From 0a5e695095c557d2380131b613dea4e8d90371be Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:25 +0100 Subject: [PATCH 01/11] firmware: arm_ffa: Check for NULL FF-A ID table while driver registration The bus match callback assumes that every FF-A driver provides an id_table and dereferences it unconditionally. Enforce that contract at registration time so a buggy client driver cannot crash the bus during match. Fixes: 92743071464f ("firmware: arm_ffa: Ensure drivers provide a probe function") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-1-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/bus.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/arm_ffa/bus.c b/drivers/firmware/arm_ffa/bus.c index 9576862d89c4..601c3418e0d9 100644 --- a/drivers/firmware/arm_ffa/bus.c +++ b/drivers/firmware/arm_ffa/bus.c @@ -26,6 +26,8 @@ static int ffa_device_match(struct device *dev, const struct device_driver *drv) id_table = to_ffa_driver(drv)->id_table; ffa_dev = to_ffa_dev(dev); + if (!id_table) + return 0; while (!uuid_is_null(&id_table->uuid)) { /* @@ -123,7 +125,7 @@ int ffa_driver_register(struct ffa_driver *driver, struct module *owner, { int ret; - if (!driver->probe) + if (!driver->probe || !driver->id_table) return -EINVAL; driver->driver.bus = &ffa_bus_type; From 09527e2c534911619d7e098729711100290bc3e1 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:26 +0100 Subject: [PATCH 02/11] firmware: arm_ffa: Skip free_pages on RX buffer alloc failure If the RX buffer allocation fails in ffa_init(), the error path jumps to free_pages even though no buffer has been allocated yet. Route that case directly to free_drv_info so the cleanup path is only used after at least one RX/TX buffer allocation has succeeded. Fixes: 3bbfe9871005 ("firmware: arm_ffa: Add initial Arm FFA driver support") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-2-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index eb2782848283..e6a051b20cb7 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -2067,7 +2067,7 @@ static int __init ffa_init(void) drv_info->rx_buffer = alloc_pages_exact(rxtx_bufsz, GFP_KERNEL); if (!drv_info->rx_buffer) { ret = -ENOMEM; - goto free_pages; + goto free_drv_info; } drv_info->tx_buffer = alloc_pages_exact(rxtx_bufsz, GFP_KERNEL); From 9b5597af8bc51c25342ab11896532644b181d302 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:27 +0100 Subject: [PATCH 03/11] firmware: arm_ffa: Avoid collapsing NPI work from different CPUs Notification pending interrupts are registered as per-CPU IRQs, but the driver queues all NPI handling through a single shared work_struct. That allows queue_work_on() calls from different CPUs to collapse onto a single pending work item even though the work function uses the CPU it runs on to fetch and handle per-CPU notifications. Move notif_pcpu_work into the per-CPU ffa_pcpu_irq state and initialize one work item per CPU. This keeps NPI handling independent per CPU and avoids losing notifications when multiple CPUs queue work concurrently. Link: https://patch.msgid.link/20260428-ffa_fixes-v2-3-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index e6a051b20cb7..4e66c7325a4e 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -87,6 +87,7 @@ static inline int ffa_to_linux_errno(int errno) struct ffa_pcpu_irq { struct ffa_drv_info *info; + struct work_struct notif_pcpu_work; }; struct ffa_drv_info { @@ -106,7 +107,6 @@ struct ffa_drv_info { unsigned int cpuhp_state; struct ffa_pcpu_irq __percpu *irq_pcpu; struct workqueue_struct *notif_pcpu_wq; - struct work_struct notif_pcpu_work; struct work_struct sched_recv_irq_work; struct xarray partition_info; DECLARE_HASHTABLE(notifier_hash, ilog2(FFA_MAX_NOTIFICATIONS)); @@ -1539,8 +1539,9 @@ ffa_self_notif_handle(u16 vcpu, bool is_per_vcpu, void *cb_data) static void notif_pcpu_irq_work_fn(struct work_struct *work) { - struct ffa_drv_info *info = container_of(work, struct ffa_drv_info, + struct ffa_pcpu_irq *pcpu = container_of(work, struct ffa_pcpu_irq, notif_pcpu_work); + struct ffa_drv_info *info = pcpu->info; ffa_self_notif_handle(smp_processor_id(), true, info); } @@ -1811,7 +1812,7 @@ static irqreturn_t notif_pend_irq_handler(int irq, void *irq_data) struct ffa_drv_info *info = pcpu->info; queue_work_on(smp_processor_id(), info->notif_pcpu_wq, - &info->notif_pcpu_work); + &pcpu->notif_pcpu_work); return IRQ_HANDLED; } @@ -1928,8 +1929,11 @@ static int ffa_init_pcpu_irq(void) if (!irq_pcpu) return -ENOMEM; - for_each_present_cpu(cpu) + for_each_present_cpu(cpu) { per_cpu_ptr(irq_pcpu, cpu)->info = drv_info; + INIT_WORK(&per_cpu_ptr(irq_pcpu, cpu)->notif_pcpu_work, + notif_pcpu_irq_work_fn); + } drv_info->irq_pcpu = irq_pcpu; @@ -1958,7 +1962,6 @@ static int ffa_init_pcpu_irq(void) } INIT_WORK(&drv_info->sched_recv_irq_work, ffa_sched_recv_irq_work_fn); - INIT_WORK(&drv_info->notif_pcpu_work, notif_pcpu_irq_work_fn); drv_info->notif_pcpu_wq = create_workqueue("ffa_pcpu_irq_notification"); if (!drv_info->notif_pcpu_wq) return -EINVAL; From 9985d5357ed93af0d1933969c247e966957730e1 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:28 +0100 Subject: [PATCH 04/11] firmware: arm_ffa: Fix per-vcpu self notifications handling in workqueue Per-vcpu notification handling already runs from a per-cpu work item on the target cpu. Routing that path back through smp_call_function_single() re-enters the call-function IPI path and executes the notification handler with interrupts disabled. That makes the framework path unsafe, since it takes a mutex, allocates memory with GFP_KERNEL, and invokes client callbacks. Handle per-vcpu self notifications directly from the existing per-cpu work item instead. This keeps the per-vcpu path in task context and avoids the extra IPI hop entirely. Fixes: 3a3e2b83e805 ("firmware: arm_ffa: Avoid queuing work when running on the worker queue") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-4-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 4e66c7325a4e..2241e851f7ae 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -1543,7 +1543,7 @@ static void notif_pcpu_irq_work_fn(struct work_struct *work) notif_pcpu_work); struct ffa_drv_info *info = pcpu->info; - ffa_self_notif_handle(smp_processor_id(), true, info); + notif_get_and_handle(info); } static const struct ffa_info_ops ffa_drv_info_ops = { From 6d3daa9b8d313f42d52e75590310f26a29b61b44 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:29 +0100 Subject: [PATCH 05/11] firmware: arm_ffa: Unregister bus notifier on teardown for FF-A v1.0 For FF-A v1.0 the driver registers a bus notifier to backfill UUID matching, but the notifier was never unregistered on cleanup paths. Track the registration state and unregister it during teardown and early partition-setup failure. Fixes: 9dd15934f60d ("firmware: arm_ffa: Move the FF-A v1.0 NULL UUID workaround to bus notifier") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-5-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 2241e851f7ae..a122814eb6d7 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -101,6 +101,7 @@ struct ffa_drv_info { bool mem_ops_native; bool msg_direct_req2_supp; bool bitmap_created; + bool bus_notifier_registered; bool notif_enabled; unsigned int sched_recv_irq; unsigned int notif_pend_irq; @@ -1630,6 +1631,15 @@ static struct notifier_block ffa_bus_nb = { .notifier_call = ffa_bus_notifier, }; +static void ffa_bus_notifier_unregister(void) +{ + if (!drv_info->bus_notifier_registered) + return; + + bus_unregister_notifier(&ffa_bus_type, &ffa_bus_nb); + drv_info->bus_notifier_registered = false; +} + static int ffa_xa_add_partition_info(struct ffa_device *dev) { struct ffa_dev_part_info *info; @@ -1713,6 +1723,8 @@ static void ffa_partitions_cleanup(void) struct list_head *phead; unsigned long idx; + ffa_bus_notifier_unregister(); + /* Clean up/free all registered devices */ ffa_devices_unregister(); @@ -1740,11 +1752,14 @@ static int ffa_setup_partitions(void) ret = bus_register_notifier(&ffa_bus_type, &ffa_bus_nb); if (ret) pr_err("Failed to register FF-A bus notifiers\n"); + else + drv_info->bus_notifier_registered = true; } count = ffa_partition_probe(&uuid_null, &pbuf); if (count <= 0) { pr_info("%s: No partitions found, error %d\n", __func__, count); + ffa_bus_notifier_unregister(); return -EINVAL; } From 3974ea1938406f9bfa7c1f48d4e43533f447bb08 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:30 +0100 Subject: [PATCH 06/11] firmware: arm_ffa: Bound PARTITION_INFO_GET_REGS copies The register-based PARTITION_INFO_GET path trusted the firmware-provided indices when copying partition descriptors into the caller buffer. Reject inconsistent counts or index progressions so the copy loop cannot write past the allocated array. Fixes: ba85c644ac8d ("firmware: arm_ffa: Add support for FFA_PARTITION_INFO_GET_REGS") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-6-8595ae450034@kernel.org (fixed cur_idx when exactly one descriptor in the first fragment) Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index a122814eb6d7..33b417e78684 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -323,6 +323,12 @@ __ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3, #define PART_INFO_ID_MASK GENMASK(15, 0) #define PART_INFO_EXEC_CXT_MASK GENMASK(31, 16) #define PART_INFO_PROPS_MASK GENMASK(63, 32) +#define FFA_PART_INFO_GET_REGS_FIRST_REG 3 +#define FFA_PART_INFO_GET_REGS_REGS_PER_DESC 3 +#define FFA_PART_INFO_GET_REGS_MAX_DESC \ + (((sizeof(ffa_value_t) / sizeof_field(ffa_value_t, a0)) - \ + FFA_PART_INFO_GET_REGS_FIRST_REG) / \ + FFA_PART_INFO_GET_REGS_REGS_PER_DESC) #define PART_INFO_ID(x) ((u16)(FIELD_GET(PART_INFO_ID_MASK, (x)))) #define PART_INFO_EXEC_CXT(x) ((u16)(FIELD_GET(PART_INFO_EXEC_CXT_MASK, (x)))) #define PART_INFO_PROPERTIES(x) ((u32)(FIELD_GET(PART_INFO_PROPS_MASK, (x)))) @@ -330,15 +336,13 @@ static int __ffa_partition_info_get_regs(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3, struct ffa_partition_info *buffer, int num_parts) { - u16 buf_sz, start_idx, cur_idx, count = 0, prev_idx = 0, tag = 0; + u16 buf_sz, start_idx = 0, cur_idx, count = 0, tag = 0; struct ffa_partition_info *buf = buffer; ffa_value_t partition_info; do { __le64 *regs; - int idx; - - start_idx = prev_idx ? prev_idx + 1 : 0; + int idx, nr_desc, buf_idx; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_PARTITION_INFO_GET_REGS, @@ -354,15 +358,28 @@ __ffa_partition_info_get_regs(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3, count = PARTITION_COUNT(partition_info.a2); if (!buffer || !num_parts) /* count only */ return count; + if (count > num_parts) + return -EINVAL; cur_idx = CURRENT_INDEX(partition_info.a2); + if (cur_idx < start_idx || cur_idx >= count) + return -EINVAL; + + nr_desc = cur_idx - start_idx + 1; + if (nr_desc > FFA_PART_INFO_GET_REGS_MAX_DESC) + return -EINVAL; + + buf_idx = buf - buffer; + if (buf_idx + nr_desc > num_parts) + return -EINVAL; + tag = UUID_INFO_TAG(partition_info.a2); buf_sz = PARTITION_INFO_SZ(partition_info.a2); if (buf_sz > sizeof(*buffer)) buf_sz = sizeof(*buffer); regs = (void *)&partition_info.a3; - for (idx = 0; idx < cur_idx - start_idx + 1; idx++, buf++) { + for (idx = 0; idx < nr_desc; idx++, buf++) { union { uuid_t uuid; u64 regs[2]; @@ -380,7 +397,7 @@ __ffa_partition_info_get_regs(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3, uuid_copy(&buf->uuid, &uuid_regs.uuid); regs += 3; } - prev_idx = cur_idx; + start_idx = cur_idx + 1; } while (cur_idx < (count - 1)); From 2af18f8e36b277730527cacc2256b1332f56aa28 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:31 +0100 Subject: [PATCH 07/11] firmware: arm_ffa: Keep framework RX release under lock The framework notification handler drops rx_lock before issuing FFA_RX_RELEASE, leaving a window where another RX-buffer user can start a new FF-A transaction before ownership has actually been returned to firmware. Move the FFA_RX_RELEASE calls so they execute while rx_lock is still held on both the kmemdup() failure path and the normal success path. While doing that, switch the handler to scoped_guard() to keep the critical section explicit. Fixes: 285a5ea0f542 ("firmware: arm_ffa: Add support for handling framework notifications") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-7-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 29 +++++++++++++---------------- 1 file changed, 13 insertions(+), 16 deletions(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 33b417e78684..d1e70866a425 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -1492,25 +1492,22 @@ static void handle_fwk_notif_callbacks(u32 bitmap) if (!(bitmap & FRAMEWORK_NOTIFY_RX_BUFFER_FULL)) return; - mutex_lock(&drv_info->rx_lock); + scoped_guard(mutex, &drv_info->rx_lock) { + msg = drv_info->rx_buffer; + buf = kmemdup((void *)msg + msg->offset, msg->size, GFP_KERNEL); + if (!buf) { + ffa_rx_release(); + return; + } - msg = drv_info->rx_buffer; - buf = kmemdup((void *)msg + msg->offset, msg->size, GFP_KERNEL); - if (!buf) { - mutex_unlock(&drv_info->rx_lock); - return; + target = SENDER_ID(msg->send_recv_id); + if (msg->offset >= sizeof(*msg)) + uuid_copy(&uuid, &msg->uuid); + else + uuid_copy(&uuid, &uuid_null); + ffa_rx_release(); } - target = SENDER_ID(msg->send_recv_id); - if (msg->offset >= sizeof(*msg)) - uuid_copy(&uuid, &msg->uuid); - else - uuid_copy(&uuid, &uuid_null); - - mutex_unlock(&drv_info->rx_lock); - - ffa_rx_release(); - read_lock(&drv_info->notify_lock); cb_info = notifier_hnode_get_by_vmid_uuid(notify_id, target, &uuid); read_unlock(&drv_info->notify_lock); From 4a1cc9e96b311d2609a6f963a5e35bd4ae730d97 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:32 +0100 Subject: [PATCH 08/11] firmware: arm_ffa: Validate framework notification message layout Framework notifications carry an indirect message in the shared RX buffer. Validate the reported offset and size before using them, reject zero-length payloads, and ensure that any non-header payload starts at the UUID field rather than in the middle of the message header. Use the validated offset and size values for both kmemdup() and the UUID parsing path so malformed firmware data cannot drive an out-of-bounds read or an oversized allocation. Fixes: 285a5ea0f542 ("firmware: arm_ffa: Add support for handling framework notifications") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-8-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index d1e70866a425..7287423faceb 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -1487,21 +1487,35 @@ static void handle_fwk_notif_callbacks(u32 bitmap) int notify_id = 0, target; struct ffa_indirect_msg_hdr *msg; struct notifier_cb_info *cb_info = NULL; + size_t min_offset = offsetof(struct ffa_indirect_msg_hdr, uuid); /* Only one framework notification defined and supported for now */ if (!(bitmap & FRAMEWORK_NOTIFY_RX_BUFFER_FULL)) return; scoped_guard(mutex, &drv_info->rx_lock) { + u32 offset, size; + msg = drv_info->rx_buffer; - buf = kmemdup((void *)msg + msg->offset, msg->size, GFP_KERNEL); + offset = msg->offset; + size = msg->size; + + if (!size || (offset != min_offset && offset < sizeof(*msg)) || + offset > drv_info->rxtx_bufsz || + size > drv_info->rxtx_bufsz - offset) { + pr_err("invalid framework notification message\n"); + ffa_rx_release(); + return; + } + + buf = kmemdup((void *)msg + offset, size, GFP_KERNEL); if (!buf) { ffa_rx_release(); return; } target = SENDER_ID(msg->send_recv_id); - if (msg->offset >= sizeof(*msg)) + if (offset >= sizeof(*msg)) uuid_copy(&uuid, &msg->uuid); else uuid_copy(&uuid, &uuid_null); From 0399e3f872ca3d78044bb715a73ea645806d2c7b Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:33 +0100 Subject: [PATCH 09/11] firmware: arm_ffa: Align RxTx buffer size before mapping Commit 83210251fd70 ("firmware: arm_ffa: Use the correct buffer size during RXTX_MAP") advertises PAGE_ALIGN(rxtx_bufsz) to firmware when mapping the buffers but the driver continues to stores the minimum FF-A buffer size in drv_info->rxtx_bufsz which is used elsewhere in the driver. Align the size before storing it so that the allocation, validation and FFA_RXTX_MAP all use the same buffer size. Fixes: 83210251fd70 ("firmware: arm_ffa: Use the correct buffer size during RXTX_MAP") Cc: Sebastian Ene Link: https://sashiko.dev/#/patchset/20260402113939.930221-1-sebastianene@google.com Reviewed-by: Sebastian Ene Link: https://patch.msgid.link/20260428-ffa_fixes-v2-9-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 7287423faceb..66ed98e32bd6 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -2109,6 +2109,7 @@ static int __init ffa_init(void) rxtx_bufsz = SZ_4K; } + rxtx_bufsz = PAGE_ALIGN(rxtx_bufsz); drv_info->rxtx_bufsz = rxtx_bufsz; drv_info->rx_buffer = alloc_pages_exact(rxtx_bufsz, GFP_KERNEL); if (!drv_info->rx_buffer) { @@ -2124,7 +2125,7 @@ static int __init ffa_init(void) ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer), virt_to_phys(drv_info->rx_buffer), - PAGE_ALIGN(rxtx_bufsz) / FFA_PAGE_SIZE); + rxtx_bufsz / FFA_PAGE_SIZE); if (ret) { pr_err("failed to register FFA RxTx buffers\n"); goto free_pages; From 38290b180a4d5746baed796d49f88d56d2f336cd Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:34 +0100 Subject: [PATCH 10/11] firmware: arm_ffa: Snapshot notifier callbacks under lock Both notification handlers currently look up a notifier callback under notify_lock, drop the lock, and then dereference the returned notifier entry. A concurrent unregister can delete and free that entry in the gap, leaving the handler to dereference stale memory. Copy the callback pointer and callback data while notify_lock is still held and invoke the callback only after the lock is dropped. This keeps the existing callback execution model while removing the use-after-free window in both the framework and non-framework notification paths. Fixes: 285a5ea0f542 ("firmware: arm_ffa: Add support for handling framework notifications") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-10-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 35 ++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 12 deletions(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 66ed98e32bd6..98ead7ed28ca 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -1463,20 +1463,25 @@ static int ffa_notify_send(struct ffa_device *dev, int notify_id, static void handle_notif_callbacks(u64 bitmap, enum notify_type type) { + ffa_notifier_cb cb; + void *cb_data; int notify_id; - struct notifier_cb_info *cb_info = NULL; for (notify_id = 0; notify_id <= FFA_MAX_NOTIFICATIONS && bitmap; notify_id++, bitmap >>= 1) { if (!(bitmap & 1)) continue; - read_lock(&drv_info->notify_lock); - cb_info = notifier_hnode_get_by_type(notify_id, type); - read_unlock(&drv_info->notify_lock); + scoped_guard(read_lock, &drv_info->notify_lock) { + struct notifier_cb_info *cb_info; - if (cb_info && cb_info->cb) - cb_info->cb(notify_id, cb_info->cb_data); + cb_info = notifier_hnode_get_by_type(notify_id, type); + cb = cb_info ? cb_info->cb : NULL; + cb_data = cb_info ? cb_info->cb_data : NULL; + } + + if (cb) + cb(notify_id, cb_data); } } @@ -1484,9 +1489,10 @@ static void handle_fwk_notif_callbacks(u32 bitmap) { void *buf; uuid_t uuid; + void *fwk_cb_data; int notify_id = 0, target; + ffa_fwk_notifier_cb fwk_cb; struct ffa_indirect_msg_hdr *msg; - struct notifier_cb_info *cb_info = NULL; size_t min_offset = offsetof(struct ffa_indirect_msg_hdr, uuid); /* Only one framework notification defined and supported for now */ @@ -1522,12 +1528,17 @@ static void handle_fwk_notif_callbacks(u32 bitmap) ffa_rx_release(); } - read_lock(&drv_info->notify_lock); - cb_info = notifier_hnode_get_by_vmid_uuid(notify_id, target, &uuid); - read_unlock(&drv_info->notify_lock); + scoped_guard(read_lock, &drv_info->notify_lock) { + struct notifier_cb_info *cb_info; - if (cb_info && cb_info->fwk_cb) - cb_info->fwk_cb(notify_id, cb_info->cb_data, buf); + cb_info = notifier_hnode_get_by_vmid_uuid(notify_id, target, + &uuid); + fwk_cb = cb_info ? cb_info->fwk_cb : NULL; + fwk_cb_data = cb_info ? cb_info->cb_data : NULL; + } + + if (fwk_cb) + fwk_cb(notify_id, fwk_cb_data, buf); kfree(buf); } From a6848a50404eefb6f0b131c21881a2d8d21b31a9 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 28 Apr 2026 19:33:35 +0100 Subject: [PATCH 11/11] firmware: arm_ffa: Fix sched-recv callback partition lookup ffa_sched_recv_cb_update() used list_for_each_entry_safe() to search for a matching partition and then tested the iterator against NULL. That is not a valid end-of-list check for circular lists and can fall through with an invalid pointer. Use a normal iterator and detect the not-found case correctly before touching the partition state. Fixes: be61da938576 ("firmware: arm_ffa: Allow multiple UUIDs per partition to register SRI callback") Link: https://patch.msgid.link/20260428-ffa_fixes-v2-11-8595ae450034@kernel.org Signed-off-by: Sudeep Holla --- drivers/firmware/arm_ffa/driver.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 98ead7ed28ca..b9f17fda7243 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -1207,7 +1207,7 @@ static int ffa_sched_recv_cb_update(struct ffa_device *dev, ffa_sched_recv_cb callback, void *cb_data, bool is_registration) { - struct ffa_dev_part_info *partition = NULL, *tmp; + struct ffa_dev_part_info *partition = NULL; struct list_head *phead; bool cb_valid; @@ -1220,11 +1220,11 @@ ffa_sched_recv_cb_update(struct ffa_device *dev, ffa_sched_recv_cb callback, return -EINVAL; } - list_for_each_entry_safe(partition, tmp, phead, node) + list_for_each_entry(partition, phead, node) if (partition->dev == dev) break; - if (!partition) { + if (&partition->node == phead) { pr_err("%s: No such partition ID 0x%x\n", __func__, dev->vm_id); return -EINVAL; }