diff mbox series

[v14,1/9] nptl: initialize cpu_id_start prior to rseq registration

Message ID 20241121190924.837446-2-mjeanson@efficios.com (mailing list archive)
State Committed
Commit d9f40387d3305d97e30a8cf8724218c42a63680a
Delegated to: Florian Weimer
Headers
Series Add rseq extensible ABI support |

Checks

Context Check Description
redhat-pt-bot/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Michael Jeanson Nov. 21, 2024, 7:08 p.m. UTC 
  When adding explicit initialization of rseq fields prior to
registration, I glossed over the fact that 'cpu_id_start' is also
documented as initialized by user-space.

While current kernels don't validate the content of this field on
registration, future ones could.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
---
 sysdeps/unix/sysv/linux/rseq-internal.h | 1 +
 1 file changed, 1 insertion(+)

Comments

Mathieu Desnoyers Nov. 21, 2024, 7:11 p.m. UTC | #1 
On 2024-11-21 14:08, Michael Jeanson wrote:
> When adding explicit initialization of rseq fields prior to
> registration, I glossed over the fact that 'cpu_id_start' is also
> documented as initialized by user-space.
> 
> While current kernels don't validate the content of this field on
> registration, future ones could.
> 
> Signed-off-by: Michael Jeanson <mjeanson@efficios.com>

Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

> ---
>   sysdeps/unix/sysv/linux/rseq-internal.h | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
> index 37a8f630b6..ef3eab1fef 100644
> --- a/sysdeps/unix/sysv/linux/rseq-internal.h
> +++ b/sysdeps/unix/sysv/linux/rseq-internal.h
> @@ -56,6 +56,7 @@ rseq_register_current_thread (struct pthread *self, bool do_rseq)
>            registration, there is no guarantee that struct pthread is
>            cleared on all architectures.  */
>         THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_UNINITIALIZED);
> +      THREAD_SETMEM (self, rseq_area.cpu_id_start, 0);
>         THREAD_SETMEM (self, rseq_area.rseq_cs, 0);
>         THREAD_SETMEM (self, rseq_area.flags, 0);
>
diff mbox series

Patch

diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
index 37a8f630b6..ef3eab1fef 100644
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -56,6 +56,7 @@  rseq_register_current_thread (struct pthread *self, bool do_rseq)
          registration, there is no guarantee that struct pthread is
          cleared on all architectures.  */
       THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_UNINITIALIZED);
+      THREAD_SETMEM (self, rseq_area.cpu_id_start, 0);
       THREAD_SETMEM (self, rseq_area.rseq_cs, 0);
       THREAD_SETMEM (self, rseq_area.flags, 0);