From 167beb1756791e0806365a3f86a0da10d7a327ee Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Sat, 9 Nov 2019 19:16:58 +0100 Subject: ALSA: usb-audio: Fix missing error check at mixer resolution test A check of the return value from get_cur_mix_raw() is missing at the resolution test code in get_min_max_with_quirks(), which may leave the variable untouched, leading to a random uninitialized value, as detected by syzkaller fuzzer. Add the missing return error check for fixing that. Reported-and-tested-by: syzbot+abe1ab7afc62c6bb6377@syzkaller.appspotmail.com Cc: Link: https://lore.kernel.org/r/20191109181658.30368-1-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/usb/mixer.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 3fd1d1749edfc0..45eee5cc312e61 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -1229,7 +1229,8 @@ static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval, if (cval->min + cval->res < cval->max) { int last_valid_res = cval->res; int saved, test, check; - get_cur_mix_raw(cval, minchn, &saved); + if (get_cur_mix_raw(cval, minchn, &saved) < 0) + goto no_res_check; for (;;) { test = saved; if (test < cval->max) @@ -1249,6 +1250,7 @@ static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval, snd_usb_set_cur_mix_value(cval, minchn, 0, saved); } +no_res_check: cval->initialized = 1; } -- cgit 1.2.3-korg