diff mbox series

[V2,05/14] x86/fpu: Limit xstate copy size in xstateregs_set()

Message ID 20210606001323.429482447@linutronix.de
State New
Headers show
Series None | expand

Commit Message

Thomas Gleixner June 5, 2021, 11:47 p.m. UTC 
If the count argument is larger than the xstate size, this will happily
copy beyond the end of xstate.

Fixes: 91c3dba7dbc1 ("x86/fpu/xstate: Fix PTRACE frames for XSAVES")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
---
 arch/x86/kernel/fpu/regset.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

--- a/arch/x86/kernel/fpu/regset.c
+++ b/arch/x86/kernel/fpu/regset.c
@@ -117,7 +117,7 @@  int xstateregs_set(struct task_struct *t
 	/*
 	 * A whole standard-format XSAVE buffer is needed:
 	 */
-	if ((pos != 0) || (count < fpu_user_xstate_size))
+	if (pos != 0 || count != fpu_user_xstate_size)
 		return -EFAULT;
 
 	xsave = &fpu->state.xsave;