user/sven/linux.git/drivers/base, branch v4.14.186

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

2020-06-25T13:41:51Z

[ 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

x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation

2020-06-11T07:23:01Z

commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Reviewed-by: Tony Luck Reviewed-by: Pawan Gupta Reviewed-by: Josh Poimboeuf Tested-by: Neelima Krishnan Signed-off-by: Greg Kroah-Hartman

component: Silence bind error on -EPROBE_DEFER

2020-05-27T14:42:57Z

[ Upstream commit 7706b0a76a9697021e2bf395f3f065c18f51043d ] If a component fails to bind due to -EPROBE_DEFER we should not log an error as this is not a real failure. Fixes messages like: vc4-drm soc:gpu: failed to bind 3f902000.hdmi (ops vc4_hdmi_ops): -517 vc4-drm soc:gpu: master bind failed: -517 Signed-off-by: James Hilliard Link: https://lore.kernel.org/r/20200411190241.89404-1-james.hilliard1@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

arch_topology: Fix section miss match warning due to free_raw_capacity()

2020-04-24T06:01:03Z

[ Upstream commit 82d8ba717ccb54dd803624db044f351b2a54d000 ] Remove the __init annotation from free_raw_capacity() to avoid the following warning. The function init_cpu_capacity_callback() references the function __init free_raw_capacity(). WARNING: vmlinux.o(.text+0x425cc0): Section mismatch in reference from the function init_cpu_capacity_callback() to the function .init.text:free_raw_capacity(). Signed-off-by: Prasad Sodagudi Acked-by: Viresh Kumar Signed-off-by: Greg Kroah-Hartman Signed-off-by: Lee Jones Signed-off-by: Greg Kroah-Hartman

driver core: platform: fix u32 greater or equal to zero comparison

2020-02-28T15:36:06Z

[ Upstream commit 0707cfa5c3ef58effb143db9db6d6e20503f9dec ] Currently the check that a u32 variable i is >= 0 is always true because the unsigned variable will never be negative, causing the loop to run forever. Fix this by changing the pre-decrement check to a zero check on i followed by a decrement of i. Addresses-Coverity: ("Unsigned compared against 0") Fixes: 39cc539f90d0 ("driver core: platform: Prevent resouce overflow from causing infinite loops") Signed-off-by: Colin Ian King Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20200116175758.88396-1-colin.king@canonical.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

driver core: Print device when resources present in really_probe()

2020-02-28T15:36:04Z

[ Upstream commit 7c35e699c88bd60734277b26962783c60e04b494 ] If a device already has devres items attached before probing, a warning backtrace is printed. However, this backtrace does not reveal the offending device, leaving the user uninformed. Furthermore, using WARN_ON() causes systems with panic-on-warn to reboot. Fix this by replacing the WARN_ON() by a dev_crit() message. Abort probing the device, to prevent doing more damage to the device's resources. Signed-off-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20191206132219.28908-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

driver core: platform: Prevent resouce overflow from causing infinite loops

2020-02-28T15:36:03Z

[ Upstream commit 39cc539f90d035a293240c9443af50be55ee81b8 ] num_resources in the platform_device struct is declared as a u32. The for loops that iterate over num_resources use an int as the counter, which can cause infinite loops on architectures with smaller ints. Change the loop counters to u32. Signed-off-by: Simon Schwartz Link: https://lore.kernel.org/r/2201ce63a2a171ffd2ed14e867875316efcf71db.camel@theschwartz.xyz Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

PM: core: Fix handling of devices deleted during system-wide resume

2020-02-14T21:32:13Z

commit 0552e05fdfea191a2cf3a0abd33574b5ef9ca818 upstream. If a device is deleted by one of its system-wide resume callbacks (for example, because it does not appear to be present or accessible any more) along with its children, the resume of the children may continue leading to use-after-free errors and other issues (potentially). Namely, if the device's children are resumed asynchronously, their resume may have been scheduled already before the device's callback runs and so the device may be deleted while dpm_wait_for_superior() is being executed for them. The memory taken up by the parent device object may be freed then while dpm_wait() is waiting for the parent's resume callback to complete, which leads to a use-after-free. Moreover, the resume of the children is really not expected to continue after they have been unregistered, so it must be terminated right away in that case. To address this problem, modify dpm_wait_for_superior() to check if the target device is still there in the system-wide PM list of devices and if so, to increment its parent's reference counter, both under dpm_list_mtx which prevents device_del() running for the child from dropping the parent's reference counter prematurely. If the device is not present in the system-wide PM list of devices any more, the resume of it cannot continue, so check that again after dpm_wait() returns, which means that the parent's callback has been completed, and pass the result of that check to the caller of dpm_wait_for_superior() to allow it to abort the device's resume if it is not there any more. Link: https://lore.kernel.org/linux-pm/1579568452-27253-1-git-send-email-chanho.min@lge.com Reported-by: Chanho Min Cc: All applicable Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

PM: sleep: Fix possible overflow in pm_system_cancel_wakeup()

2020-01-27T13:46:40Z

[ Upstream commit 2933954b71f10d392764f95eec0f0aa2d103054b ] It is not actually guaranteed that pm_abort_suspend will be nonzero when pm_system_cancel_wakeup() is called which may lead to subtle issues, so make it use atomic_dec_if_positive() instead of atomic_dec() for the safety sake. Fixes: 33e4f80ee69b ("ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle") Signed-off-by: Rafael J. Wysocki Acked-by: Thomas Gleixner Signed-off-by: Sasha Levin

driver core: Do not resume suppliers under device_links_write_lock()

2020-01-27T13:46:15Z

[ Upstream commit 5db25c9eb893df8f6b93c1d97b8006d768e1b6f5 ] It is incorrect to call pm_runtime_get_sync() under device_links_write_lock(), because it may end up trying to take device_links_read_lock() while resuming the target device and that will deadlock in the non-SRCU case, so avoid that by resuming the supplier device in device_link_add() before calling device_links_write_lock(). Fixes: 21d5c57b3726 ("PM / runtime: Use device links") Fixes: baa8809f6097 ("PM / runtime: Optimize the use of device links") Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin