[libvirt] [PATCH] Fix DMI uuid parsing.

valgrind was complaining that virUUIDParse was depending on an uninitialized value. Indeed it was; virSetHostUUIDStr() didn't initialize the dmiuuid buffer to 0's, meaning that anything after the string read from /sys was uninitialized. Clear out the dmiuuid buffer before use, and make sure to always leave a \0 at the end. Signed-off-by: Chris Lalancette <clalance@redhat.com> --- src/util/uuid.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/src/util/uuid.c b/src/util/uuid.c index f188148..9cafc2a 100644 --- a/src/util/uuid.c +++ b/src/util/uuid.c @@ -286,7 +286,8 @@ virSetHostUUIDStr(const char *uuid) return EEXIST; if (!uuid) { - if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid))) { + memset(dmiuuid, 0, sizeof(dmiuuid)); + if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid) - 1)) { if (!virUUIDParse(dmiuuid, host_uuid)) return 0; } -- 1.7.1.1

On Fri, Jul 30, 2010 at 10:22:20AM -0400, Chris Lalancette wrote:
valgrind was complaining that virUUIDParse was depending on an uninitialized value. Indeed it was; virSetHostUUIDStr() didn't initialize the dmiuuid buffer to 0's, meaning that anything after the string read from /sys was uninitialized. Clear out the dmiuuid buffer before use, and make sure to always leave a \0 at the end.
Signed-off-by: Chris Lalancette <clalance@redhat.com> --- src/util/uuid.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/src/util/uuid.c b/src/util/uuid.c index f188148..9cafc2a 100644 --- a/src/util/uuid.c +++ b/src/util/uuid.c @@ -286,7 +286,8 @@ virSetHostUUIDStr(const char *uuid) return EEXIST;
if (!uuid) { - if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid))) { + memset(dmiuuid, 0, sizeof(dmiuuid)); + if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid) - 1)) { if (!virUUIDParse(dmiuuid, host_uuid)) return 0; }
ACK, Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel@veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/

On 07/30/10 - 04:35:27PM, Daniel Veillard wrote:
On Fri, Jul 30, 2010 at 10:22:20AM -0400, Chris Lalancette wrote:
valgrind was complaining that virUUIDParse was depending on an uninitialized value. Indeed it was; virSetHostUUIDStr() didn't initialize the dmiuuid buffer to 0's, meaning that anything after the string read from /sys was uninitialized. Clear out the dmiuuid buffer before use, and make sure to always leave a \0 at the end.
Signed-off-by: Chris Lalancette <clalance@redhat.com> --- src/util/uuid.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/src/util/uuid.c b/src/util/uuid.c index f188148..9cafc2a 100644 --- a/src/util/uuid.c +++ b/src/util/uuid.c @@ -286,7 +286,8 @@ virSetHostUUIDStr(const char *uuid) return EEXIST;
if (!uuid) { - if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid))) { + memset(dmiuuid, 0, sizeof(dmiuuid)); + if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid) - 1)) { if (!virUUIDParse(dmiuuid, host_uuid)) return 0; }
ACK,
Thanks, pushed. -- Chris Lalancette
participants (2)
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Chris Lalancette
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Daniel Veillard