]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
ALSA: fireface: Fix integer overflow in transmit_midi_msg()
authorGeert Uytterhoeven <geert+renesas@glider.be>
Mon, 11 Jan 2021 13:02:50 +0000 (14:02 +0100)
committerTakashi Iwai <tiwai@suse.de>
Tue, 12 Jan 2021 13:57:29 +0000 (14:57 +0100)
commite7c22eeaff8565d9a8374f320238c251ca31480b
treee6e4fa08c235fd927ac0faa8de70e35889a35ca8
parent615d435400435876ac68c1de37e9526a9164eaec
ALSA: fireface: Fix integer overflow in transmit_midi_msg()

As snd_ff.rx_bytes[] is unsigned int, and NSEC_PER_SEC is 1000000000L,
the second multiplication in

    ff->rx_bytes[port] * 8 * NSEC_PER_SEC / 31250

always overflows on 32-bit platforms, truncating the result.  Fix this
by precalculating "NSEC_PER_SEC / 31250", which is an integer constant.

Note that this assumes ff->rx_bytes[port] <= 16777.

Fixes: 19174295788de77d ("ALSA: fireface: add transaction support")
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20210111130251.361335-2-geert+renesas@glider.be
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/firewire/fireface/ff-transaction.c