kernel/linux.git/drivers/base, branch v4.4.239

driver core: Fix probe_count imbalance in really_probe()

2020-10-14T07:46:22+00:00

commit b292b50b0efcc7095d8bf15505fba6909bb35dce upstream. syzbot is reporting hung task in wait_for_device_probe() [1]. At least, we always need to decrement probe_count if we incremented probe_count in really_probe(). However, since I can't find "Resources present before probing" message in the console log, both "this message simply flowed off" and "syzbot is not hitting this path" will be possible. Therefore, while we are at it, let's also prepare for concurrent wait_for_device_probe() calls by replacing wake_up() with wake_up_all(). [1] https://syzkaller.appspot.com/bug?id=25c833f1983c9c1d512f4ff860dd0d7f5a2e2c0f Reported-by: syzbot Fixes: 7c35e699c88bd607 ("driver core: Print device when resources present in really_probe()") Cc: Geert Uytterhoeven Signed-off-by: Tetsuo Handa Cc: stable Link: https://lore.kernel.org/r/20200713021254.3444-1-penguin-kernel@I-love.SAKURA.ne.jp [iwamatsu: Drop patch for deferred_probe_timeout_work_func()] Signed-off-by: Nobuhiro Iwamatsu (CIP) Signed-off-by: Greg Kroah-Hartman

device property: Fix the secondary firmware node handling in set_primary_fwnode()

2020-09-03T09:19:27+00:00

commit c15e1bdda4365a5f17cdadf22bf1c1df13884a9e upstream. When the primary firmware node pointer is removed from a device (set to NULL) the secondary firmware node pointer, when it exists, is made the primary node for the device. However, the secondary firmware node pointer of the original primary firmware node is never cleared (set to NULL). To avoid situation where the secondary firmware node pointer is pointing to a non-existing object, clearing it properly when the primary node is removed from a device in set_primary_fwnode(). Fixes: 97badf873ab6 ("device property: Make it possible to use secondary firmware nodes") Cc: All applicable Signed-off-by: Heikki Krogerus Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM: sleep: core: Fix the handling of pending runtime resume requests

2020-09-03T09:19:27+00:00

commit e3eb6e8fba65094328b8dca635d00de74ba75b45 upstream. It has been reported that system-wide suspend may be aborted in the absence of any wakeup events due to unforseen interactions of it with the runtume PM framework. One failing scenario is when there are multiple devices sharing an ACPI power resource and runtime-resume needs to be carried out for one of them during system-wide suspend (for example, because it needs to be reconfigured before the whole system goes to sleep). In that case, the runtime-resume of that device involves turning the ACPI power resource "on" which in turn causes runtime-resume requests to be queued up for all of the other devices sharing it. Those requests go to the runtime PM workqueue which is frozen during system-wide suspend, so they are not actually taken care of until the resume of the whole system, but the pm_runtime_barrier() call in __device_suspend() sees them and triggers system wakeup events for them which then cause the system-wide suspend to be aborted if wakeup source objects are in active use. Of course, the logic that leads to triggering those wakeup events is questionable in the first place, because clearly there are cases in which a pending runtime resume request for a device is not connected to any real wakeup events in any way (like the one above). Moreover, it is racy, because the device may be resuming already by the time the pm_runtime_barrier() runs and so if the driver doesn't take care of signaling the wakeup event as appropriate, it will be lost. However, if the driver does take care of that, the extra pm_wakeup_event() call in the core is redundant. Accordingly, drop the conditional pm_wakeup_event() call fron __device_suspend() and make the latter call pm_runtime_barrier() alone. Also modify the comment next to that call to reflect the new code and extend it to mention the need to avoid unwanted interactions between runtime PM and system-wide device suspend callbacks. Fixes: 1e2ef05bb8cf8 ("PM: Limit race conditions between runtime PM and system sleep (v2)") Signed-off-by: Rafael J. Wysocki Acked-by: Alan Stern Reported-by: Utkarsh H Patel Tested-by: Utkarsh H Patel Tested-by: Pengfei Xu Cc: All applicable Signed-off-by: Greg Kroah-Hartman

regmap: debugfs: check count when read regmap file

2020-07-31T14:43:16+00:00

commit 74edd08a4fbf51d65fd8f4c7d8289cd0f392bd91 upstream. When executing the following command, we met kernel dump. dmesg -c > /dev/null; cd /sys; for i in `ls /sys/kernel/debug/regmap/* -d`; do echo "Checking regmap in $i"; cat $i/registers; done && grep -ri "0x02d0" *; It is because the count value is too big, and kmalloc fails. So add an upper bound check to allow max size `PAGE_SIZE << (MAX_ORDER - 1)`. Signed-off-by: Peng Fan Link: https://lore.kernel.org/r/1584064687-12964-1-git-send-email-peng.fan@nxp.com Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman

regmap: dev_get_regmap_match(): fix string comparison

2020-07-31T14:43:13+00:00

[ Upstream commit e84861fec32dee8a2e62bbaa52cded6b05a2a456 ] This function is used by dev_get_regmap() to retrieve a regmap for the specified device. If the device has more than one regmap, the name parameter can be used to specify one. The code here uses a pointer comparison to check for equal strings. This however will probably always fail, as the regmap->name is allocated via kstrdup_const() from the regmap's config->name. Fix this by using strcmp() instead. Signed-off-by: Marc Kleine-Budde Link: https://lore.kernel.org/r/20200703103315.267996-1-mkl@pengutronix.de Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

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

2020-06-30T00:07:51+00:00

[ 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

2020-06-11T07:21:40+00:00

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

isa: Call isa_bus_init before dependent ISA bus drivers register

2020-05-10T08:26:03+00:00

commit 32a5a0c047343b11f581f663a2309cf43d13466f upstream. The isa_bus_init function must be called before drivers which utilize the ISA bus driver are registered. A race condition for initilization exists if device_initcall is used (the isa_bus_init callback is placed in the same initcall level as dependent drivers which use module_init). This patch ensures that isa_bus_init is called first by utilizing postcore_initcall in favor of device_initcall. Fixes: a5117ba7da37 ("[PATCH] Driver model: add ISA bus") Cc: Rene Herman Signed-off-by: William Breathitt Gray Signed-off-by: Greg Kroah-Hartman

firmware: actually return NULL on failed request_firmware_nowait()

2020-05-10T08:25:54+00:00

commit 715780ae4bb76d6fd2f20eb78e2a9ba9769a6cdc upstream. The kerneldoc for request_firmware_nowait() says that it may call the provided cont() callback with @fw == NULL, if the firmware request fails. However, this is not the case when called with an empty string (""). This case is short-circuited by the 'name[0] == '\0'' check introduced in commit 471b095dfe0d ("firmware_class: make sure fw requests contain a name"), so _request_firmware() never gets to set the fw to NULL. Noticed while using the new 'trigger_async_request' testing hook: # printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request [10553.726178] test_firmware: loading '' [10553.729859] test_firmware: loaded: 995209091 # printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request [10733.676184] test_firmware: loading '' [10733.679855] Unable to handle kernel NULL pointer dereference at virtual address 00000004 [10733.687951] pgd = ec188000 [10733.690655] [00000004] *pgd=00000000 [10733.694240] Internal error: Oops: 5 [#1] SMP ARM [10733.698847] Modules linked in: btmrvl_sdio btmrvl bluetooth sbs_battery nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables asix usbnet mwifiex_sdio mwifiex cfg80211 jitterentropy_rng drbg joydev snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device ppp_async ppp_generic slhc tun [10733.725670] CPU: 0 PID: 6600 Comm: bash Not tainted 4.4.0-rc4-00351-g63d0877 #178 [10733.733137] Hardware name: Rockchip (Device Tree) [10733.737831] task: ed24f6c0 ti: ee322000 task.ti: ee322000 [10733.743222] PC is at do_raw_spin_lock+0x18/0x1a0 [10733.747831] LR is at _raw_spin_lock+0x18/0x1c [10733.752180] pc : [] lr : [] psr: a00d0013 [10733.752180] sp : ee323df8 ip : ee323e20 fp : ee323e1c [10733.763634] r10: 00000051 r9 : b6f18000 r8 : ee323f80 [10733.768847] r7 : c089cebc r6 : 00000001 r5 : 00000000 r4 : ec0e6000 [10733.775360] r3 : dead4ead r2 : c06bd140 r1 : eef913b4 r0 : 00000000 [10733.781874] Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none [10733.788995] Control: 10c5387d Table: 2c18806a DAC: 00000051 [10733.794728] Process bash (pid: 6600, stack limit = 0xee322218) [10733.800549] Stack: (0xee323df8 to 0xee324000) [10733.804896] 3de0: ec0e6000 00000000 [10733.813059] 3e00: 00000001 c089cebc ee323f80 b6f18000 ee323e2c ee323e20 c054c204 c0065394 [10733.821221] 3e20: ee323e44 ee323e30 c02fec60 c054c1f8 ec0e7ec0 ec3fcfc0 ee323e5c ee323e48 [10733.829384] 3e40: c02fed08 c02fec48 c07dbf74 eeb05a00 ee323e8c ee323e60 c0253828 c02fecac [10733.837547] 3e60: 00000001 c0116950 ee323eac ee323e78 00000001 ec3fce00 ed2d9700 ed2d970c [10733.845710] 3e80: ee323e9c ee323e90 c02e873c c02537d4 ee323eac ee323ea0 c017bd40 c02e8720 [10733.853873] 3ea0: ee323ee4 ee323eb0 c017b250 c017bd00 00000000 00000000 f3e47a54 ec128b00 [10733.862035] 3ec0: c017b10c ee323f80 00000001 c000f504 ee322000 00000000 ee323f4c ee323ee8 [10733.870197] 3ee0: c011b71c c017b118 ee323fb0 c011bc90 becfa8d9 00000001 ec128b00 00000001 [10733.878359] 3f00: b6f18000 ee323f80 ee323f4c ee323f18 c011bc90 c0063950 ee323f3c ee323f28 [10733.886522] 3f20: c0063950 c0549138 00000001 ec128b00 00000001 ec128b00 b6f18000 ee323f80 [10733.894684] 3f40: ee323f7c ee323f50 c011bed8 c011b6ec c0135fb8 c0135f24 ec128b00 ec128b00 [10733.902847] 3f60: 00000001 b6f18000 c000f504 ee322000 ee323fa4 ee323f80 c011c664 c011be24 [10733.911009] 3f80: 00000000 00000000 00000001 b6f18000 b6e79be0 00000004 00000000 ee323fa8 [10733.919172] 3fa0: c000f340 c011c618 00000001 b6f18000 00000001 b6f18000 00000001 00000000 [10733.927334] 3fc0: 00000001 b6f18000 b6e79be0 00000004 00000001 00000001 8068a3f1 b6e79c84 [10733.935496] 3fe0: 00000000 becfa7dc b6de194d b6e20246 400d0030 00000001 7a4536e8 49bda390 [10733.943664] [] (do_raw_spin_lock) from [] (_raw_spin_lock+0x18/0x1c) [10733.951743] [] (_raw_spin_lock) from [] (fw_free_buf+0x24/0x64) [10733.959388] [] (fw_free_buf) from [] (release_firmware+0x68/0x74) [10733.967207] [] (release_firmware) from [] (trigger_async_request_store+0x60/0x124) [10733.976501] [] (trigger_async_request_store) from [] (dev_attr_store+0x28/0x34) [10733.985533] [] (dev_attr_store) from [] (sysfs_kf_write+0x4c/0x58) [10733.993437] [] (sysfs_kf_write) from [] (kernfs_fop_write+0x144/0x1a8) [10734.001689] [] (kernfs_fop_write) from [] (__vfs_write+0x3c/0xe4) After this patch: # printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request [ 32.126322] test_firmware: loading '' [ 32.129995] test_firmware: failed to async load firmware -bash: printf: write error: No such device Fixes: 471b095dfe0d ("firmware_class: make sure fw requests contain a name") Signed-off-by: Brian Norris Acked-by: Ming Lei Acked-by: Kees Cook Signed-off-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman

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

2020-02-28T14:39:03+00:00

[ 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