tree 343beda600798c0c06e10e49e3f8402a42a72413
parent 027a9fe6835620422b6713892175716f3613dd9d
author Takashi Iwai <tiwai@suse.de> 1477861999 +0100
committer Takashi Iwai <tiwai@suse.de> 1478612246 +0100

ALSA: info: Return error for invalid read/write

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.

Cc: <stable@vger.kernel.org> # v4.2+
Signed-off-by: Takashi Iwai <tiwai@suse.de>