From f3f380ce6b3d5c9805c7e0b3d5bc28d9ec41e2e8 Mon Sep 17 00:00:00 2001 From: Kaushlendra Kumar Date: Mon, 5 Jan 2026 08:48:20 +0530 Subject: regmap: maple: free entry on mas_store_gfp() failure regcache_maple_write() allocates a new block ('entry') to merge adjacent ranges and then stores it with mas_store_gfp(). When mas_store_gfp() fails, the new 'entry' remains allocated and is never freed, leaking memory. Free 'entry' on the failure path; on success continue freeing the replaced neighbor blocks ('lower', 'upper'). Signed-off-by: Kaushlendra Kumar Link: https://patch.msgid.link/20260105031820.260119-1-kaushlendra.kumar@intel.com Signed-off-by: Mark Brown --- drivers/base/regmap/regcache-maple.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regcache-maple.c b/drivers/base/regmap/regcache-maple.c index ca1c72b68f31..4134a77ae1d6 100644 --- a/drivers/base/regmap/regcache-maple.c +++ b/drivers/base/regmap/regcache-maple.c @@ -95,12 +95,13 @@ static int regcache_maple_write(struct regmap *map, unsigned int reg, mas_unlock(&mas); - if (ret == 0) { - kfree(lower); - kfree(upper); + if (ret) { + kfree(entry); + return ret; } - - return ret; + kfree(lower); + kfree(upper); + return 0; } static int regcache_maple_drop(struct regmap *map, unsigned int min, -- cgit v1.2.3 From 4b58aac989c1e3fafb1c68a733811859df388250 Mon Sep 17 00:00:00 2001 From: Cheng-Yu Lee Date: Fri, 9 Jan 2026 11:26:33 +0800 Subject: regmap: Fix race condition in hwspinlock irqsave routine Previously, the address of the shared member '&map->spinlock_flags' was passed directly to 'hwspin_lock_timeout_irqsave'. This creates a race condition where multiple contexts contending for the lock could overwrite the shared flags variable, potentially corrupting the state for the current lock owner. Fix this by using a local stack variable 'flags' to store the IRQ state temporarily. Fixes: 8698b9364710 ("regmap: Add hardware spinlock support") Signed-off-by: Cheng-Yu Lee Co-developed-by: Yu-Chun Lin Signed-off-by: Yu-Chun Lin Link: https://patch.msgid.link/20260109032633.8732-1-eleanor.lin@realtek.com Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index ce9be3989a21..ae2215d4e61c 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -408,9 +408,11 @@ static void regmap_lock_hwlock_irq(void *__map) static void regmap_lock_hwlock_irqsave(void *__map) { struct regmap *map = __map; + unsigned long flags = 0; hwspin_lock_timeout_irqsave(map->hwlock, UINT_MAX, - &map->spinlock_flags); + &flags); + map->spinlock_flags = flags; } static void regmap_unlock_hwlock(void *__map) -- cgit v1.2.3 From a995fe1a3aa78b7d06cc1cc7b6b8436c5e93b07f Mon Sep 17 00:00:00 2001 From: Danilo Krummrich Date: Wed, 7 Jan 2026 11:35:05 +0100 Subject: rust: driver: drop device private data post unbind Currently, the driver's device private data is allocated and initialized from driver core code called from bus abstractions after the driver's probe() callback returned the corresponding initializer. Similarly, the driver's device private data is dropped within the remove() callback of bus abstractions after calling the remove() callback of the corresponding driver. However, commit 6f61a2637abe ("rust: device: introduce Device::drvdata()") introduced an accessor for the driver's device private data for a Device, i.e. a device that is currently bound to a driver. Obviously, this is in conflict with dropping the driver's device private data in remove(), since a device can not be considered to be fully unbound after remove() has finished: We also have to consider registrations guarded by devres - such as IRQ or class device registrations - which are torn down after remove() in devres_release_all(). Thus, it can happen that, for instance, a class device or IRQ callback still calls Device::drvdata(), which then runs concurrently to remove() (which sets dev->driver_data to NULL and drops the driver's device private data), before devres_release_all() started to tear down the corresponding registration. This is because devres guarded registrations can, as expected, access the corresponding Device that defines their scope. In C it simply is the driver's responsibility to ensure that its device private data is freed after e.g. an IRQ registration is unregistered. Typically, C drivers achieve this by allocating their device private data with e.g. devm_kzalloc() before doing anything else, i.e. before e.g. registering an IRQ with devm_request_threaded_irq(), relying on the reverse order cleanup of devres. Technically, we could do something similar in Rust. However, the resulting code would be pretty messy: In Rust we have to differentiate between allocated but uninitialized memory and initialized memory in the type system. Thus, we would need to somehow keep track of whether the driver's device private data object has been initialized (i.e. probe() was successful and returned a valid initializer for this memory) and conditionally call the destructor of the corresponding object when it is freed. This is because we'd need to allocate and register the memory of the driver's device private data *before* it is initialized by the initializer returned by the driver's probe() callback, because the driver could already register devres guarded registrations within probe() outside of the driver's device private data initializer. Luckily there is a much simpler solution: Instead of dropping the driver's device private data at the end of remove(), we just drop it after the device has been fully unbound, i.e. after all devres callbacks have been processed. For this, we introduce a new post_unbind() callback private to the driver-core, i.e. the callback is neither exposed to drivers, nor to bus abstractions. This way, the driver-core code can simply continue to conditionally allocate the memory for the driver's device private data when the driver's initializer is returned from probe() - no change needed - and drop it when the driver-core code receives the post_unbind() callback. Closes: https://lore.kernel.org/all/DEZMS6Y4A7XE.XE7EUBT5SJFJ@kernel.org/ Fixes: 6f61a2637abe ("rust: device: introduce Device::drvdata()") Acked-by: Alice Ryhl Acked-by: Greg Kroah-Hartman Acked-by: Igor Korotin Link: https://patch.msgid.link/20260107103511.570525-7-dakr@kernel.org [ Remove #ifdef CONFIG_RUST, rename post_unbind() to post_unbind_rust(). - Danilo] Signed-off-by: Danilo Krummrich --- drivers/base/dd.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 349f31bedfa1..bea8da5f8a3a 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -548,6 +548,8 @@ static DEVICE_ATTR_RW(state_synced); static void device_unbind_cleanup(struct device *dev) { devres_release_all(dev); + if (dev->driver->p_cb.post_unbind_rust) + dev->driver->p_cb.post_unbind_rust(dev); arch_teardown_dma_ops(dev); kfree(dev->dma_range_map); dev->dma_range_map = NULL; -- cgit v1.2.3