[alsa-devel] [PATCH] ASoC: Fix UBSAN warning at snd_soc_get/put_volsw_sx()
In functions snd_soc_get_volsw_sx() or snd_soc_put_volsw_sx(), if the result of (min + max) is negative, then fls() returns signed integer with value as 32. This leads to signed integer overflow as complete operation is considered as signed integer.
UBSAN: Undefined behaviour in sound/soc/soc-ops.c:382:50 signed integer overflow: -2147483648 - 1 cannot be represented in type 'int' Call trace: [<ffffff852f746fe4>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffff852f746fe4>] dump_stack+0xec/0x158 lib/dump_stack.c:51 [<ffffff852f7b5f3c>] ubsan_epilogue+0x18/0x50 lib/ubsan.c:164 [<ffffff852f7b6840>] handle_overflow+0xf8/0x130 lib/ubsan.c:195 [<ffffff852f7b68f0>] __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:211 [<ffffff85307971a0>] snd_soc_get_volsw_sx+0x1a8/0x1f8 sound/soc/soc-ops.c:382
Typecast the operation to unsigned int to fix the issue.
Signed-off-by: Rohit kumar rohitkr@codeaurora.org --- sound/soc/soc-ops.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c index 592efb3..f8e3190 100644 --- a/sound/soc/soc-ops.c +++ b/sound/soc/soc-ops.c @@ -373,7 +373,7 @@ int snd_soc_get_volsw_sx(struct snd_kcontrol *kcontrol, unsigned int rshift = mc->rshift; int max = mc->max; int min = mc->min; - unsigned int mask = (1 << (fls(min + max) - 1)) - 1; + unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1); unsigned int val; int ret;
@@ -418,7 +418,7 @@ int snd_soc_put_volsw_sx(struct snd_kcontrol *kcontrol, unsigned int rshift = mc->rshift; int max = mc->max; int min = mc->min; - unsigned int mask = (1 << (fls(min + max) - 1)) - 1; + unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1); int err = 0; unsigned int val, val_mask, val2 = 0;
On Mon, 10 Sep 2018 19:33:56 +0200, Rohit kumar wrote:
In functions snd_soc_get_volsw_sx() or snd_soc_put_volsw_sx(), if the result of (min + max) is negative, then fls() returns signed integer with value as 32. This leads to signed integer overflow as complete operation is considered as signed integer.
UBSAN: Undefined behaviour in sound/soc/soc-ops.c:382:50 signed integer overflow: -2147483648 - 1 cannot be represented in type 'int' Call trace: [<ffffff852f746fe4>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffff852f746fe4>] dump_stack+0xec/0x158 lib/dump_stack.c:51 [<ffffff852f7b5f3c>] ubsan_epilogue+0x18/0x50 lib/ubsan.c:164 [<ffffff852f7b6840>] handle_overflow+0xf8/0x130 lib/ubsan.c:195 [<ffffff852f7b68f0>] __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:211 [<ffffff85307971a0>] snd_soc_get_volsw_sx+0x1a8/0x1f8 sound/soc/soc-ops.c:382
Typecast the operation to unsigned int to fix the issue.
Signed-off-by: Rohit kumar rohitkr@codeaurora.org
sound/soc/soc-ops.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c index 592efb3..f8e3190 100644 --- a/sound/soc/soc-ops.c +++ b/sound/soc/soc-ops.c @@ -373,7 +373,7 @@ int snd_soc_get_volsw_sx(struct snd_kcontrol *kcontrol, unsigned int rshift = mc->rshift; int max = mc->max; int min = mc->min;
- unsigned int mask = (1 << (fls(min + max) - 1)) - 1;
- unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1);
Cat it be simpler like below instead? unsigned int mask = (1U << (fls(min + max) - 1)) - 1;
thanks,
Takashi
unsigned int val; int ret;
@@ -418,7 +418,7 @@ int snd_soc_put_volsw_sx(struct snd_kcontrol *kcontrol, unsigned int rshift = mc->rshift; int max = mc->max; int min = mc->min;
- unsigned int mask = (1 << (fls(min + max) - 1)) - 1;
- unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1); int err = 0; unsigned int val, val_mask, val2 = 0;
-- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.
Thanks Takashi for reviewing.
On 9/10/2018 11:56 PM, Takashi Iwai wrote:
On Mon, 10 Sep 2018 19:33:56 +0200, Rohit kumar wrote:
In functions snd_soc_get_volsw_sx() or snd_soc_put_volsw_sx(), if the result of (min + max) is negative, then fls() returns signed integer with value as 32. This leads to signed integer overflow as complete operation is considered as signed integer.
UBSAN: Undefined behaviour in sound/soc/soc-ops.c:382:50 signed integer overflow: -2147483648 - 1 cannot be represented in type 'int' Call trace: [<ffffff852f746fe4>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffff852f746fe4>] dump_stack+0xec/0x158 lib/dump_stack.c:51 [<ffffff852f7b5f3c>] ubsan_epilogue+0x18/0x50 lib/ubsan.c:164 [<ffffff852f7b6840>] handle_overflow+0xf8/0x130 lib/ubsan.c:195 [<ffffff852f7b68f0>] __ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:211 [<ffffff85307971a0>] snd_soc_get_volsw_sx+0x1a8/0x1f8 sound/soc/soc-ops.c:382
Typecast the operation to unsigned int to fix the issue.
Signed-off-by: Rohit kumar rohitkr@codeaurora.org
sound/soc/soc-ops.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c index 592efb3..f8e3190 100644 --- a/sound/soc/soc-ops.c +++ b/sound/soc/soc-ops.c @@ -373,7 +373,7 @@ int snd_soc_get_volsw_sx(struct snd_kcontrol *kcontrol, unsigned int rshift = mc->rshift; int max = mc->max; int min = mc->min;
- unsigned int mask = (1 << (fls(min + max) - 1)) - 1;
- unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1);
Cat it be simpler like below instead? unsigned int mask = (1U << (fls(min + max) - 1)) - 1;
Yes, let me just update it.
thanks,
Takashi
unsigned int val; int ret;
@@ -418,7 +418,7 @@ int snd_soc_put_volsw_sx(struct snd_kcontrol *kcontrol, unsigned int rshift = mc->rshift; int max = mc->max; int min = mc->min;
- unsigned int mask = (1 << (fls(min + max) - 1)) - 1;
- unsigned int mask = ((unsigned int)(1 << (fls(min + max) - 1)) - 1); int err = 0; unsigned int val, val_mask, val2 = 0;
-- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
Thanks, Rohit
participants (2)
-
Rohit kumar -
Takashi Iwai