From: Josh Poimboeuf The kernel doesn't have direct visibility to the ELF contents of shared libraries. Add some prctl() interfaces which allow glibc to tell the kernel where to find .sframe sections. [ This adds an interface for prctl() for testing loading of sframes for libraries. But this interface should really be a system call. This patch is for testing purposes only and should not be applied to mainline. ] Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) Reviewed-by: Indu Bhagat Signed-off-by: Jens Remus --- Notes (jremus): Changes in v14: - Bump PR_ADD_SFRAME and PR_REMOVE_SFRAME. include/uapi/linux/prctl.h | 6 +++++- kernel/sys.c | 8 ++++++++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index b6ec6f693719..0aa0ec971843 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -368,7 +368,7 @@ struct prctl_mm_map { * configuration. All bits may be locked via this call, including * undefined bits. */ -#define PR_LOCK_SHADOW_STACK_STATUS 76 +#define PR_LOCK_SHADOW_STACK_STATUS 76 /* * Controls the mode of timer_create() for CRIU restore operations. @@ -416,4 +416,8 @@ struct prctl_mm_map { # define PR_CFI_DISABLE _BITUL(1) # define PR_CFI_LOCK _BITUL(2) +/* SFRAME management */ +#define PR_ADD_SFRAME 82 +#define PR_REMOVE_SFRAME 83 + #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 62e842055cc9..6e81e82bc991 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -65,6 +65,7 @@ #include #include #include +#include #include @@ -2906,6 +2907,13 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, break; if (arg3 & PR_CFI_LOCK && !(arg3 & PR_CFI_DISABLE)) error = arch_prctl_lock_branch_landing_pad_state(me); + case PR_ADD_SFRAME: + error = sframe_add_section(arg2, arg3, arg4, arg5); + break; + case PR_REMOVE_SFRAME: + if (arg3 || arg4 || arg5) + return -EINVAL; + error = sframe_remove_section(arg2); break; default: trace_task_prctl_unknown(option, arg2, arg3, arg4, arg5); -- 2.51.0