signal: Expose SYS_USER_DISPATCH si_code type

SYS_USER_DISPATCH will be triggered when a syscall is sent to userspace
by the Syscall User Dispatch mechanism.  This adjusts eventual
BUILD_BUG_ON around the tree.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20201127193238.821364-3-krisman@collabora.com

diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c
index a7f3e12..d7b5187 100644 (file)
--- a/arch/x86/kernel/signal_compat.c
+++ b/arch/x86/kernel/signal_compat.c
@@ -31,7 +31,7 @@ static inline void signal_compat_build_tests(void)
        BUILD_BUG_ON(NSIGBUS  != 5);
        BUILD_BUG_ON(NSIGTRAP != 5);
        BUILD_BUG_ON(NSIGCHLD != 6);
-       BUILD_BUG_ON(NSIGSYS  != 1);
+       BUILD_BUG_ON(NSIGSYS  != 2);
 
        /* This is part of the ABI and can never change in size: */
        BUILD_BUG_ON(sizeof(compat_siginfo_t) != 128);

diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
index 7aacf93..d259700 100644 (file)
--- a/include/uapi/asm-generic/siginfo.h
+++ b/include/uapi/asm-generic/siginfo.h
@@ -286,7 +286,8 @@ typedef struct siginfo {
  * SIGSYS si_codes
  */
 #define SYS_SECCOMP    1       /* seccomp triggered */
-#define NSIGSYS                1
+#define SYS_USER_DISPATCH 2    /* syscall user dispatch triggered */
+#define NSIGSYS                2
 
 /*
  * SIGEMT si_codes