From 0ecbb45e30abd0b1e59012fa3f3d5781140248b3 Mon Sep 17 00:00:00 2001 From: Shyam Saini Date: Thu, 27 Feb 2025 10:49:27 -0800 Subject: [PATCH 1/7] kernel: param: rename locate_module_kobject [ Upstream commit bbc9462f0cb0c8917a4908e856731708f0cee910 ] The locate_module_kobject() function looks up an existing module_kobject for a given module name. If it cannot find the corresponding module_kobject, it creates one for the given name. This commit renames locate_module_kobject() to lookup_or_create_module_kobject() to better describe its operations. This doesn't change anything functionality wise. Suggested-by: Rasmus Villemoes Signed-off-by: Shyam Saini Link: https://lore.kernel.org/r/20250227184930.34163-2-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu Stable-dep-of: f95bbfe18512 ("drivers: base: handle module_kobject creation") Signed-off-by: Sasha Levin --- kernel/params.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/params.c b/kernel/params.c index 2d4a0564697e..8d48a6bfe68d 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -759,7 +759,7 @@ void destroy_params(const struct kernel_param *params, unsigned num) params[i].ops->free(params[i].arg); } -static struct module_kobject * __init locate_module_kobject(const char *name) +static struct module_kobject * __init lookup_or_create_module_kobject(const char *name) { struct module_kobject *mk; struct kobject *kobj; @@ -801,7 +801,7 @@ static void __init kernel_add_sysfs_param(const char *name, struct module_kobject *mk; int err; - mk = locate_module_kobject(name); + mk = lookup_or_create_module_kobject(name); if (!mk) return; @@ -872,7 +872,7 @@ static void __init version_sysfs_builtin(void) int err; for (vattr = __start___modver; vattr < __stop___modver; vattr++) { - mk = locate_module_kobject(vattr->module_name); + mk = lookup_or_create_module_kobject(vattr->module_name); if (mk) { err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); WARN_ON_ONCE(err); From ace531f2fea11dd56fdfa11eb948cbf689e6339e Mon Sep 17 00:00:00 2001 From: Shyam Saini Date: Thu, 27 Feb 2025 10:49:29 -0800 Subject: [PATCH 2/7] kernel: globalize lookup_or_create_module_kobject() [ Upstream commit 7c76c813cfc42a7376378a0c4b7250db2eebab81 ] lookup_or_create_module_kobject() is marked as static and __init, to make it global drop static keyword. Since this function can be called from non-init code, use __modinit instead of __init, __modinit marker will make it __init if CONFIG_MODULES is not defined. Suggested-by: Rasmus Villemoes Signed-off-by: Shyam Saini Link: https://lore.kernel.org/r/20250227184930.34163-4-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu Stable-dep-of: f95bbfe18512 ("drivers: base: handle module_kobject creation") Signed-off-by: Sasha Levin --- include/linux/module.h | 2 ++ kernel/params.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/include/linux/module.h b/include/linux/module.h index a98e188cf37b..f2a8624eef1e 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -162,6 +162,8 @@ extern void cleanup_module(void); #define __INITRODATA_OR_MODULE __INITRODATA #endif /*CONFIG_MODULES*/ +struct module_kobject *lookup_or_create_module_kobject(const char *name); + /* Generic info of form tag = "info" */ #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info) diff --git a/kernel/params.c b/kernel/params.c index 8d48a6bfe68d..c7aed3c51cd5 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -759,7 +759,7 @@ void destroy_params(const struct kernel_param *params, unsigned num) params[i].ops->free(params[i].arg); } -static struct module_kobject * __init lookup_or_create_module_kobject(const char *name) +struct module_kobject __modinit * lookup_or_create_module_kobject(const char *name) { struct module_kobject *mk; struct kobject *kobj; From 8f2451ebaf5b8adffdbdf2ee42e4adf94d213aec Mon Sep 17 00:00:00 2001 From: Shyam Saini Date: Thu, 27 Feb 2025 10:49:30 -0800 Subject: [PATCH 3/7] drivers: base: handle module_kobject creation [ Upstream commit f95bbfe18512c5c018720468959edac056a17196 ] module_add_driver() relies on module_kset list for /sys/module//drivers directory creation. Since, commit 96a1a2412acba ("kernel/params.c: defer most of param_sysfs_init() to late_initcall time") drivers which are initialized from subsys_initcall() or any other higher precedence initcall couldn't find the related kobject entry in the module_kset list because module_kset is not fully populated by the time module_add_driver() refers it. As a consequence, module_add_driver() returns early without calling make_driver_name(). Therefore, /sys/module//drivers is never created. Fix this issue by letting module_add_driver() handle module_kobject creation itself. Fixes: 96a1a2412acb ("kernel/params.c: defer most of param_sysfs_init() to late_initcall time") Cc: stable@vger.kernel.org # requires all other patches from the series Suggested-by: Rasmus Villemoes Signed-off-by: Shyam Saini Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250227184930.34163-5-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu Signed-off-by: Sasha Levin --- drivers/base/module.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/base/module.c b/drivers/base/module.c index a33663d92256..955582b34e54 100644 --- a/drivers/base/module.c +++ b/drivers/base/module.c @@ -42,16 +42,13 @@ int module_add_driver(struct module *mod, struct device_driver *drv) if (mod) mk = &mod->mkobj; else if (drv->mod_name) { - struct kobject *mkobj; - - /* Lookup built-in module entry in /sys/modules */ - mkobj = kset_find_obj(module_kset, drv->mod_name); - if (mkobj) { - mk = container_of(mkobj, struct module_kobject, kobj); + /* Lookup or create built-in module entry in /sys/modules */ + mk = lookup_or_create_module_kobject(drv->mod_name); + if (mk) { /* remember our module structure */ drv->p->mkobj = mk; - /* kset_find_obj took a reference */ - kobject_put(mkobj); + /* lookup_or_create_module_kobject took a reference */ + kobject_put(&mk->kobj); } } From 3dc33f145a8af9c7a3fb98259fa9dcc105dbe1b4 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Tue, 6 Aug 2024 20:31:15 -0300 Subject: [PATCH 4/7] iommu/arm-smmu-v3: Use the new rb tree helpers [ Upstream commit a2bb820e862d61f9ca1499e500915f9f505a2655 ] Since v5.12 the rbtree has gained some simplifying helpers aimed at making rb tree users write less convoluted boiler plate code. Instead the caller provides a single comparison function and the helpers generate the prior open-coded stuff. Update smmu->streams to use rb_find_add() and rb_find(). Tested-by: Nicolin Chen Reviewed-by: Mostafa Saleh Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/1-v3-9fef8cdc2ff6+150d1-smmuv3_tidy_jgg@nvidia.com Signed-off-by: Will Deacon Stable-dep-of: b00d24997a11 ("iommu/arm-smmu-v3: Fix iommu_device_probe bug due to duplicated stream ids") Signed-off-by: Sasha Levin --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 68 ++++++++++----------- 1 file changed, 31 insertions(+), 37 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 6cecbac0e6ba..2cab4798e7a0 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -1443,26 +1443,37 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid) return 0; } +static int arm_smmu_streams_cmp_key(const void *lhs, const struct rb_node *rhs) +{ + struct arm_smmu_stream *stream_rhs = + rb_entry(rhs, struct arm_smmu_stream, node); + const u32 *sid_lhs = lhs; + + if (*sid_lhs < stream_rhs->id) + return -1; + if (*sid_lhs > stream_rhs->id) + return 1; + return 0; +} + +static int arm_smmu_streams_cmp_node(struct rb_node *lhs, + const struct rb_node *rhs) +{ + return arm_smmu_streams_cmp_key( + &rb_entry(lhs, struct arm_smmu_stream, node)->id, rhs); +} + static struct arm_smmu_master * arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid) { struct rb_node *node; - struct arm_smmu_stream *stream; lockdep_assert_held(&smmu->streams_mutex); - node = smmu->streams.rb_node; - while (node) { - stream = rb_entry(node, struct arm_smmu_stream, node); - if (stream->id < sid) - node = node->rb_right; - else if (stream->id > sid) - node = node->rb_left; - else - return stream->master; - } - - return NULL; + node = rb_find(&sid, &smmu->streams, arm_smmu_streams_cmp_key); + if (!node) + return NULL; + return rb_entry(node, struct arm_smmu_stream, node)->master; } /* IRQ and event handlers */ @@ -2575,8 +2586,6 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, { int i; int ret = 0; - struct arm_smmu_stream *new_stream, *cur_stream; - struct rb_node **new_node, *parent_node = NULL; struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(master->dev); master->streams = kcalloc(fwspec->num_ids, sizeof(*master->streams), @@ -2587,9 +2596,9 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, mutex_lock(&smmu->streams_mutex); for (i = 0; i < fwspec->num_ids; i++) { + struct arm_smmu_stream *new_stream = &master->streams[i]; u32 sid = fwspec->ids[i]; - new_stream = &master->streams[i]; new_stream->id = sid; new_stream->master = master; @@ -2598,28 +2607,13 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, break; /* Insert into SID tree */ - new_node = &(smmu->streams.rb_node); - while (*new_node) { - cur_stream = rb_entry(*new_node, struct arm_smmu_stream, - node); - parent_node = *new_node; - if (cur_stream->id > new_stream->id) { - new_node = &((*new_node)->rb_left); - } else if (cur_stream->id < new_stream->id) { - new_node = &((*new_node)->rb_right); - } else { - dev_warn(master->dev, - "stream %u already in tree\n", - cur_stream->id); - ret = -EINVAL; - break; - } - } - if (ret) + if (rb_find_add(&new_stream->node, &smmu->streams, + arm_smmu_streams_cmp_node)) { + dev_warn(master->dev, "stream %u already in tree\n", + sid); + ret = -EINVAL; break; - - rb_link_node(&new_stream->node, parent_node, new_node); - rb_insert_color(&new_stream->node, &smmu->streams); + } } if (ret) { From 4306dbd7676e41032813620e49cd821a25559852 Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Tue, 15 Apr 2025 11:56:20 -0700 Subject: [PATCH 5/7] iommu/arm-smmu-v3: Fix iommu_device_probe bug due to duplicated stream ids [ Upstream commit b00d24997a11c10d3e420614f0873b83ce358a34 ] ASPEED VGA card has two built-in devices: 0008:06:00.0 PCI bridge: ASPEED Technology, Inc. AST1150 PCI-to-PCI Bridge (rev 06) 0008:07:00.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 52) Its toplogy looks like this: +-[0008:00]---00.0-[01-09]--+-00.0-[02-09]--+-00.0-[03]----00.0 Sandisk Corp Device 5017 | +-01.0-[04]-- | +-02.0-[05]----00.0 NVIDIA Corporation Device | +-03.0-[06-07]----00.0-[07]----00.0 ASPEED Technology, Inc. ASPEED Graphics Family | +-04.0-[08]----00.0 Renesas Technology Corp. uPD720201 USB 3.0 Host Controller | \-05.0-[09]----00.0 Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller \-00.1 PMC-Sierra Inc. Device 4028 The IORT logic populaties two identical IDs into the fwspec->ids array via DMA aliasing in iort_pci_iommu_init() called by pci_for_each_dma_alias(). Though the SMMU driver had been able to handle this situation since commit 563b5cbe334e ("iommu/arm-smmu-v3: Cope with duplicated Stream IDs"), that got broken by the later commit cdf315f907d4 ("iommu/arm-smmu-v3: Maintain a SID->device structure"), which ended up with allocating separate streams with the same stuffing. On a kernel prior to v6.15-rc1, there has been an overlooked warning: pci 0008:07:00.0: vgaarb: setting as boot VGA device pci 0008:07:00.0: vgaarb: bridge control possible pci 0008:07:00.0: vgaarb: VGA device added: decodes=io+mem,owns=none,locks=none pcieport 0008:06:00.0: Adding to iommu group 14 ast 0008:07:00.0: stream 67328 already in tree <===== WARNING ast 0008:07:00.0: enabling device (0002 -> 0003) ast 0008:07:00.0: Using default configuration ast 0008:07:00.0: AST 2600 detected ast 0008:07:00.0: [drm] Using analog VGA ast 0008:07:00.0: [drm] dram MCLK=396 Mhz type=1 bus_width=16 [drm] Initialized ast 0.1.0 for 0008:07:00.0 on minor 0 ast 0008:07:00.0: [drm] fb0: astdrmfb frame buffer device With v6.15-rc, since the commit bcb81ac6ae3c ("iommu: Get DT/ACPI parsing into the proper probe path"), the error returned with the warning is moved to the SMMU device probe flow: arm_smmu_probe_device+0x15c/0x4c0 __iommu_probe_device+0x150/0x4f8 probe_iommu_group+0x44/0x80 bus_for_each_dev+0x7c/0x100 bus_iommu_probe+0x48/0x1a8 iommu_device_register+0xb8/0x178 arm_smmu_device_probe+0x1350/0x1db0 which then fails the entire SMMU driver probe: pci 0008:06:00.0: Adding to iommu group 21 pci 0008:07:00.0: stream 67328 already in tree arm-smmu-v3 arm-smmu-v3.9.auto: Failed to register iommu arm-smmu-v3 arm-smmu-v3.9.auto: probe with driver arm-smmu-v3 failed with error -22 Since SMMU driver had been already expecting a potential duplicated Stream ID in arm_smmu_install_ste_for_dev(), change the arm_smmu_insert_master() routine to ignore a duplicated ID from the fwspec->sids array as well. Note: this has been failing the iommu_device_probe() since 2021, although a recent iommu commit in v6.15-rc1 that moves iommu_device_probe() started to fail the SMMU driver probe. Since nobody has cared about DMA Alias support, leave that as it was but fix the fundamental iommu_device_probe() breakage. Fixes: cdf315f907d4 ("iommu/arm-smmu-v3: Maintain a SID->device structure") Cc: stable@vger.kernel.org Suggested-by: Jason Gunthorpe Reviewed-by: Jason Gunthorpe Signed-off-by: Nicolin Chen Link: https://lore.kernel.org/r/20250415185620.504299-1-nicolinc@nvidia.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 2cab4798e7a0..f2260f45728e 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2597,6 +2597,7 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, mutex_lock(&smmu->streams_mutex); for (i = 0; i < fwspec->num_ids; i++) { struct arm_smmu_stream *new_stream = &master->streams[i]; + struct rb_node *existing; u32 sid = fwspec->ids[i]; new_stream->id = sid; @@ -2607,10 +2608,20 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, break; /* Insert into SID tree */ - if (rb_find_add(&new_stream->node, &smmu->streams, - arm_smmu_streams_cmp_node)) { - dev_warn(master->dev, "stream %u already in tree\n", - sid); + existing = rb_find_add(&new_stream->node, &smmu->streams, + arm_smmu_streams_cmp_node); + if (existing) { + struct arm_smmu_master *existing_master = + rb_entry(existing, struct arm_smmu_stream, node) + ->master; + + /* Bridged PCI devices may end up with duplicated IDs */ + if (existing_master == master) + continue; + + dev_warn(master->dev, + "stream %u already in tree from dev %s\n", sid, + dev_name(existing_master->dev)); ret = -EINVAL; break; } From 97a918755a4ca990a372729a4de70d87a31bb93a Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Fri, 28 Feb 2025 13:30:01 -0600 Subject: [PATCH 6/7] drm/amd/display: Add scoped mutexes for amdgpu_dm_dhcp [ Upstream commit 6b675ab8efbf2bcee25be29e865455c56e246401 ] [Why] Guards automatically release mutex when it goes out of scope making code easier to follow. [How] Replace all use of mutex_lock()/mutex_unlock() with guard(mutex). Reviewed-by: Alex Hung Signed-off-by: Mario Limonciello Signed-off-by: Tom Chung Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Stable-dep-of: be593d9d91c5 ("drm/amd/display: Fix slab-use-after-free in hdcp") Signed-off-by: Sasha Levin --- .../amd/display/amdgpu_dm/amdgpu_dm_hdcp.c | 37 +++++-------------- 1 file changed, 10 insertions(+), 27 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c index 2ad9f900a857..4330d37022fa 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c @@ -172,7 +172,7 @@ void hdcp_update_display(struct hdcp_workqueue *hdcp_work, struct mod_hdcp_display_adjustment display_adjust; unsigned int conn_index = aconnector->base.index; - mutex_lock(&hdcp_w->mutex); + guard(mutex)(&hdcp_w->mutex); hdcp_w->aconnector[conn_index] = aconnector; memset(&link_adjust, 0, sizeof(link_adjust)); @@ -209,7 +209,6 @@ void hdcp_update_display(struct hdcp_workqueue *hdcp_work, mod_hdcp_update_display(&hdcp_w->hdcp, conn_index, &link_adjust, &display_adjust, &hdcp_w->output); process_output(hdcp_w); - mutex_unlock(&hdcp_w->mutex); } static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, @@ -220,7 +219,7 @@ static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, struct drm_connector_state *conn_state = aconnector->base.state; unsigned int conn_index = aconnector->base.index; - mutex_lock(&hdcp_w->mutex); + guard(mutex)(&hdcp_w->mutex); hdcp_w->aconnector[conn_index] = aconnector; /* the removal of display will invoke auth reset -> hdcp destroy and @@ -239,7 +238,6 @@ static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, mod_hdcp_remove_display(&hdcp_w->hdcp, aconnector->base.index, &hdcp_w->output); process_output(hdcp_w); - mutex_unlock(&hdcp_w->mutex); } void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_index) @@ -247,7 +245,7 @@ void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_inde struct hdcp_workqueue *hdcp_w = &hdcp_work[link_index]; unsigned int conn_index; - mutex_lock(&hdcp_w->mutex); + guard(mutex)(&hdcp_w->mutex); mod_hdcp_reset_connection(&hdcp_w->hdcp, &hdcp_w->output); @@ -259,8 +257,6 @@ void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_inde } process_output(hdcp_w); - - mutex_unlock(&hdcp_w->mutex); } void hdcp_handle_cpirq(struct hdcp_workqueue *hdcp_work, unsigned int link_index) @@ -277,7 +273,7 @@ static void event_callback(struct work_struct *work) hdcp_work = container_of(to_delayed_work(work), struct hdcp_workqueue, callback_dwork); - mutex_lock(&hdcp_work->mutex); + guard(mutex)(&hdcp_work->mutex); cancel_delayed_work(&hdcp_work->callback_dwork); @@ -285,8 +281,6 @@ static void event_callback(struct work_struct *work) &hdcp_work->output); process_output(hdcp_work); - - mutex_unlock(&hdcp_work->mutex); } static void event_property_update(struct work_struct *work) @@ -323,7 +317,7 @@ static void event_property_update(struct work_struct *work) continue; drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); - mutex_lock(&hdcp_work->mutex); + guard(mutex)(&hdcp_work->mutex); if (conn_state->commit) { ret = wait_for_completion_interruptible_timeout(&conn_state->commit->hw_done, @@ -355,7 +349,6 @@ static void event_property_update(struct work_struct *work) drm_hdcp_update_content_protection(connector, DRM_MODE_CONTENT_PROTECTION_DESIRED); } - mutex_unlock(&hdcp_work->mutex); drm_modeset_unlock(&dev->mode_config.connection_mutex); } } @@ -368,7 +361,7 @@ static void event_property_validate(struct work_struct *work) struct amdgpu_dm_connector *aconnector; unsigned int conn_index; - mutex_lock(&hdcp_work->mutex); + guard(mutex)(&hdcp_work->mutex); for (conn_index = 0; conn_index < AMDGPU_DM_MAX_DISPLAY_INDEX; conn_index++) { @@ -408,8 +401,6 @@ static void event_property_validate(struct work_struct *work) schedule_work(&hdcp_work->property_update_work); } } - - mutex_unlock(&hdcp_work->mutex); } static void event_watchdog_timer(struct work_struct *work) @@ -420,7 +411,7 @@ static void event_watchdog_timer(struct work_struct *work) struct hdcp_workqueue, watchdog_timer_dwork); - mutex_lock(&hdcp_work->mutex); + guard(mutex)(&hdcp_work->mutex); cancel_delayed_work(&hdcp_work->watchdog_timer_dwork); @@ -429,8 +420,6 @@ static void event_watchdog_timer(struct work_struct *work) &hdcp_work->output); process_output(hdcp_work); - - mutex_unlock(&hdcp_work->mutex); } static void event_cpirq(struct work_struct *work) @@ -439,13 +428,11 @@ static void event_cpirq(struct work_struct *work) hdcp_work = container_of(work, struct hdcp_workqueue, cpirq_work); - mutex_lock(&hdcp_work->mutex); + guard(mutex)(&hdcp_work->mutex); mod_hdcp_process_event(&hdcp_work->hdcp, MOD_HDCP_EVENT_CPIRQ, &hdcp_work->output); process_output(hdcp_work); - - mutex_unlock(&hdcp_work->mutex); } void hdcp_destroy(struct kobject *kobj, struct hdcp_workqueue *hdcp_work) @@ -479,7 +466,7 @@ static bool enable_assr(void *handle, struct dc_link *link) dtm_cmd = (struct ta_dtm_shared_memory *)psp->dtm_context.context.mem_context.shared_buf; - mutex_lock(&psp->dtm_context.mutex); + guard(mutex)(&psp->dtm_context.mutex); memset(dtm_cmd, 0, sizeof(struct ta_dtm_shared_memory)); dtm_cmd->cmd_id = TA_DTM_COMMAND__TOPOLOGY_ASSR_ENABLE; @@ -494,8 +481,6 @@ static bool enable_assr(void *handle, struct dc_link *link) res = false; } - mutex_unlock(&psp->dtm_context.mutex); - return res; } @@ -557,13 +542,11 @@ static void update_config(void *handle, struct cp_psp_stream_config *config) (!!aconnector->base.state) ? aconnector->base.state->hdcp_content_type : -1); - mutex_lock(&hdcp_w->mutex); + guard(mutex)(&hdcp_w->mutex); mod_hdcp_add_display(&hdcp_w->hdcp, link, display, &hdcp_w->output); process_output(hdcp_w); - mutex_unlock(&hdcp_w->mutex); - } /** From bbc66abcd297be67e3d835276e21e6fdc65205a6 Mon Sep 17 00:00:00 2001 From: Chris Bainbridge Date: Thu, 17 Apr 2025 16:50:05 -0500 Subject: [PATCH 7/7] drm/amd/display: Fix slab-use-after-free in hdcp [ Upstream commit be593d9d91c5a3a363d456b9aceb71029aeb3f1d ] The HDCP code in amdgpu_dm_hdcp.c copies pointers to amdgpu_dm_connector objects without incrementing the kref reference counts. When using a USB-C dock, and the dock is unplugged, the corresponding amdgpu_dm_connector objects are freed, creating dangling pointers in the HDCP code. When the dock is plugged back, the dangling pointers are dereferenced, resulting in a slab-use-after-free: [ 66.775837] BUG: KASAN: slab-use-after-free in event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.776171] Read of size 4 at addr ffff888127804120 by task kworker/0:1/10 [ 66.776179] CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.14.0-rc7-00180-g54505f727a38-dirty #233 [ 66.776183] Hardware name: HP HP Pavilion Aero Laptop 13-be0xxx/8916, BIOS F.17 12/18/2024 [ 66.776186] Workqueue: events event_property_validate [amdgpu] [ 66.776494] Call Trace: [ 66.776496] [ 66.776497] dump_stack_lvl+0x70/0xa0 [ 66.776504] print_report+0x175/0x555 [ 66.776507] ? __virt_addr_valid+0x243/0x450 [ 66.776510] ? kasan_complete_mode_report_info+0x66/0x1c0 [ 66.776515] kasan_report+0xeb/0x1c0 [ 66.776518] ? event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.776819] ? event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.777121] __asan_report_load4_noabort+0x14/0x20 [ 66.777124] event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.777342] ? __lock_acquire+0x6b40/0x6b40 [ 66.777347] ? enable_assr+0x250/0x250 [amdgpu] [ 66.777571] process_one_work+0x86b/0x1510 [ 66.777575] ? pwq_dec_nr_in_flight+0xcf0/0xcf0 [ 66.777578] ? assign_work+0x16b/0x280 [ 66.777580] ? lock_is_held_type+0xa3/0x130 [ 66.777583] worker_thread+0x5c0/0xfa0 [ 66.777587] ? process_one_work+0x1510/0x1510 [ 66.777588] kthread+0x3a2/0x840 [ 66.777591] ? kthread_is_per_cpu+0xd0/0xd0 [ 66.777594] ? trace_hardirqs_on+0x4f/0x60 [ 66.777597] ? _raw_spin_unlock_irq+0x27/0x60 [ 66.777599] ? calculate_sigpending+0x77/0xa0 [ 66.777602] ? kthread_is_per_cpu+0xd0/0xd0 [ 66.777605] ret_from_fork+0x40/0x90 [ 66.777607] ? kthread_is_per_cpu+0xd0/0xd0 [ 66.777609] ret_from_fork_asm+0x11/0x20 [ 66.777614] [ 66.777643] Allocated by task 10: [ 66.777646] kasan_save_stack+0x39/0x60 [ 66.777649] kasan_save_track+0x14/0x40 [ 66.777652] kasan_save_alloc_info+0x37/0x50 [ 66.777655] __kasan_kmalloc+0xbb/0xc0 [ 66.777658] __kmalloc_cache_noprof+0x1c8/0x4b0 [ 66.777661] dm_dp_add_mst_connector+0xdd/0x5c0 [amdgpu] [ 66.777880] drm_dp_mst_port_add_connector+0x47e/0x770 [drm_display_helper] [ 66.777892] drm_dp_send_link_address+0x1554/0x2bf0 [drm_display_helper] [ 66.777901] drm_dp_check_and_send_link_address+0x187/0x1f0 [drm_display_helper] [ 66.777909] drm_dp_mst_link_probe_work+0x2b8/0x410 [drm_display_helper] [ 66.777917] process_one_work+0x86b/0x1510 [ 66.777919] worker_thread+0x5c0/0xfa0 [ 66.777922] kthread+0x3a2/0x840 [ 66.777925] ret_from_fork+0x40/0x90 [ 66.777927] ret_from_fork_asm+0x11/0x20 [ 66.777932] Freed by task 1713: [ 66.777935] kasan_save_stack+0x39/0x60 [ 66.777938] kasan_save_track+0x14/0x40 [ 66.777940] kasan_save_free_info+0x3b/0x60 [ 66.777944] __kasan_slab_free+0x52/0x70 [ 66.777946] kfree+0x13f/0x4b0 [ 66.777949] dm_dp_mst_connector_destroy+0xfa/0x150 [amdgpu] [ 66.778179] drm_connector_free+0x7d/0xb0 [ 66.778184] drm_mode_object_put.part.0+0xee/0x160 [ 66.778188] drm_mode_object_put+0x37/0x50 [ 66.778191] drm_atomic_state_default_clear+0x220/0xd60 [ 66.778194] __drm_atomic_state_free+0x16e/0x2a0 [ 66.778197] drm_mode_atomic_ioctl+0x15ed/0x2ba0 [ 66.778200] drm_ioctl_kernel+0x17a/0x310 [ 66.778203] drm_ioctl+0x584/0xd10 [ 66.778206] amdgpu_drm_ioctl+0xd2/0x1c0 [amdgpu] [ 66.778375] __x64_sys_ioctl+0x139/0x1a0 [ 66.778378] x64_sys_call+0xee7/0xfb0 [ 66.778381] do_syscall_64+0x87/0x140 [ 66.778385] entry_SYSCALL_64_after_hwframe+0x4b/0x53 Fix this by properly incrementing and decrementing the reference counts when making and deleting copies of the amdgpu_dm_connector pointers. (Mario: rebase on current code and update fixes tag) Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4006 Signed-off-by: Chris Bainbridge Fixes: da3fd7ac0bcf3 ("drm/amd/display: Update CP property based on HW query") Reviewed-by: Alex Hung Link: https://lore.kernel.org/r/20250417215005.37964-1-mario.limonciello@amd.com Signed-off-by: Mario Limonciello Signed-off-by: Alex Deucher (cherry picked from commit d4673f3c3b3dcb74e36e53cdfc880baa7a87b330) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin --- .../amd/display/amdgpu_dm/amdgpu_dm_hdcp.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c index 4330d37022fa..a048022d9865 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c @@ -173,6 +173,9 @@ void hdcp_update_display(struct hdcp_workqueue *hdcp_work, unsigned int conn_index = aconnector->base.index; guard(mutex)(&hdcp_w->mutex); + drm_connector_get(&aconnector->base); + if (hdcp_w->aconnector[conn_index]) + drm_connector_put(&hdcp_w->aconnector[conn_index]->base); hdcp_w->aconnector[conn_index] = aconnector; memset(&link_adjust, 0, sizeof(link_adjust)); @@ -220,7 +223,6 @@ static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, unsigned int conn_index = aconnector->base.index; guard(mutex)(&hdcp_w->mutex); - hdcp_w->aconnector[conn_index] = aconnector; /* the removal of display will invoke auth reset -> hdcp destroy and * we'd expect the Content Protection (CP) property changed back to @@ -236,7 +238,10 @@ static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, } mod_hdcp_remove_display(&hdcp_w->hdcp, aconnector->base.index, &hdcp_w->output); - + if (hdcp_w->aconnector[conn_index]) { + drm_connector_put(&hdcp_w->aconnector[conn_index]->base); + hdcp_w->aconnector[conn_index] = NULL; + } process_output(hdcp_w); } @@ -254,6 +259,10 @@ void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_inde for (conn_index = 0; conn_index < AMDGPU_DM_MAX_DISPLAY_INDEX; conn_index++) { hdcp_w->encryption_status[conn_index] = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF; + if (hdcp_w->aconnector[conn_index]) { + drm_connector_put(&hdcp_w->aconnector[conn_index]->base); + hdcp_w->aconnector[conn_index] = NULL; + } } process_output(hdcp_w); @@ -489,6 +498,7 @@ static void update_config(void *handle, struct cp_psp_stream_config *config) struct hdcp_workqueue *hdcp_work = handle; struct amdgpu_dm_connector *aconnector = config->dm_stream_ctx; int link_index = aconnector->dc_link->link_index; + unsigned int conn_index = aconnector->base.index; struct mod_hdcp_display *display = &hdcp_work[link_index].display; struct mod_hdcp_link *link = &hdcp_work[link_index].link; struct hdcp_workqueue *hdcp_w = &hdcp_work[link_index]; @@ -545,7 +555,10 @@ static void update_config(void *handle, struct cp_psp_stream_config *config) guard(mutex)(&hdcp_w->mutex); mod_hdcp_add_display(&hdcp_w->hdcp, link, display, &hdcp_w->output); - + drm_connector_get(&aconnector->base); + if (hdcp_w->aconnector[conn_index]) + drm_connector_put(&hdcp_w->aconnector[conn_index]->base); + hdcp_w->aconnector[conn_index] = aconnector; process_output(hdcp_w); }