kernel.git/sound/core/seq/oss, branch linux-5.0.y

ALSA: seq: oss: Fix Spectre v1 vulnerability

2019-04-03T04:27:29Z

commit c709f14f0616482b67f9fbcb965e1493a03ff30b upstream. dev is indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: sound/core/seq/oss/seq_oss_synth.c:626 snd_seq_oss_synth_make_info() warn: potential spectre issue 'dp->synths' [w] (local cap) Fix this by sanitizing dev before using it to index dp->synths. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://lore.kernel.org/lkml/20180423164740.GY17484@dhcp22.suse.cz/ Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: seq: oss: Use the standard fall-through annotation

2018-10-12T07:31:29Z

As a preparatory patch for the upcoming -Wimplicit-fallthrough compiler checks, replace with the standard "fall through" annotation. Unfortunately gcc doesn't understand a chattier text. Signed-off-by: Takashi Iwai

ALSA: seq_oss: Mark expected switch fall-through

2018-08-04T06:30:45Z

In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Warning level 2 was used: -Wimplicit-fallthrough=2 Signed-off-by: Gustavo A. R. Silva Signed-off-by: Takashi Iwai

ALSA: seq: Minor cleanup of MIDI event parser helpers

2018-08-01T20:54:35Z

snd_midi_event_encode_byte() can never fail, and it can return rather true/false. Change the return type to bool, adjust the argument to receive a MIDI byte as unsigned char, and adjust the comment accordingly. This allows callers to drop error checks, which simplifies the code. Meanwhile, snd_midi_event_encode() helper is used only in seq_midi.c, and it can be better folded into it. This will reduce the total amount of lines in the end. Signed-off-by: Takashi Iwai

ALSA: seq: Fix poll() error return

2018-07-26T06:23:26Z

The sanity checks in ALSA sequencer and OSS sequencer emulation codes return falsely -ENXIO from poll callback. They should be EPOLLERR instead. This was caught thanks to the recent change to the return value. Cc: Signed-off-by: Takashi Iwai

ALSA: seq: oss: Hardening for potential Spectre v1

2018-04-25T08:37:45Z

As Smatch recently suggested, a few places in OSS sequencer codes may expand the array directly from the user-space value with speculation, namely there are a significant amount of references to either info->ch[] or dp->synths[] array: sound/core/seq/oss/seq_oss_event.c:315 note_on_event() warn: potential spectre issue 'info->ch' (local cap) sound/core/seq/oss/seq_oss_event.c:362 note_off_event() warn: potential spectre issue 'info->ch' (local cap) sound/core/seq/oss/seq_oss_synth.c:470 snd_seq_oss_synth_load_patch() warn: potential spectre issue 'dp->synths' (local cap) sound/core/seq/oss/seq_oss_event.c:293 note_on_event() warn: potential spectre issue 'dp->synths' sound/core/seq/oss/seq_oss_event.c:353 note_off_event() warn: potential spectre issue 'dp->synths' sound/core/seq/oss/seq_oss_synth.c:506 snd_seq_oss_synth_sysex() warn: potential spectre issue 'dp->synths' sound/core/seq/oss/seq_oss_synth.c:580 snd_seq_oss_synth_ioctl() warn: potential spectre issue 'dp->synths' Although all these seem doing only the first load without further reference, we may want to stay in a safer side, so hardening with array_index_nospec() would still make sense. We may put array_index_nospec() at each place, but here we take a different approach: - For dp->synths[], change the helpers to retrieve seq_oss_synthinfo pointer directly instead of the array expansion at each place - For info->ch[], harden in a normal way, as there are only a couple of places As a result, the existing helper, snd_seq_oss_synth_is_valid() is replaced with snd_seq_oss_synth_info(). Also, we cover MIDI device where a similar array expansion is done, too, although it wasn't reported by Smatch. BugLink: https://marc.info/?l=linux-kernel&m=152411496503418&w=2 Reported-by: Dan Carpenter Cc: Signed-off-by: Takashi Iwai

ALSA: seq: oss: Fix unbalanced use lock for synth MIDI device

2018-04-25T08:37:45Z

When get_synthdev() is called for a MIDI device, it returns the fixed midi_synth_dev without the use refcounting. OTOH, the caller is supposed to unreference unconditionally after the usage, so this would lead to unbalanced refcount. This patch corrects the behavior and keep up the refcount balance also for the MIDI synth device. Cc: Signed-off-by: Takashi Iwai

vfs: do bulk POLL* -> EPOLL* replacement

2018-02-11T22:34:03Z

This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^$[^\"]*$$\$/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro Signed-off-by: Linus Torvalds

sound: annotate ->poll() instances

2017-11-27T21:20:02Z

Signed-off-by: Al Viro

ALSA: seq: Fix OSS sysex delivery in OSS emulation

2017-11-07T15:05:24Z

The SYSEX event delivery in OSS sequencer emulation assumed that the event is encoded in the variable-length data with the straight buffering. This was the normal behavior in the past, but during the development, the chained buffers were introduced for carrying more data, while the OSS code was left intact. As a result, when a SYSEX event with the chained buffer data is passed to OSS sequencer port, it may end up with the wrong memory access, as if it were having a too large buffer. This patch addresses the bug, by applying the buffer data expansion by the generic snd_seq_dump_var_event() helper function. Reported-by: syzbot Reported-by: Mark Salyzyn Cc: Signed-off-by: Takashi Iwai