From: Jaroslav Kysela <perex@xxxxxxxx> commit d278a9de5e1837edbe57b2f1f95a104ff6c84846 upstream. The card identifier should contain only safe ASCII characters. The isalnum() returns true also for characters for non-ASCII characters. Link: https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/4135 Link: https://lore.kernel.org/linux-sound/yk3WTvKkwheOon_LzZlJ43PPInz6byYfBzpKkbasww1yzuiMRqn7n6Y8vZcXB-xwFCu_vb8hoNjv7DTNwH5TWjpEuiVsyn9HPCEXqwF4120=@protonmail.com/ Cc: stable@xxxxxxxxxxxxxxx Reported-by: Barnabás Pőcze <pobrn@xxxxxxxxxxxxxx> Signed-off-by: Jaroslav Kysela <perex@xxxxxxxx> Link: https://patch.msgid.link/20241002194649.1944696-1-perex@xxxxxxxx Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/core/init.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/sound/core/init.c +++ b/sound/core/init.c @@ -548,13 +548,19 @@ int snd_card_free(struct snd_card *card) } EXPORT_SYMBOL(snd_card_free); +/* check, if the character is in the valid ASCII range */ +static inline bool safe_ascii_char(char c) +{ + return isascii(c) && isalnum(c); +} + /* retrieve the last word of shortname or longname */ static const char *retrieve_id_from_card_name(const char *name) { const char *spos = name; while (*name) { - if (isspace(*name) && isalnum(name[1])) + if (isspace(*name) && safe_ascii_char(name[1])) spos = name + 1; name++; } @@ -581,12 +587,12 @@ static void copy_valid_id_string(struct { char *id = card->id; - while (*nid && !isalnum(*nid)) + while (*nid && !safe_ascii_char(*nid)) nid++; if (isdigit(*nid)) *id++ = isalpha(*src) ? *src : 'D'; while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) { - if (isalnum(*nid)) + if (safe_ascii_char(*nid)) *id++ = *nid; nid++; } @@ -684,7 +690,7 @@ card_id_store_attr(struct device *dev, s for (idx = 0; idx < copy; idx++) { c = buf[idx]; - if (!isalnum(c) && c != '_' && c != '-') + if (!safe_ascii_char(c) && c != '_' && c != '-') return -EINVAL; } memcpy(buf1, buf, copy); Patches currently in stable-queue which might be from perex@xxxxxxxx are queue-4.19/alsa-core-add-isascii-check-to-card-id-generator.patch