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@xxxxxxxxxxxxxx> > --- > 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. > > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
