Re: [PATCH 14/15] kernel: convert futex_pi_state.refcount from atomic_t to refcount_t
On Fri, Jul 07, 2017 at 12:04:28PM +0300, Elena Reshetova wrote:
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova(a)intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel(a)gmail.com>
Signed-off-by: Kees Cook <keescook(a)chromium.org>
Signed-off-by: David Windsor <dwindsor(a)gmail.com>
I'll let tglx comment on the SoB chain, I know he likes those :-) You
did Cc him right, seeing how he's the maintainer of this stuff..
*sigh* you didn't :-( After so many patches send you _really_ should
know to Cc the right people.
---
kernel/futex.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
@@ -814,7 +815,7 @@ static struct futex_pi_state
*alloc_pi_state(void)
static void get_pi_state(struct futex_pi_state *pi_state)
{
- WARN_ON_ONCE(!atomic_inc_not_zero(&pi_state->refcount));
+ WARN_ON_ONCE(!refcount_inc_not_zero(&pi_state->refcount));
}
I think we have refcount_inc() for just that case, no?