user/sven/linux.git/drivers/base/platform.c, branch v4.4.271

drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish

2020-06-30T00:07:51Z

[ Upstream commit 388bcc6ecc609fca1b4920de7dc3806c98ec535e ] If platform bus driver registration is failed then, accessing platform bus spin lock (&drv->driver.bus->p->klist_drivers.k_lock) in __platform_driver_probe() without verifying the return value __platform_driver_register() can lead to NULL pointer exception. So check the return value before attempting the spin lock. One such example is below: For a custom usecase, I have intentionally failed the platform bus registration and I expected all the platform device/driver registrations to fail gracefully. But I came across this panic issue. [ 1.331067] BUG: kernel NULL pointer dereference, address: 00000000000000c8 [ 1.331118] #PF: supervisor write access in kernel mode [ 1.331163] #PF: error_code(0x0002) - not-present page [ 1.331208] PGD 0 P4D 0 [ 1.331233] Oops: 0002 [#1] PREEMPT SMP [ 1.331268] CPU: 3 PID: 1 Comm: swapper/0 Tainted: G W 5.6.0-00049-g670d35fb0144 #165 [ 1.331341] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 1.331406] RIP: 0010:_raw_spin_lock+0x15/0x30 [ 1.331588] RSP: 0000:ffffc9000001be70 EFLAGS: 00010246 [ 1.331632] RAX: 0000000000000000 RBX: 00000000000000c8 RCX: 0000000000000001 [ 1.331696] RDX: 0000000000000001 RSI: 0000000000000092 RDI: 0000000000000000 [ 1.331754] RBP: 00000000ffffffed R08: 0000000000000501 R09: 0000000000000001 [ 1.331817] R10: ffff88817abcc520 R11: 0000000000000670 R12: 00000000ffffffed [ 1.331881] R13: ffffffff82dbc268 R14: ffffffff832f070a R15: 0000000000000000 [ 1.331945] FS: 0000000000000000(0000) GS:ffff88817bd80000(0000) knlGS:0000000000000000 [ 1.332008] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.332062] CR2: 00000000000000c8 CR3: 000000000681e001 CR4: 00000000003606e0 [ 1.332126] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1.332189] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1.332252] Call Trace: [ 1.332281] __platform_driver_probe+0x92/0xee [ 1.332323] ? rtc_dev_init+0x2b/0x2b [ 1.332358] cmos_init+0x37/0x67 [ 1.332396] do_one_initcall+0x7d/0x168 [ 1.332428] kernel_init_freeable+0x16c/0x1c9 [ 1.332473] ? rest_init+0xc0/0xc0 [ 1.332508] kernel_init+0x5/0x100 [ 1.332543] ret_from_fork+0x1f/0x30 [ 1.332579] CR2: 00000000000000c8 [ 1.332616] ---[ end trace 3bd87f12e9010b87 ]--- [ 1.333549] note: swapper/0[1] exited with preempt_count 1 [ 1.333592] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 [ 1.333736] Kernel Offset: disabled Note, this can only be triggered if a driver errors out from this call, which should never happen. If it does, the driver needs to be fixed. Signed-off-by: Kuppuswamy Sathyanarayanan Link: https://lore.kernel.org/r/20200408214003.3356-1-sathyanarayanan.kuppuswamy@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

driver core: platform: Don't read past the end of "driver_override" buffer

2017-10-12T09:27:32Z

commit bf563b01c2895a4bfd1a29cc5abc67fe706ecffd upstream. When printing the driver_override parameter when it is 4095 and 4094 bytes long, the printing code would access invalid memory because we need count+1 bytes for printing. Reject driver_override values of these lengths in driver_override_store(). This is in close analogy to commit 4efe874aace5 ("PCI: Don't read past the end of sysfs "driver_override" buffer") from Sasha Levin. Fixes: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'") Signed-off-by: Nicolai Stange Signed-off-by: Greg Kroah-Hartman

driver core: platform: fix race condition with driver_override

2017-07-15T09:57:44Z

commit 6265539776a0810b7ce6398c27866ddb9c6bd154 upstream. The driver_override implementation is susceptible to race condition when different threads are reading vs storing a different driver override. Add locking to avoid race condition. Fixes: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'") Cc: stable@vger.kernel.org Signed-off-by: Adrian Salido Signed-off-by: Greg Kroah-Hartman

platform: don't return 0 from platform_get_irq[_byname]() on error

2016-10-28T07:01:26Z

commit e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af upstream. of_irq_get[_byname]() return 0 iff irq_create_of_mapping() call fails. Returning both error code and 0 on failure is a sign of a misdesigned API, it makes the failure check unnecessarily complex and error prone. We should rely on the platform IRQ resource in this case, not return 0, especially as 0 can be a valid IRQ resource too... Fixes: aff008ad813c ("platform_get_irq: Revert to platform_get_resource if of_irq_get fails") Signed-off-by: Sergei Shtylyov Signed-off-by: Greg Kroah-Hartman

base/platform: Fix platform drivers with no probe callback

2016-02-17T20:30:55Z

commit 25cad69f21f5532d99e2ee73c8ab6512bcab614c upstream. Since b8b2c7d845d5, platform_drv_probe() is called for all platform devices. If drv->probe is NULL, and dev_pm_domain_attach() fails, platform_drv_probe() will return the error code from dev_pm_domain_attach(). This causes real_probe() to enter the "probe_failed" path and set dev->driver to NULL. Before b8b2c7d845d5, real_probe() would assume success if both dev->bus->probe and drv->probe were missing. As a result, a device and driver could be "bound" together just by matching their names; this doesn't work any more after b8b2c7d845d5. This may cause problems later for certain usage of platform_driver_register() and platform_device_register_simple(). I observed a panic while loading the tpm_tis driver with parameter "force=1" (i.e. registering tpm_tis as a platform driver), because tpm_tis_init's assumption that the device returned by platform_device_register_simple() was bound didn't hold any more (tpmm_chip_alloc() dereferences chip->pdev->driver, causing panic). This patch restores the previous (4.3.0 and earlier) behavior of platform_drv_probe() in the case when the associated platform driver has no "probe" function. Fixes: b8b2c7d845d5 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally") Signed-off-by: Martin Wilck Cc: Martin Fuzzey Acked-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

driver-core: platform: Provide helpers for multi-driver modules

2015-10-05T04:02:40Z

Some modules register several sub-drivers. Provide a helper that makes it easy to register and unregister a list of sub-drivers, as well as unwind properly on error. Signed-off-by: Thierry Reding Signed-off-by: Greg Kroah-Hartman

base/platform: assert that dev_pm_domain callbacks are called unconditionally

2015-10-04T18:42:22Z

When a platform driver doesn't provide a .remove callback the function platform_drv_remove isn't called and so the call to dev_pm_domain_attach called at probe time isn't paired by dev_pm_domain_detach at remove time. To fix this (and similar issues if different callbacks are missing) hook up the driver callbacks unconditionally and make them aware that the platform callbacks might be missing. Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman

drivercore: Fix unregistration path of platform devices

2015-08-25T16:29:57Z

The unregister path of platform_device is broken. On registration, it will register all resources with either a parent already set, or type==IORESOURCE_{IO,MEM}. However, on unregister it will release everything with type==IORESOURCE_{IO,MEM}, but ignore the others. There are also cases where resources don't get registered in the first place, like with devices created by of_platform_populate()*. Fix the unregister path to be symmetrical with the register path by checking the parent pointer instead of the type field to decide which resources to unregister. This is safe because the upshot of the registration path algorithm is that registered resources have a parent pointer, and non-registered resources do not. * It can be argued that of_platform_populate() should be registering it's resources, and they argument has some merit. However, there are quite a few platforms that end up broken if we try to do that due to overlapping resources in the device tree. Until that is fixed, we need to solve the immediate problem. Cc: Pantelis Antoniou Cc: Wolfram Sang Cc: Rob Herring Cc: Greg Kroah-Hartman Cc: Ricardo Ribalda Delgado Signed-off-by: Grant Likely Tested-by: Ricardo Ribalda Delgado Tested-by: Wolfram Sang Cc: stable@vger.kernel.org Signed-off-by: Rob Herring

Revert "base/platform: Only insert MEM and IO resources"

2015-06-10T15:38:29Z

This reverts commit 36d4b29260753ad78b1ce4363145332c02519adc as it breaks working machines. Cc: Rob Herring Cc: Ricardo Ribalda Delgado Signed-off-by: Greg Kroah-Hartman

Revert "base/platform: Continue on insert_resource() error"

2015-06-10T15:38:02Z

This reverts commit e50e69d1ac4232af0b6890f16929bf5ceee81538 as it breaks working machines. Cc: Rob Herring Cc: Ricardo Ribalda Delgado Signed-off-by: Greg Kroah-Hartman