83f0ba8592
commit 4a63bd179fa8d3fcc44a0d9d71d941ddd62f0c4e upstream. Currently ALSA timer doesn't have the lower limit of the start tick time, and it allows a very small size, e.g. 1 tick with 1ns resolution for hrtimer. Such a situation may lead to an unexpected RCU stall, where the callback repeatedly queuing the expire update, as reported by fuzzer. This patch introduces a sanity check of the timer start tick time, so that the system returns an error when a too small start size is set. As of this patch, the lower limit is hard-coded to 100us, which is small enough but can still work somehow. Reported-by: syzbot+43120c2af6ca2938cc38@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/000000000000fa00a1061740ab6d@google.com Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20240514182745.4015-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de> [ backport note: the error handling is changed, as the original commit is based on the recent cleanup with guard() in commit beb45974dd49 -- tiwai ] Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| oss | ||
| seq | ||
| Kconfig | ||
| Makefile | ||
| compress_offload.c | ||
| control.c | ||
| control_compat.c | ||
| control_led.c | ||
| ctljack.c | ||
| device.c | ||
| hrtimer.c | ||
| hwdep.c | ||
| hwdep_compat.c | ||
| info.c | ||
| info_oss.c | ||
| init.c | ||
| isadma.c | ||
| jack.c | ||
| memalloc.c | ||
| memalloc_local.h | ||
| memory.c | ||
| misc.c | ||
| pcm.c | ||
| pcm_compat.c | ||
| pcm_dmaengine.c | ||
| pcm_drm_eld.c | ||
| pcm_iec958.c | ||
| pcm_lib.c | ||
| pcm_local.h | ||
| pcm_memory.c | ||
| pcm_misc.c | ||
| pcm_native.c | ||
| pcm_param_trace.h | ||
| pcm_timer.c | ||
| pcm_trace.h | ||
| rawmidi.c | ||
| rawmidi_compat.c | ||
| seq_device.c | ||
| sgbuf.c | ||
| sound.c | ||
| sound_oss.c | ||
| timer.c | ||
| timer_compat.c | ||
| vmaster.c | ||