[alsa-devel] [PATCH] ALSA: xen-front: fix unintention integer overflow on left shifts
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From: Colin Ian King colin.king@canonical.com
Shifting the integer value 1 is evaluated using 32-bit arithmetic and then used in an expression that expects a 64-bit value, so there is potentially an integer overflow. Fix this by using the BIT_ULL macro to perform the shift.
Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Colin Ian King colin.king@canonical.com --- sound/xen/xen_snd_front_alsa.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c index b14ab512c2ce..e01631959ed8 100644 --- a/sound/xen/xen_snd_front_alsa.c +++ b/sound/xen/xen_snd_front_alsa.c @@ -196,7 +196,7 @@ static u64 to_sndif_formats_mask(u64 alsa_formats) mask = 0; for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++) if (pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa) & alsa_formats) - mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif; + mask |= BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif);
return mask; } @@ -208,7 +208,7 @@ static u64 to_alsa_formats_mask(u64 sndif_formats)
mask = 0; for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++) - if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats) + if (BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif) & sndif_formats) mask |= pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa);
return mask;
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On Thu, 27 Jun 2019 18:58:53 +0200, Colin King wrote:
From: Colin Ian King colin.king@canonical.com
Shifting the integer value 1 is evaluated using 32-bit arithmetic and then used in an expression that expects a 64-bit value, so there is potentially an integer overflow. Fix this by using the BIT_ULL macro to perform the shift.
Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Colin Ian King colin.king@canonical.com
The fix is correct, but luckily we didn't hit the integer overflow, as all passed values are less than 32bit.
In anyway, applied now. Thanks.
Takashi
sound/xen/xen_snd_front_alsa.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c index b14ab512c2ce..e01631959ed8 100644 --- a/sound/xen/xen_snd_front_alsa.c +++ b/sound/xen/xen_snd_front_alsa.c @@ -196,7 +196,7 @@ static u64 to_sndif_formats_mask(u64 alsa_formats) mask = 0; for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++) if (pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa) & alsa_formats)
mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
mask |= BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif);
return mask;
} @@ -208,7 +208,7 @@ static u64 to_alsa_formats_mask(u64 sndif_formats)
mask = 0; for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
if (BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif) & sndif_formats) mask |= pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa);
return mask;
-- 2.20.1
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On 6/28/19 11:46 AM, Takashi Iwai wrote:
On Thu, 27 Jun 2019 18:58:53 +0200, Colin King wrote:
From: Colin Ian King colin.king@canonical.com
Shifting the integer value 1 is evaluated using 32-bit arithmetic and then used in an expression that expects a 64-bit value, so there is potentially an integer overflow. Fix this by using the BIT_ULL macro to perform the shift.
Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Colin Ian King colin.king@canonical.com
Thank you for you patch, Oleksandr
The fix is correct, but luckily we didn't hit the integer overflow, as all passed values are less than 32bit.
In anyway, applied now. Thanks.
Takashi
sound/xen/xen_snd_front_alsa.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c index b14ab512c2ce..e01631959ed8 100644 --- a/sound/xen/xen_snd_front_alsa.c +++ b/sound/xen/xen_snd_front_alsa.c @@ -196,7 +196,7 @@ static u64 to_sndif_formats_mask(u64 alsa_formats) mask = 0; for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++) if (pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa) & alsa_formats)
mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
mask |= BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif);
return mask; }
@@ -208,7 +208,7 @@ static u64 to_alsa_formats_mask(u64 sndif_formats)
mask = 0; for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
if (BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif) & sndif_formats) mask |= pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa);
return mask;
-- 2.20.1
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participants (3)
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Colin King
-
Oleksandr Andrushchenko
-
Takashi Iwai