This is a note to let you know that I've just added the patch titled ALSA: info: Return error for invalid read/write to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: alsa-info-return-error-for-invalid-read-write.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 6809cd682b82dfff47943850d1a8c714f971b5ca Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@xxxxxxx> Date: Sun, 30 Oct 2016 22:13:19 +0100 Subject: ALSA: info: Return error for invalid read/write From: Takashi Iwai <tiwai@xxxxxxx> commit 6809cd682b82dfff47943850d1a8c714f971b5ca upstream. Currently the ALSA proc handler allows read or write even if the proc file were write-only or read-only. It's mostly harmless, does thing but allocating memory and ignores the input/output. But it doesn't tell user about the invalid use, and it's confusing and inconsistent in comparison with other proc files. This patch adds some sanity checks and let the proc handler returning an -EIO error when the invalid read/write is performed. Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/core/info.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/sound/core/info.c +++ b/sound/core/info.c @@ -325,6 +325,8 @@ static ssize_t snd_info_text_entry_write size_t next; int err = 0; + if (!entry->c.text.write) + return -EIO; pos = *offset; if (!valid_pos(pos, count)) return -EIO; @@ -366,7 +368,9 @@ static int snd_info_seq_show(struct seq_ struct snd_info_private_data *data = seq->private; struct snd_info_entry *entry = data->entry; - if (entry->c.text.read) { + if (!entry->c.text.read) { + return -EIO; + } else { data->rbuffer->buffer = (char *)seq; /* XXX hack! */ entry->c.text.read(entry, data->rbuffer); } Patches currently in stable-queue which might be from tiwai@xxxxxxx are queue-4.4/alsa-info-limit-the-proc-text-input-size.patch queue-4.4/alsa-info-return-error-for-invalid-read-write.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html