From: Josh Poimboeuf <[email protected]> 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. ] Cc: Masami Hiramatsu <[email protected]> Cc: Mathieu Desnoyers <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Andrii Nakryiko <[email protected]> Cc: Indu Bhagat <[email protected]> Cc: "Jose E. Marchesi" <[email protected]> Cc: Beau Belgrave <[email protected]> Cc: Jens Remus <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Florian Weimer <[email protected]> Cc: Sam James <[email protected]> Cc: Kees Cook <[email protected]> Cc: "Carlos O'Donell" <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]> Signed-off-by: Jens Remus <[email protected]> --- include/uapi/linux/prctl.h | 6 +++++- kernel/sys.c | 9 +++++++++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 51c4e8c82b1e..91d2c9eb3aa3 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. @@ -386,4 +386,8 @@ struct prctl_mm_map { # define PR_FUTEX_HASH_SET_SLOTS 1 # define PR_FUTEX_HASH_GET_SLOTS 2 +/* SFRAME management */ +#define PR_ADD_SFRAME 79 +#define PR_REMOVE_SFRAME 80 + #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 8b58eece4e58..ea088b643eb4 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -65,6 +65,7 @@ #include <linux/rcupdate.h> #include <linux/uidgid.h> #include <linux/cred.h> +#include <linux/sframe.h> #include <linux/nospec.h> @@ -2868,6 +2869,14 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, case PR_FUTEX_HASH: error = futex_hash_prctl(arg2, arg3, arg4); break; + 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); error = -EINVAL; -- 2.48.1
