Kuppuswamy Sathyanarayanan 8d1c12b12e drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish ... [ 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 <sathyanarayanan.kuppuswamy@linux.intel.com> Link: https://lore.kernel.org/r/20200408214003.3356-1-sathyanarayanan.kuppuswamy@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-03-16 16:30:13 +08:00
..
firmware_loader	firmware: fix a double abort case with fw_load_sysfs_fallback	2021-03-16 16:25:58 +08:00
power	PM: sleep: core: Switch back to async_schedule_dev()	2021-03-16 16:27:11 +08:00
regmap	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
test	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Makefile	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
arch_topology.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
attribute_container.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
base.h	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
bus.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
cacheinfo.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
class.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
component.c	component: Silence bind error on -EPROBE_DEFER	2021-03-16 16:28:10 +08:00
container.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
core.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
cpu.c	x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation	2021-03-16 16:28:53 +08:00
dd.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
devcon.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
devcoredump.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
devres.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
devtmpfs.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
driver.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
firmware.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
hypervisor.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
init.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
isa.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
map.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
memory.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
module.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
node.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
pinctrl.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
platform-msi.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
platform.c	drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish	2021-03-16 16:30:13 +08:00
property.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
soc.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
swnode.c	Revert "software node: Simplify software_node_release() function"	2021-03-16 16:27:29 +08:00
syscore.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
topology.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
transport_class.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00