[alsa-devel] [PATCH] ALSA: au88x0: avoid theoretical uninitialized access
The latest gcc-7.0.1 snapshot points out that we if nr_ch is zero, we never initialize some variables:
sound/pci/au88x0/au88x0_core.c: In function 'vortex_adb_allocroute': sound/pci/au88x0/au88x0_core.c:2304:68: error: 'mix[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized] sound/pci/au88x0/au88x0_core.c:2305:58: error: 'src[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized]
I assume this can never happen in practice, but adding a check here doesn't hurt either and avoids the warning. The code has been unchanged since the start of git history.
Signed-off-by: Arnd Bergmann arnd@arndb.de --- sound/pci/au88x0/au88x0_core.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/sound/pci/au88x0/au88x0_core.c b/sound/pci/au88x0/au88x0_core.c index e1af24f87566..c308a4f70550 100644 --- a/sound/pci/au88x0/au88x0_core.c +++ b/sound/pci/au88x0/au88x0_core.c @@ -2279,6 +2279,9 @@ vortex_adb_allocroute(vortex_t *vortex, int dma, int nr_ch, int dir, } else { int src[2], mix[2];
+ if (nr_ch < 1) + return -EINVAL; + /* Get SRC and MIXER hardware resources. */ for (i = 0; i < nr_ch; i++) { if ((mix[i] =
On Thu, 23 Mar 2017 16:15:55 +0100, Arnd Bergmann wrote:
The latest gcc-7.0.1 snapshot points out that we if nr_ch is zero, we never initialize some variables:
sound/pci/au88x0/au88x0_core.c: In function 'vortex_adb_allocroute': sound/pci/au88x0/au88x0_core.c:2304:68: error: 'mix[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized] sound/pci/au88x0/au88x0_core.c:2305:58: error: 'src[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized]
I assume this can never happen in practice, but adding a check here doesn't hurt either and avoids the warning. The code has been unchanged since the start of git history.
Signed-off-by: Arnd Bergmann arnd@arndb.de
Yeah, this shouldn't happen in practice, but better to cover. I applied the patch now. Thanks.
Takashi
sound/pci/au88x0/au88x0_core.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/sound/pci/au88x0/au88x0_core.c b/sound/pci/au88x0/au88x0_core.c index e1af24f87566..c308a4f70550 100644 --- a/sound/pci/au88x0/au88x0_core.c +++ b/sound/pci/au88x0/au88x0_core.c @@ -2279,6 +2279,9 @@ vortex_adb_allocroute(vortex_t *vortex, int dma, int nr_ch, int dir, } else { int src[2], mix[2];
if (nr_ch < 1)return -EINVAL;- /* Get SRC and MIXER hardware resources. */ for (i = 0; i < nr_ch; i++) { if ((mix[i] =
-- 2.9.0
participants (2)
-
Arnd Bergmann -
Takashi Iwai