| Message ID | 1424095816-4414-1-git-send-email-sudeep.holla@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Feb 16, 2015 at 02:10:16PM +0000, Sudeep Holla wrote: > On architectures that depend on DT for obtaining cache hierarcy, we need > to validate the device node for all the cache indices, failing to do so > might result in wrong information being exposed to the userspace. > > This is quite possible on initial/incomplete versions of the device > trees. In such cases, it's better to bail out if all the required device > nodes are not present. > > This patch adds checks for the validation of device node for all the > caches and doesn't initialise the cacheinfo if there's any error. > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Reported-by: Mark Rutland <mark.rutland@arm.com> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > --- > drivers/base/cacheinfo.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c > index 6e64563361f0..7015bf05c828 100644 > --- a/drivers/base/cacheinfo.c > +++ b/drivers/base/cacheinfo.c > @@ -62,15 +62,21 @@ static int cache_setup_of_node(unsigned int cpu) > return -ENOENT; > } > > - while (np && index < cache_leaves(cpu)) { > + while (index < cache_leaves(cpu)) { > this_leaf = this_cpu_ci->info_list + index; > if (this_leaf->level != 1) > np = of_find_next_cache_node(np); > else > np = of_node_get(np);/* cpu node itself */ > + if (!np) > + break; > this_leaf->of_node = np; > index++; > } > + > + if (index != cache_leaves(cpu)) /* not all OF nodes populated */ > + return -ENOENT; > + > return 0; > } > > @@ -189,8 +195,10 @@ static int detect_cache_attributes(unsigned int cpu) > * will be set up here only if they are not populated already > */ > ret = cache_shared_cpu_map_setup(cpu); > - if (ret) > + if (ret) { > + pr_err("failed to setup cache hierarcy from DT\n"); It would probably be better if this were something like: pr_warn("Unable to detect cache hierarcy from DT for CPU %d\n", cpu); Otherwise, this looks sane to me, and it would be nice to have this in ASAP so as to avoid exposing erroneous information to userspace. So: Acked-by: Mark Rutland <mark.rutland@arm.com> Thanks, Mark. > goto free_ci; > + } > return 0; > > free_ci: > -- > 1.9.1 > >
On 23/02/15 15:14, Mark Rutland wrote: > On Mon, Feb 16, 2015 at 02:10:16PM +0000, Sudeep Holla wrote: >> On architectures that depend on DT for obtaining cache hierarcy, we need >> to validate the device node for all the cache indices, failing to do so >> might result in wrong information being exposed to the userspace. >> >> This is quite possible on initial/incomplete versions of the device >> trees. In such cases, it's better to bail out if all the required device >> nodes are not present. >> >> This patch adds checks for the validation of device node for all the >> caches and doesn't initialise the cacheinfo if there's any error. >> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> >> Reported-by: Mark Rutland <mark.rutland@arm.com> >> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> >> --- >> drivers/base/cacheinfo.c | 12 ++++++++++-- >> 1 file changed, 10 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c >> index 6e64563361f0..7015bf05c828 100644 >> --- a/drivers/base/cacheinfo.c >> +++ b/drivers/base/cacheinfo.c [...] >> @@ -189,8 +195,10 @@ static int detect_cache_attributes(unsigned int cpu) >> * will be set up here only if they are not populated already >> */ >> ret = cache_shared_cpu_map_setup(cpu); >> - if (ret) >> + if (ret) { >> + pr_err("failed to setup cache hierarcy from DT\n"); > > It would probably be better if this were something like: > > pr_warn("Unable to detect cache hierarcy from DT for CPU %d\n", > cpu); > Agreed, will update and send v2. > Otherwise, this looks sane to me, and it would be nice to have this in > ASAP so as to avoid exposing erroneous information to userspace. So: > > Acked-by: Mark Rutland <mark.rutland@arm.com> > Thanks. Regards, Sudeep
diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 6e64563361f0..7015bf05c828 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -62,15 +62,21 @@ static int cache_setup_of_node(unsigned int cpu) return -ENOENT; } - while (np && index < cache_leaves(cpu)) { + while (index < cache_leaves(cpu)) { this_leaf = this_cpu_ci->info_list + index; if (this_leaf->level != 1) np = of_find_next_cache_node(np); else np = of_node_get(np);/* cpu node itself */ + if (!np) + break; this_leaf->of_node = np; index++; } + + if (index != cache_leaves(cpu)) /* not all OF nodes populated */ + return -ENOENT; + return 0; } @@ -189,8 +195,10 @@ static int detect_cache_attributes(unsigned int cpu) * will be set up here only if they are not populated already */ ret = cache_shared_cpu_map_setup(cpu); - if (ret) + if (ret) { + pr_err("failed to setup cache hierarcy from DT\n"); goto free_ci; + } return 0; free_ci:
On architectures that depend on DT for obtaining cache hierarcy, we need to validate the device node for all the cache indices, failing to do so might result in wrong information being exposed to the userspace. This is quite possible on initial/incomplete versions of the device trees. In such cases, it's better to bail out if all the required device nodes are not present. This patch adds checks for the validation of device node for all the caches and doesn't initialise the cacheinfo if there's any error. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> --- drivers/base/cacheinfo.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)