Message ID | 1306425029-30649-2-git-send-email-apw@canonical.com |
---|---|
State | New |
Headers | show |
On Thu, 2011-05-26 at 16:50 +0100, Andy Whitcroft wrote: > From: Vasiliy Kulikov <segoon@openwall.com> > > pg_start is copied from userspace on AGPIOC_BIND and AGPIOC_UNBIND ioctl > cmds of agp_ioctl() and passed to agpioc_bind_wrap(). As said in the > comment, (pg_start + mem->page_count) may wrap in case of AGPIOC_BIND, > and it is not checked at all in case of AGPIOC_UNBIND. As a result, user > with sufficient privileges (usually "video" group) may generate either > local DoS or privilege escalation. > > Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> > Signed-off-by: Dave Airlie <airlied@redhat.com> > > CVE-1011-2022 > BugLink: http://bugs.launchpad.net/bugs/788684 > (cherry picked from commit 194b3da873fd334ef183806db751473512af29ce) > Signed-off-by: Andy Whitcroft <apw@canonical.com> Acked-by: Leann Ogasawara <leann.ogasawara@canonical.com> > --- > drivers/char/agp/generic.c | 11 ++++++++--- > 1 files changed, 8 insertions(+), 3 deletions(-) > > diff --git a/drivers/char/agp/generic.c b/drivers/char/agp/generic.c > index d2abf51..7858016 100644 > --- a/drivers/char/agp/generic.c > +++ b/drivers/char/agp/generic.c > @@ -1122,8 +1122,8 @@ int agp_generic_insert_memory(struct agp_memory * mem, off_t pg_start, int type) > return -EINVAL; > } > > - /* AK: could wrap */ > - if ((pg_start + mem->page_count) > num_entries) > + if (((pg_start + mem->page_count) > num_entries) || > + ((pg_start + mem->page_count) < pg_start)) > return -EINVAL; > > j = pg_start; > @@ -1157,7 +1157,7 @@ int agp_generic_remove_memory(struct agp_memory *mem, off_t pg_start, int type) > { > size_t i; > struct agp_bridge_data *bridge; > - int mask_type; > + int mask_type, num_entries; > > bridge = mem->bridge; > if (!bridge) > @@ -1169,6 +1169,11 @@ int agp_generic_remove_memory(struct agp_memory *mem, off_t pg_start, int type) > if (type != mem->type) > return -EINVAL; > > + num_entries = agp_num_entries(); > + if (((pg_start + mem->page_count) > num_entries) || > + ((pg_start + mem->page_count) < pg_start)) > + return -EINVAL; > + > mask_type = bridge->driver->agp_type_to_mask_type(bridge, type); > if (mask_type != 0) { > /* The generic routines know nothing of memory types */ > -- > 1.7.4.1 > >
diff --git a/drivers/char/agp/generic.c b/drivers/char/agp/generic.c index d2abf51..7858016 100644 --- a/drivers/char/agp/generic.c +++ b/drivers/char/agp/generic.c @@ -1122,8 +1122,8 @@ int agp_generic_insert_memory(struct agp_memory * mem, off_t pg_start, int type) return -EINVAL; } - /* AK: could wrap */ - if ((pg_start + mem->page_count) > num_entries) + if (((pg_start + mem->page_count) > num_entries) || + ((pg_start + mem->page_count) < pg_start)) return -EINVAL; j = pg_start; @@ -1157,7 +1157,7 @@ int agp_generic_remove_memory(struct agp_memory *mem, off_t pg_start, int type) { size_t i; struct agp_bridge_data *bridge; - int mask_type; + int mask_type, num_entries; bridge = mem->bridge; if (!bridge) @@ -1169,6 +1169,11 @@ int agp_generic_remove_memory(struct agp_memory *mem, off_t pg_start, int type) if (type != mem->type) return -EINVAL; + num_entries = agp_num_entries(); + if (((pg_start + mem->page_count) > num_entries) || + ((pg_start + mem->page_count) < pg_start)) + return -EINVAL; + mask_type = bridge->driver->agp_type_to_mask_type(bridge, type); if (mask_type != 0) { /* The generic routines know nothing of memory types */