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ALSA: bits vs bytes bug in snd_card_create()
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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: 7bb2491 ('ALSA: Add kconfig to specify the max card numbers')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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Dan Carpenter authored and Takashi Iwai committed Jan 23, 2014
1 parent 2387083 commit 4c3773e
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions sound/core/init.c
Original file line number Diff line number Diff line change
Expand Up @@ -170,7 +170,7 @@ 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 (module_slot_match(module, idx2)) {
Expand All @@ -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]) {
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