Gaosheng Cui cf2ea3c86a ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt ... I got a null-ptr-defer error report when I do the following tests on the qemu platform: make defconfig and CONFIG_PARPORT=m, CONFIG_PARPORT_PC=m, CONFIG_SND_MTS64=m Then making test scripts: cat>test_mod1.sh<<EOF modprobe snd-mts64 modprobe snd-mts64 EOF Executing the script, perhaps several times, we will get a null-ptr-defer report, as follow: syzkaller:~# ./test_mod.sh snd_mts64: probe of snd_mts64.0 failed with error -5 modprobe: ERROR: could not insert 'snd_mts64': No such device BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP PTI CPU: 0 PID: 205 Comm: modprobe Not tainted 6.1.0-rc8-00588-g76dcd734eca2 #6 Call Trace: <IRQ> snd_mts64_interrupt+0x24/0xa0 [snd_mts64] parport_irq_handler+0x37/0x50 [parport] __handle_irq_event_percpu+0x39/0x190 handle_irq_event_percpu+0xa/0x30 handle_irq_event+0x2f/0x50 handle_edge_irq+0x99/0x1b0 __common_interrupt+0x5d/0x100 common_interrupt+0xa0/0xc0 </IRQ> <TASK> asm_common_interrupt+0x22/0x40 RIP: 0010:_raw_write_unlock_irqrestore+0x11/0x30 parport_claim+0xbd/0x230 [parport] snd_mts64_probe+0x14a/0x465 [snd_mts64] platform_probe+0x3f/0xa0 really_probe+0x129/0x2c0 __driver_probe_device+0x6d/0xc0 driver_probe_device+0x1a/0xa0 __device_attach_driver+0x7a/0xb0 bus_for_each_drv+0x62/0xb0 __device_attach+0xe4/0x180 bus_probe_device+0x82/0xa0 device_add+0x550/0x920 platform_device_add+0x106/0x220 snd_mts64_attach+0x2e/0x80 [snd_mts64] port_check+0x14/0x20 [parport] bus_for_each_dev+0x6e/0xc0 __parport_register_driver+0x7c/0xb0 [parport] snd_mts64_module_init+0x31/0x1000 [snd_mts64] do_one_initcall+0x3c/0x1f0 do_init_module+0x46/0x1c6 load_module+0x1d8d/0x1e10 __do_sys_finit_module+0xa2/0xf0 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK> Kernel panic - not syncing: Fatal exception in interrupt Rebooting in 1 seconds.. The mts wa not initialized during interrupt, we add check for mts to fix this bug. Fixes: 68ab801e32 ("[ALSA] Add snd-mts64 driver for ESI Miditerminal 4140") Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> Link: https://lore.kernel.org/r/20221206061004.1222966-1-cuigaosheng1@huawei.com Signed-off-by: Takashi Iwai <tiwai@suse.de>		2022-12-06 11:12:12 +01:00
..
mpu401	ALSA: mpu401: Allocate resources with device-managed APIs	2021-07-19 16:17:30 +02:00
opl3	ALSA: drivers: opl3: Fix incorrect use of vp->state	2021-12-13 10:36:17 +01:00
opl4	ALSA: opl4: More constification	2020-01-05 16:15:08 +01:00
pcsp	ALSA: pcsp: Make hrtimer forwarding more robust	2021-09-28 10:58:08 +02:00
vx	ALSA: vx: Drop superfluous GFP setup	2022-08-24 08:00:26 +02:00
aloop.c	ALSA: aloop: Replace runtime->status->state reference to runtime->state	2022-09-27 08:47:13 +02:00
dummy.c	ALSA: dummy: Add customizable volume min/max.	2022-09-12 09:52:10 +02:00
Kconfig	ALSA: Add generic serial MIDI driver using serial bus API	2022-05-12 11:54:13 +02:00
Makefile	ALSA: Add generic serial MIDI driver using serial bus API	2022-05-12 11:54:13 +02:00
mtpav.c	ALSA: mtpav: Don't call card private_free at probe error path	2022-04-12 17:58:43 +02:00
mts64.c	ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt	2022-12-06 11:12:12 +01:00
portman2x4.c	ALSA: serial: Fix assignment in if condition	2021-06-09 17:30:34 +02:00
serial-generic.c	ALSA: Add generic serial MIDI driver using serial bus API	2022-05-12 11:54:13 +02:00
serial-u16550.c	ALSA: serial-u16550: Allocate resources with device-managed APIs	2021-07-19 16:17:30 +02:00
virmidi.c	ALSA: virmidi: Remove duplicated code	2022-01-06 16:08:18 +01:00