siginfo: add signal info for seccomp related SIGSYS

uClibc doesn't define signal info for the SIGSYS signal which is issued
in case of hitting a syscall prohibited by seccomp.
This is sad as it makes debugging seccomp filter policies impossible on
some architectures (at least ARM and PowerPC, maybe also others) which
do not coincidentally set si_value.sival_int as the syscall number.

To fix this, import the definitions and macros needed from glibc.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

5 files changed, 55 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/alpha/bits/siginfo.h b/libc/sysdeps/linux/alpha/bits/siginfo.h
index 0a37ad08b..7e476aa70 100644
--- a/libc/sysdeps/linux/alpha/bits/siginfo.h
+++ b/libc/sysdeps/linux/alpha/bits/siginfo.h
@@ -97,6 +97,14 @@ typedef struct siginfo
 	    int si_band;	/* Band event for SIGPOLL.  */
 	    int si_fd;
 	  } _sigpoll;
+
+	/* SIGSYS.  */
+	struct
+	  {
+	    void *_call_addr;   /* Calling user insn.  */
+	    int _syscall;       /* Triggering system call number.  */
+	    unsigned int _arch; /* AUDIT_ARCH_* of syscall.  */
+	  } _sigsys;
       } _sifields;
   } siginfo_t;
 
@@ -115,6 +123,9 @@ typedef struct siginfo
 # define si_addr	_sifields._sigfault.si_addr
 # define si_band	_sifields._sigpoll.si_band
 # define si_fd		_sifields._sigpoll.si_fd
+# define si_call_addr	_sifields._sigsys._call_addr
+# define si_syscall	_sifields._sigsys._syscall
+# define si_arch	_sifields._sigsys._arch
 
 
 /* Values for `si_code'.  Positive values are reserved for kernel-generated
diff --git a/libc/sysdeps/linux/common/bits/siginfo.h b/libc/sysdeps/linux/common/bits/siginfo.h
index c26e0668f..724f756cd 100644
--- a/libc/sysdeps/linux/common/bits/siginfo.h
+++ b/libc/sysdeps/linux/common/bits/siginfo.h
@@ -103,6 +103,14 @@ typedef struct siginfo
 	    long int si_band;	/* Band event for SIGPOLL.  */
 	    int si_fd;
 	  } _sigpoll;
+
+	/* SIGSYS.  */
+	struct
+	  {
+	    void *_call_addr;   /* Calling user insn.  */
+	    int _syscall;       /* Triggering system call number.  */
+	    unsigned int _arch; /* AUDIT_ARCH_* of syscall.  */
+	  } _sigsys;
       } _sifields;
   } siginfo_t;
 
@@ -121,6 +129,9 @@ typedef struct siginfo
 # define si_addr	_sifields._sigfault.si_addr
 # define si_band	_sifields._sigpoll.si_band
 # define si_fd		_sifields._sigpoll.si_fd
+# define si_call_addr	_sifields._sigsys._call_addr
+# define si_syscall	_sifields._sigsys._syscall
+# define si_arch	_sifields._sigsys._arch
 
 
 /* Values for `si_code'.  Positive values are reserved for kernel-generated
diff --git a/libc/sysdeps/linux/ia64/bits/siginfo.h b/libc/sysdeps/linux/ia64/bits/siginfo.h
index 3ac988baf..df18b3606 100644
--- a/libc/sysdeps/linux/ia64/bits/siginfo.h
+++ b/libc/sysdeps/linux/ia64/bits/siginfo.h
@@ -102,6 +102,14 @@ typedef struct siginfo
 	    long int si_band;	/* Band event for SIGPOLL.  */
 	    int si_fd;
 	  } _sigpoll;
+
+	/* SIGSYS.  */
+	struct
+	  {
+	    void *_call_addr;   /* Calling user insn.  */
+	    int _syscall;       /* Triggering system call number.  */
+	    unsigned int _arch; /* AUDIT_ARCH_* of syscall.  */
+	  } _sigsys;
       } _sifields;
   } siginfo_t;
 
@@ -120,6 +128,9 @@ typedef struct siginfo
 # define si_addr	_sifields._sigfault.si_addr
 # define si_band	_sifields._sigpoll.si_band
 # define si_fd		_sifields._sigpoll.si_fd
+# define si_call_addr	_sifields._sigsys._call_addr
+# define si_syscall	_sifields._sigsys._syscall
+# define si_arch	_sifields._sigsys._arch
 
 # ifdef __USE_GNU
 #  define si_imm	_sifields._sigfault._si_imm
diff --git a/libc/sysdeps/linux/mips/bits/siginfo.h b/libc/sysdeps/linux/mips/bits/siginfo.h
index 5199d4d99..b204301af 100644
--- a/libc/sysdeps/linux/mips/bits/siginfo.h
+++ b/libc/sysdeps/linux/mips/bits/siginfo.h
@@ -108,6 +108,14 @@ typedef struct siginfo
 	    long int si_band;	/* Band event for SIGPOLL.  */
 	    int si_fd;
 	  } _sigpoll;
+
+	/* SIGSYS.  */
+	struct
+	  {
+	    void *_call_addr;   /* Calling user insn.  */
+	    int _syscall;       /* Triggering system call number.  */
+	    unsigned int _arch; /* AUDIT_ARCH_* of syscall.  */
+	  } _sigsys;
       } _sifields;
   } siginfo_t;
 
@@ -127,6 +135,9 @@ typedef struct siginfo
 # define si_addr_lsb	_sifields._sigfault.si_addr_lsb
 # define si_band	_sifields._sigpoll.si_band
 # define si_fd		_sifields._sigpoll.si_fd
+# define si_call_addr	_sifields._sigsys._call_addr
+# define si_syscall	_sifields._sigsys._syscall
+# define si_arch	_sifields._sigsys._arch
 
 
 /* Values for `si_code'.  Positive values are reserved for kernel-generated
diff --git a/libc/sysdeps/linux/sparc/bits/siginfo.h b/libc/sysdeps/linux/sparc/bits/siginfo.h
index 3ffeb6dcf..da1c83884 100644
--- a/libc/sysdeps/linux/sparc/bits/siginfo.h
+++ b/libc/sysdeps/linux/sparc/bits/siginfo.h
@@ -104,6 +104,14 @@ typedef struct siginfo
 	    int si_band;	/* Band event for SIGPOLL.  */
 	    int si_fd;
 	  } _sigpoll;
+
+	/* SIGSYS.  */
+	struct
+	  {
+	    void *_call_addr;   /* Calling user insn.  */
+	    int _syscall;       /* Triggering system call number.  */
+	    unsigned int _arch; /* AUDIT_ARCH_* of syscall.  */
+	  } _sigsys;
       } _sifields;
   } siginfo_t;
 
@@ -123,6 +131,9 @@ typedef struct siginfo
 # define si_trapno	_sifields._sigfault.si_trapno
 # define si_band	_sifields._sigpoll.si_band
 # define si_fd		_sifields._sigpoll.si_fd
+# define si_call_addr	_sifields._sigsys._call_addr
+# define si_syscall	_sifields._sigsys._syscall
+# define si_arch	_sifields._sigsys._arch
 
 
 /* Values for `si_code'.  Positive values are reserved for kernel-generated