From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Subject: [patch] ALSA: bits vs bytes bug in snd_card_create() Date: Thu, 23 Jan 2014 11:21:28 +0300 Message-ID: <20140123082128.GA28688@elgon.mountain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: kernel-janitors-owner@vger.kernel.org To: Jaroslav Kysela Cc: Takashi Iwai , Yacine Belkadi , alsa-devel@alsa-project.org, kernel-janitors@vger.kernel.org List-Id: alsa-devel@alsa-project.org 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. Fixes: 7bb2491b35a2 ('ALSA: Add kconfig to specify the max card numbers') Signed-off-by: Dan Carpenter --- WARNING: Please check this one carefully because I might be wrong. diff --git a/sound/core/init.c b/sound/core/init.c index 1351f22f651c..e9e3db321e64 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -183,7 +183,7 @@ int snd_card_create(int idx, const char *xid, 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]) { From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Thu, 23 Jan 2014 08:21:28 +0000 Subject: [patch] ALSA: bits vs bytes bug in snd_card_create() Message-Id: <20140123082128.GA28688@elgon.mountain> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jaroslav Kysela Cc: Takashi Iwai , Yacine Belkadi , alsa-devel@alsa-project.org, kernel-janitors@vger.kernel.org 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. Fixes: 7bb2491b35a2 ('ALSA: Add kconfig to specify the max card numbers') Signed-off-by: Dan Carpenter --- WARNING: Please check this one carefully because I might be wrong. diff --git a/sound/core/init.c b/sound/core/init.c index 1351f22f651c..e9e3db321e64 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -183,7 +183,7 @@ int snd_card_create(int idx, const char *xid, 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]) {