[alsa-devel] [PATCH] rawmidi: virtual: fix reading into a small buffer

In the special case for handling partial messages, the pointer calculations were wrong, which would result in data corruption.

Signed-off-by: Clemens Ladisch clemens@ladisch.de

--- alsa-lib/src/rawmidi/rawmidi_virt.c +++ alsa-lib/src/rawmidi/rawmidi_virt.c @@ -263,8 +263,8 @@ static ssize_t snd_rawmidi_virtual_read(snd_rawmidi_t *rmidi, void *buffer, size } size1 = virt->in_buf_size - virt->in_buf_ofs; if ((size_t)size1 > size) { - virt->in_buf_ofs += size1 - size; - memcpy(buffer, virt->in_buf_ptr, size); + memcpy(buffer, virt->in_buf_ptr + virt->in_buf_ofs, size); + virt->in_buf_ofs += size; result += size; break; }