[PATCH] RLIM: add rlimit entry for controlling queued signals

The following patches introduce per user rlimits for both queued signals and
POSIX message queues.  The changes touch all the arches resource.h files as
well as init_task.c to get the rlimit defaults setup.

Both require caching the user_struct to avoid problems with setuid().

The signal changes makes some small changes to send_signal() to pass along the
task being signalled to get proper accounting for signals initiated in
interrupt.  Thanks to Marcelo for getting this one going.


This patch:

Add an rlimit entry to control the maximum number of pending signals a user
may have.  This is essentially just the resource.h changes.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-alpha/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_NPROC	8		/* max number of processes */
 #define RLIMIT_MEMLOCK	9		/* max locked-in-memory address space */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.  Fine, it's unsigned, but
@@ -41,6 +42,7 @@
     {LONG_MAX, LONG_MAX},			/* RLIMIT_NPROC */	\
     {LONG_MAX, LONG_MAX},			/* RLIMIT_MEMLOCK */	\
     {LONG_MAX, LONG_MAX},			/* RLIMIT_LOCKS */	\
+    {MAX_SIGPENDING, MAX_SIGPENDING},		/* RLIMIT_SIGPENDING */ \
 }
 
 #endif /* __KERNEL__ */

include/asm-arm/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 #ifdef __KERNEL__
 
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },	\
 	{ RLIM_INFINITY, RLIM_INFINITY },	\
 	{ RLIM_INFINITY, RLIM_INFINITY },	\
+	{ MAX_SIGPENDING, MAX_SIGPENDING},	\
 }
 
 #endif /* __KERNEL__ */

include/asm-arm26/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 #ifdef __KERNEL__
 
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },	\
 	{ RLIM_INFINITY, RLIM_INFINITY },	\
 	{ RLIM_INFINITY, RLIM_INFINITY },	\
+	{ MAX_SIGPENDING, MAX_SIGPENDING},	\
 }
 
 #endif /* __KERNEL__ */

include/asm-cris/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },               \
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-h8300/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-i386/resource.h

@@ -16,8 +16,10 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
+
+#define RLIM_NLIMITS	12
 
-#define RLIM_NLIMITS	11
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +42,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-ia64/resource.h

@@ -23,8 +23,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -47,6 +48,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 # endif /* __KERNEL__ */

include/asm-m68k/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-mips/resource.h

@@ -23,8 +23,9 @@
 #define RLIMIT_NPROC 8			/* max number of processes */
 #define RLIMIT_MEMLOCK 9		/* max locked-in-memory address space */
 #define RLIMIT_LOCKS 10			/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS 11			/* Number of limit flavors.  */
+#define RLIM_NLIMITS 12			/* Number of limit flavors.  */
 
 #ifdef __KERNEL__
 
@@ -54,6 +55,7 @@
 	{ 0,             0             },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-parisc/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-ppc/resource.h

@@ -12,8 +12,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit(?) */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 #ifdef __KERNEL__
 
@@ -37,6 +38,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-ppc64/resource.h

@@ -21,8 +21,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit(?) */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 #ifdef __KERNEL__
 
@@ -46,6 +47,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-s390/resource.h

@@ -24,8 +24,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -48,6 +49,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-sh/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 #ifdef __KERNEL__
 
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-sparc/resource.h

@@ -22,8 +22,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -44,7 +45,8 @@
     {INR_OPEN, INR_OPEN}, {0, 0},	\
     {RLIM_INFINITY, RLIM_INFINITY},	\
     {RLIM_INFINITY, RLIM_INFINITY},	\
-    {RLIM_INFINITY, RLIM_INFINITY}	\
+    {RLIM_INFINITY, RLIM_INFINITY},	\
+    {MAX_SIGPENDING, MAX_SIGPENDING},	\
 }
 
 #endif /* __KERNEL__ */

include/asm-sparc64/resource.h

@@ -22,8 +22,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -43,7 +44,8 @@
     {INR_OPEN, INR_OPEN}, {0, 0},	\
     {RLIM_INFINITY, RLIM_INFINITY},	\
     {RLIM_INFINITY, RLIM_INFINITY},	\
-    {RLIM_INFINITY, RLIM_INFINITY}	\
+    {RLIM_INFINITY, RLIM_INFINITY},	\
+    {MAX_SIGPENDING, MAX_SIGPENDING},	\
 }
 
 #endif /* __KERNEL__ */

include/asm-v850/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/asm-x86_64/resource.h

@@ -16,8 +16,9 @@
 #define RLIMIT_MEMLOCK	8		/* max locked-in-memory address space */
 #define RLIMIT_AS	9		/* address space limit */
 #define RLIMIT_LOCKS	10		/* maximum file locks held */
+#define RLIMIT_SIGPENDING 11		/* max number of pending signals */
 
-#define RLIM_NLIMITS	11
+#define RLIM_NLIMITS	12
 
 /*
  * SuS says limits have to be unsigned.
@@ -40,6 +41,7 @@
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
 	{ RLIM_INFINITY, RLIM_INFINITY },		\
+	{ MAX_SIGPENDING, MAX_SIGPENDING },		\
 }
 
 #endif /* __KERNEL__ */

include/linux/signal.h

@@ -7,6 +7,9 @@
 #include <asm/siginfo.h>
 
 #ifdef __KERNEL__
+
+#define MAX_SIGPENDING	1024
+
 /*
  * Real Time signals may be queued.
  */