From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Takashi Iwai Subject: [PATCH 3.13 090/140] ALSA: bits vs bytes bug in snd_card_create() Date: Tue, 4 Feb 2014 13:11:17 -0800 Message-Id: <20140204211039.538015801@linuxfoundation.org> In-Reply-To: <20140204211036.967663852@linuxfoundation.org> References: <20140204211036.967663852@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 4c3773eda49c872a3034382f8ec3080002e715bf upstream. The test here is intended intended to prevent shift wrapping bugs when we do "1U << idx2". We should consider the number of bits in a u32 instead of the number of bytes. [fix another chunk similarly by tiwai] Fixes: 7bb2491b35a2 ('ALSA: Add kconfig to specify the max card numbers') Signed-off-by: Dan Carpenter Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/sound/core/init.c +++ b/sound/core/init.c @@ -170,7 +170,7 @@ int snd_card_create(int idx, const char if (idx < 0) { for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) { /* idx == -1 == 0xffff means: take any free slot */ - if (idx2 < sizeof(int) && !(idx & (1U << idx2))) + if (idx2 < 32 && !(idx & (1U << idx2))) continue; if (!test_bit(idx2, snd_cards_lock)) { if (module_slot_match(module, idx2)) { @@ -183,7 +183,7 @@ int snd_card_create(int idx, const char if (idx < 0) { for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) { /* idx == -1 == 0xffff means: take any free slot */ - if (idx2 < sizeof(int) && !(idx & (1U << idx2))) + if (idx2 < 32 && !(idx & (1U << idx2))) continue; if (!test_bit(idx2, snd_cards_lock)) { if (!slots[idx2] || !*slots[idx2]) {