arch/riscv/include/asm/stackprotector.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef _ASM_RISCV_STACKPROTECTOR_H
   4 #define _ASM_RISCV_STACKPROTECTOR_H
   5
   6 #include <linux/random.h>
   7 #include <linux/version.h>
   8
   9 extern unsigned long __stack_chk_guard;
  10
  11 /*
  12  * Initialize the stackprotector canary value.
  13  *
  14  * NOTE: this must only be called from functions that never return,
  15  * and it must always be inlined.
  16  */
  17 static __always_inline void boot_init_stack_canary(void)
  18 {
  19         unsigned long canary;
  20
  21         /* Try to get a semi random initial value. */
  22         get_random_bytes(&canary, sizeof(canary));
  23         canary ^= LINUX_VERSION_CODE;
  24         canary &= CANARY_MASK;
  25
  26         current->stack_canary = canary;
  27         if (!IS_ENABLED(CONFIG_STACKPROTECTOR_PER_TASK))
  28                 __stack_chk_guard = current->stack_canary;
  29 }
  30 #endif /* _ASM_RISCV_STACKPROTECTOR_H */