as well, and it more or less recommends the same actions, albeit with less specificity. My RB still stands. -Jonathan Cavitt
I don't know about us hitting a UAF here, but this fix is exactly what was recommended in the comment immediately above the WARN_ONCE that we shouldn't be hitting, so this is probably correct if that's what we're trying to avoid.
I'll double-check to see if I can easily trigger the UAF.
Reviewed-by: Jonathan Cavitt jonathan.cavitt@intel.com
Thanks, Thomas
-Jonathan Cavitt
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name,xe_mem_type_to_name[new_placement])
__string(old_placement_name,xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ), @@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);__assign_str(device_id); __entry->move_lacks_source = move_lacks_source; ), TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s", __entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size,
xe_mem_type_to_name[__entry->old_placement],xe_mem_type_to_name[__entry->new_placement],__get_str(device_id))
__get_str(old_placement_name),__get_str(new_placement_name),__get_str(device_id)) ); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
On Mon, 2024-12-23 at 17:04 +0000, Cavitt, Jonathan wrote:
-----Original Message----- From: Thomas Hellström thomas.hellstrom@linux.intel.com Sent: Monday, December 23, 2024 7:57 AM To: Cavitt, Jonathan jonathan.cavitt@intel.com; intel-xe@lists.freedesktop.org Cc: Sousa, Gustavo gustavo.sousa@intel.com; De Marchi, Lucas lucas.demarchi@intel.com; Radhakrishna Sripada radhakrishna.sripada@intel.com; Roper, Matthew D matthew.d.roper@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com; stable@vger.kernel.org Subject: Re: [PATCH] drm/xe/tracing: Fix a potential TP_printk UAF
On Mon, 2024-12-23 at 15:44 +0000, Cavitt, Jonathan wrote:
-----Original Message----- From: Intel-xe intel-xe-bounces@lists.freedesktop.org On Behalf Of Thomas Hellström Sent: Monday, December 23, 2024 5:43 AM To: intel-xe@lists.freedesktop.org Cc: Thomas Hellström thomas.hellstrom@linux.intel.com; Sousa, Gustavo gustavo.sousa@intel.com; De Marchi, Lucas lucas.demarchi@intel.com; Radhakrishna Sripada radhakrishna.sripada@intel.com; Roper, Matthew D matthew.d.roper@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com; stable@vger.kernel.org Subject: [PATCH] drm/xe/tracing: Fix a potential TP_printk UAF
The commit afd2627f727b ("tracing: Check "%s" dereference via the field and not the TP_printk format") exposes potential UAFs in the xe_bo_move trace event.
Fix those by avoiding dereferencing the xe_mem_type_to_name[] array at TP_printk time.
Since some code refactoring has taken place, explicit backporting may be needed for kernels older than 6.10.
Fixes: e46d3f813abd ("drm/xe/trace: Extract bo, vm, vma traces") Cc: Gustavo Sousa gustavo.sousa@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Cc: Radhakrishna Sripada radhakrishna.sripada@intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: "Thomas Hellström" thomas.hellstrom@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: intel-xe@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com
I take it we're hitting the WARN_ONCE in ignore_event due to a test_safe_str failure?
Actually it's the WARN_ONCE in test_event_printk()
if (WARN_ON_ONCE(dereference_flags)) {
Ah, I see.
There's a comment above that WARN_ON_ONCE as well, and it more or less recommends the same actions, albeit with less specificity. My RB still stands.
Thanks. I'll push this commit with that R-B to get CI running.
/Thomas
-Jonathan Cavitt
I don't know about us hitting a UAF here, but this fix is exactly what was recommended in the comment immediately above the WARN_ONCE that we shouldn't be hitting, so this is probably correct if that's what we're trying to avoid.
I'll double-check to see if I can easily trigger the UAF.
Reviewed-by: Jonathan Cavitt jonathan.cavitt@intel.com
Thanks, Thomas
-Jonathan Cavitt
drivers/gpu/drm/xe/xe_trace_bo.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_trace_bo.h b/drivers/gpu/drm/xe/xe_trace_bo.h index 1762dd30ba6d..ea50fee50c7d 100644 --- a/drivers/gpu/drm/xe/xe_trace_bo.h +++ b/drivers/gpu/drm/xe/xe_trace_bo.h @@ -60,8 +60,8 @@ TRACE_EVENT(xe_bo_move, TP_STRUCT__entry( __field(struct xe_bo *, bo) __field(size_t, size)
__field(u32, new_placement)__field(u32, old_placement)
__string(new_placement_name,xe_mem_type_to_name[new_placement])
__string(old_placement_name,xe_mem_type_to_name[old_placement]) __string(device_id, __dev_name_bo(bo)) __field(bool, move_lacks_source) ), @@ -69,15 +69,15 @@ TRACE_EVENT(xe_bo_move, TP_fast_assign( __entry->bo = bo; __entry->size = bo->size;
__entry->new_placement = new_placement;__entry->old_placement = old_placement;
__assign_str(new_placement_name);__assign_str(old_placement_name);__assign_str(device_id); __entry->move_lacks_source = move_lacks_source; ), TP_printk("move_lacks_source:%s, migrate object %p [size %zu] from %s to %s device_id:%s", __entry->move_lacks_source ? "yes" : "no", __entry->bo, __entry->size,
xe_mem_type_to_name[__entry-old_placement],
xe_mem_type_to_name[__entry-new_placement],
__get_str(device_id))
__get_str(old_placement_name),__get_str(new_placement_name),__get_str(device_id)) ); DECLARE_EVENT_CLASS(xe_vma, -- 2.47.1
linux-stable-mirror@lists.linaro.org
-
Cavitt, Jonathan -
Lucas De Marchi -
Matthew Brost -
Thomas Hellström