evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ALSA: info: Return error for invalid read/write

Browse source 
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@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Takashi Iwai 2016-10-30 22:13:19 +01:00 • committed by Greg Kroah-Hartman
parent 4dab3e4df9
commit c1ea2b3c07
1 changed files with 5 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
sound/core/info.c
View file

@ -325,6 +325,8 @@ static ssize_t snd_info_text_entry_write(struct file *file,
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_file *seq, void *p)
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);
}