kernel/linux.git/drivers/pps/clients, branch v6.6.132

pps: clients: gpio: fix interrupt handling order in remove path

2025-08-28T14:28:18+00:00

[ Upstream commit 6bca1e955830808dc90e0506b2951b4256b81bbb ] The interrupt handler in pps_gpio_probe() is registered after calling pps_register_source() using devm_request_irq(). However, in the corresponding remove function, pps_unregister_source() is called before the IRQ is freed, since devm-managed resources are released after the remove function completes. This creates a potential race condition where an interrupt may occur after the PPS source is unregistered but before the handler is removed, possibly leading to a kernel panic. To prevent this, switch from devm-managed IRQ registration to manual management by using request_irq() and calling free_irq() explicitly in the remove path before unregistering the PPS source. This ensures the interrupt handler is safely removed before deactivating the PPS source. Signed-off-by: Eliav Farber Link: https://lore.kernel.org/r/20250527053355.37185-1-farbere@amazon.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

pps: Fix a use-after-free

2025-02-08T08:52:38+00:00

commit c79a39dc8d060b9e64e8b0fa9d245d44befeefbe upstream. On a board running ntpd and gpsd, I'm seeing a consistent use-after-free in sys_exit() from gpsd when rebooting: pps pps1: removed ------------[ cut here ]------------ kobject: '(null)' (00000000db4bec24): is not initialized, yet kobject_put() is being called. WARNING: CPU: 2 PID: 440 at lib/kobject.c:734 kobject_put+0x120/0x150 CPU: 2 UID: 299 PID: 440 Comm: gpsd Not tainted 6.11.0-rc6-00308-gb31c44928842 #1 Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : kobject_put+0x120/0x150 lr : kobject_put+0x120/0x150 sp : ffffffc0803d3ae0 x29: ffffffc0803d3ae0 x28: ffffff8042dc9738 x27: 0000000000000001 x26: 0000000000000000 x25: ffffff8042dc9040 x24: ffffff8042dc9440 x23: ffffff80402a4620 x22: ffffff8042ef4bd0 x21: ffffff80405cb600 x20: 000000000008001b x19: ffffff8040b3b6e0 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 696e6920746f6e20 x14: 7369203a29343263 x13: 205d303434542020 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: kobject_put+0x120/0x150 cdev_put+0x20/0x3c __fput+0x2c4/0x2d8 ____fput+0x1c/0x38 task_work_run+0x70/0xfc do_exit+0x2a0/0x924 do_group_exit+0x34/0x90 get_signal+0x7fc/0x8c0 do_signal+0x128/0x13b4 do_notify_resume+0xdc/0x160 el0_svc+0xd4/0xf8 el0t_64_sync_handler+0x140/0x14c el0t_64_sync+0x190/0x194 ---[ end trace 0000000000000000 ]--- ...followed by more symptoms of corruption, with similar stacks: refcount_t: underflow; use-after-free. kernel BUG at lib/list_debug.c:62! Kernel panic - not syncing: Oops - BUG: Fatal exception This happens because pps_device_destruct() frees the pps_device with the embedded cdev immediately after calling cdev_del(), but, as the comment above cdev_del() notes, fops for previously opened cdevs are still callable even after cdev_del() returns. I think this bug has always been there: I can't explain why it suddenly started happening every time I reboot this particular board. In commit d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source."), George Spelvin suggested removing the embedded cdev. That seems like the simplest way to fix this, so I've implemented his suggestion, using __register_chrdev() with pps_idr becoming the source of truth for which minor corresponds to which device. But now that pps_idr defines userspace visibility instead of cdev_add(), we need to be sure the pps->dev refcount can't reach zero while userspace can still find it again. So, the idr_remove() call moves to pps_unregister_cdev(), and pps_idr now holds a reference to pps->dev. pps_core: source serial1 got cdev (251:1) <...> pps pps1: removed pps_core: unregistering pps1 pps_core: deallocating pps1 Fixes: d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source.") Cc: stable@vger.kernel.org Signed-off-by: Calvin Owens Reviewed-by: Michal Schmidt Link: https://lore.kernel.org/r/a17975fd5ae99385791929e563f72564edbcf28f.1731383727.git.calvin@wbinvd.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

pps: add an error check in parport_attach

2024-10-04T14:29:58+00:00

[ Upstream commit 62c5a01a5711c8e4be8ae7b6f0db663094615d48 ] In parport_attach, the return value of ida_alloc is unchecked, witch leads to the use of an invalid index value. To address this issue, index should be checked. When the index value is abnormal, the device should be freed. Found by code review, compile tested only. Cc: stable@vger.kernel.org Fixes: fb56d97df70e ("pps: client: use new parport device model") Signed-off-by: Ma Ke Acked-by: Rodolfo Giometti Link: https://lore.kernel.org/r/20240828131814.3034338-1-make24@iscas.ac.cn Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

pps: remove usage of the deprecated ida_simple_xx() API

2024-10-04T14:29:58+00:00

[ Upstream commit 55dbc5b5174d0e7d1fa397d05aa4cb145e8b887e ] ida_alloc() and ida_free() should be preferred to the deprecated ida_simple_get() and ida_simple_remove(). This is less verbose. Link: https://lkml.kernel.org/r/9f681747d446b874952a892491387d79ffe565a9.1713089394.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christophe JAILLET Cc: Rodolfo Giometti Cc: Greg Kroah-Hartman Signed-off-by: Andrew Morton Stable-dep-of: 62c5a01a5711 ("pps: add an error check in parport_attach") Signed-off-by: Sasha Levin

tty/serial: Make ->dcd_change()+uart_handle_dcd_change() status bool active

2023-01-19T15:04:35+00:00

Convert status parameter for ->dcd_change() and uart_handle_dcd_change() to bool which matches to how the parameter is used. Rename status to active to better describe what the parameter means. Acked-by: Rodolfo Giometti Reviewed-by: Jiri Slaby Signed-off-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20230117090358.4796-9-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman

pps: clients: gpio: Propagate return value from pps_gpio_probe

2022-02-04T14:33:42+00:00

If the pps-gpio driver was probed prior to the GPIO device it uses, the devm_gpiod_get call returned an -EPROBE_DEFER error, but pps_gpio_probe replaced that error code with -EINVAL, causing the pps-gpio probe to fail and not be retried later. Propagate the error return value so that deferred probe works properly. Fixes: 161520451dfa (pps: new client driver using GPIO) Reviewed-by: Andy Shevchenko Acked-by: Rodolfo Giometti Signed-off-by: Robert Hancock Signed-off-by: Rodolfo Giometti Link: https://lore.kernel.org/r/20220112205214.2060954-1-robert.hancock@calian.com Signed-off-by: Greg Kroah-Hartman

pps: clients: parport: Switch to use module_parport_driver()

2021-07-29T15:29:14+00:00

Switch to use module_parport_driver() to reduce boilerplate code. Acked-by: Rodolfo Giometti Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20210607153729.58623-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman

tty: no checking of tty_unregister_ldisc

2021-05-13T14:57:17+00:00

tty_unregister_ldisc now returns 0 = success. No need to check the return value. In fact, the users only warned if an error occured and didn't do anything useful anyway -- the ldisc module was unloaded in any case. Signed-off-by: Jiri Slaby Cc: William Hubbs Cc: Chris Brannon Cc: Kirk Reiser Cc: Samuel Thibault Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Cc: Arnd Bergmann Cc: Wolfgang Grandegger Cc: Marc Kleine-Budde Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Andreas Koensgen Cc: Paul Mackerras Cc: Rodolfo Giometti Cc: Peter Ujfalusi Cc: Liam Girdwood Cc: Mark Brown Cc: Jaroslav Kysela Cc: Takashi Iwai Link: https://lore.kernel.org/r/20210505091928.22010-19-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: make tty_ldisc_ops a param in tty_unregister_ldisc

2021-05-13T14:57:16+00:00

Make tty_unregister_ldisc symmetric to tty_register_ldisc by accepting struct tty_ldisc_ops as a parameter instead of ldisc number. This avoids checking of the ldisc number bounds in tty_unregister_ldisc. Signed-off-by: Jiri Slaby Cc: William Hubbs Cc: Chris Brannon Cc: Kirk Reiser Cc: Samuel Thibault Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Cc: Dmitry Torokhov Cc: Arnd Bergmann Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Wolfgang Grandegger Cc: Marc Kleine-Budde Cc: Andreas Koensgen Cc: Paul Mackerras Cc: Rodolfo Giometti Cc: Peter Ujfalusi Cc: Liam Girdwood Cc: Mark Brown Cc: Jaroslav Kysela Cc: Takashi Iwai Link: https://lore.kernel.org/r/20210505091928.22010-17-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman

tty: set tty_ldisc_ops::num statically

2021-05-13T14:57:16+00:00

There is no reason to pass the ldisc number to tty_register_ldisc separately. Just set it in the already defined tty_ldisc_ops in all the ldiscs. This simplifies tty_register_ldisc a bit too (no need to set the num member there). Signed-off-by: Jiri Slaby Cc: William Hubbs Cc: Chris Brannon Cc: Kirk Reiser Cc: Samuel Thibault Cc: Marcel Holtmann Cc: Johan Hedberg Cc: Luiz Augusto von Dentz Cc: Dmitry Torokhov Cc: Arnd Bergmann Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Wolfgang Grandegger Cc: Marc Kleine-Budde Cc: Andreas Koensgen Cc: Paul Mackerras Cc: Rodolfo Giometti Cc: Peter Ujfalusi Cc: Liam Girdwood Cc: Mark Brown Cc: Jaroslav Kysela Cc: Takashi Iwai Link: https://lore.kernel.org/r/20210505091928.22010-15-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman