[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; }
Hi,
On Mar 19 2017 07:10, Clemens Ladisch wrote:
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
Reviewd-by: Takashi Sakamoto o-takashi@sakamocchi.jp
--- 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;
Regards
Takashi Sakamoto
On Sat, 18 Mar 2017 23:10:33 +0100, Clemens Ladisch wrote:
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
Applied (with Sakamoto-san's review tag) now. Thanks.
Takashi
--- 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;
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
participants (3)
-
Clemens Ladisch
-
Takashi Iwai
-
Takashi Sakamoto