The Tor Browser: netwerk/sctp/src/user_malloc.h@97036ab72558 (annotated)

netwerk/sctp/src/user_malloc.h@97036ab72558 (annotated)

netwerk/sctp/src/user_malloc.h

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rwxr-xr-x

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /*-
  * Copyright (c) 1987, 1993
  *	The Regents of the University of California.
  * Copyright (c) 2005 Robert N. M. Watson
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  */
 /* This file has been renamed user_malloc.h for Userspace */
 #ifndef _USER_MALLOC_H_
 #define	_USER_MALLOC_H_
 /*__Userspace__*/
 #include <stdlib.h>
 #include <sys/types.h>
 #if !defined (__Userspace_os_Windows)
 #include <strings.h>
 #include <stdint.h>
 #else
 #include "netinet/sctp_os_userspace.h"
 #endif
 #define	MINALLOCSIZE	UMA_SMALLEST_UNIT
 /*
  * flags to malloc.
  */
 #define	M_NOWAIT	0x0001		/* do not block */
 #define	M_WAITOK	0x0002		/* ok to block */
 #define	M_ZERO		0x0100		/* bzero the allocation */
 #define	M_NOVM		0x0200		/* don't ask VM for pages */
 #define	M_USE_RESERVE	0x0400		/* can alloc out of reserve memory */
 #define	M_MAGIC		877983977	/* time when first defined :-) */
 /*
  * Two malloc type structures are present: malloc_type, which is used by a
  * type owner to declare the type, and malloc_type_internal, which holds
  * malloc-owned statistics and other ABI-sensitive fields, such as the set of
  * malloc statistics indexed by the compile-time MAXCPU constant.
  * Applications should avoid introducing dependence on the allocator private
  * data layout and size.
  *
  * The malloc_type ks_next field is protected by malloc_mtx.  Other fields in
  * malloc_type are static after initialization so unsynchronized.
  *
  * Statistics in malloc_type_stats are written only when holding a critical
  * section and running on the CPU associated with the index into the stat
  * array, but read lock-free resulting in possible (minor) races, which the
  * monitoring app should take into account.
  */
 struct malloc_type_stats {
 	uint64_t	mts_memalloced;	/* Bytes allocated on CPU. */
 	uint64_t	mts_memfreed;	/* Bytes freed on CPU. */
 	uint64_t	mts_numallocs;	/* Number of allocates on CPU. */
 	uint64_t	mts_numfrees;	/* number of frees on CPU. */
 	uint64_t	mts_size;	/* Bitmask of sizes allocated on CPU. */
 	uint64_t	_mts_reserved1;	/* Reserved field. */
 	uint64_t	_mts_reserved2;	/* Reserved field. */
 	uint64_t	_mts_reserved3;	/* Reserved field. */
 };
 #ifndef MAXCPU /* necessary on Linux */
 #define MAXCPU 4 /* arbitrary? */
 #endif
 struct malloc_type_internal {
 	struct malloc_type_stats	mti_stats[MAXCPU];
 };
 /*
  * ABI-compatible version of the old 'struct malloc_type', only all stats are
  * now malloc-managed in malloc-owned memory rather than in caller memory, so
  * as to avoid ABI issues.  The ks_next pointer is reused as a pointer to the
  * internal data handle.
  */
 struct malloc_type {
 	struct malloc_type *ks_next;	/* Next in global chain. */
 	u_long		 _ks_memuse;	/* No longer used. */
 	u_long		 _ks_size;	/* No longer used. */
 	u_long		 _ks_inuse;	/* No longer used. */
 	uint64_t	 _ks_calls;	/* No longer used. */
 	u_long		 _ks_maxused;	/* No longer used. */
 	u_long		 ks_magic;	/* Detect programmer error. */
 	const char	*ks_shortdesc;	/* Printable type name. */
 	/*
 	 * struct malloc_type was terminated with a struct mtx, which is no
 	 * longer required.  For ABI reasons, continue to flesh out the full
 	 * size of the old structure, but reuse the _lo_class field for our
 	 * internal data handle.
 	 */
 	void		*ks_handle;	/* Priv. data, was lo_class. */
 	const char	*_lo_name;
 	const char	*_lo_type;
 	u_int		 _lo_flags;
 	void		*_lo_list_next;
 	struct witness	*_lo_witness;
 	uintptr_t	 _mtx_lock;
 	u_int		 _mtx_recurse;
 };
 /*
  * Statistics structure headers for user space.  The kern.malloc sysctl
  * exposes a structure stream consisting of a stream header, then a series of
  * malloc type headers and statistics structures (quantity maxcpus).  For
  * convenience, the kernel will provide the current value of maxcpus at the
  * head of the stream.
  */
 #define	MALLOC_TYPE_STREAM_VERSION	0x00000001
 struct malloc_type_stream_header {
 	uint32_t	mtsh_version;	/* Stream format version. */
 	uint32_t	mtsh_maxcpus;	/* Value of MAXCPU for stream. */
 	uint32_t	mtsh_count;	/* Number of records. */
 	uint32_t	_mtsh_pad;	/* Pad/reserved field. */
 };
 #define	MALLOC_MAX_NAME	32
 struct malloc_type_header {
 	char				mth_name[MALLOC_MAX_NAME];
 };
 /* __Userspace__
 Notice that at places it uses ifdef _KERNEL. That line cannot be
 removed because it causes conflicts with malloc definition in
 /usr/include/malloc.h, which essentially says that malloc.h has
 been overridden by stdlib.h. We will need to use names like
 user_malloc.h for isolating kernel interface headers. using
 original names like malloc.h in a user_include header can be
 confusing, All userspace header files are being placed in ./user_include
 Better still to remove from user_include.h all irrelevant code such
 as that in the block starting with #ifdef _KERNEL. I am only leaving
 it in for the time being to see what functionality is in this file
 that kernel uses.
 Start copy: Copied code for __Userspace__ */
 #define	MALLOC_DEFINE(type, shortdesc, longdesc)			\
 	struct malloc_type type[1] = {					\
 		{ NULL, 0, 0, 0, 0, 0, M_MAGIC, shortdesc, NULL, NULL,	\
 		    NULL, 0, NULL, NULL, 0, 0 }				\
 	}
 /* Removed "extern" in __Userspace__ code */
 /* If we need to use MALLOC_DECLARE before using MALLOC then
    we have to remove extern.
      In /usr/include/sys/malloc.h there is this definition:
      #define    MALLOC_DECLARE(type) \
         extern struct malloc_type type[1]
      and loader is unable to find the extern malloc_type because
      it may be defined in one of kernel object files.
      It seems that MALLOC_DECLARE and MALLOC_DEFINE cannot be used at
      the same time for same "type" variable. Also, in Randall's architecture
      document, where it specifies O/S specific macros and functions, it says
      that the name in SCTP_MALLOC does not have to be used.
 */
 #define	MALLOC_DECLARE(type) \
 	extern struct malloc_type type[1]
 #define	FREE(addr, type) free((addr))
 /* changed definitions of MALLOC and FREE */
 /* Using memset if flag M_ZERO is specified. Todo: M_WAITOK and M_NOWAIT */
 #define	MALLOC(space, cast, size, type, flags)                          \
     ((space) = (cast)malloc((u_long)(size)));                           \
     do {								\
         if(flags & M_ZERO) {                                            \
 	  memset(space,0,size);                                         \
 	}								\
     } while (0);
 /* End copy: Copied code for __Userspace__ */
 #if 0
 #ifdef _KERNEL
 #define	MALLOC_DEFINE(type, shortdesc, longdesc)			\
 	struct malloc_type type[1] = {					\
 		{ NULL, 0, 0, 0, 0, 0, M_MAGIC, shortdesc, NULL, NULL,	\
 		    NULL, 0, NULL, NULL, 0, 0 }				\
 	};								\
 	SYSINIT(type##_init, SI_SUB_KMEM, SI_ORDER_SECOND, malloc_init,	\
 	    type);							\
 	SYSUNINIT(type##_uninit, SI_SUB_KMEM, SI_ORDER_ANY,		\
 	    malloc_uninit, type)
 #define	MALLOC_DECLARE(type) \
 	extern struct malloc_type type[1]
 MALLOC_DECLARE(M_CACHE);
 MALLOC_DECLARE(M_DEVBUF);
 MALLOC_DECLARE(M_TEMP);
 MALLOC_DECLARE(M_IP6OPT); /* for INET6 */
 MALLOC_DECLARE(M_IP6NDP); /* for INET6 */
 /*
  * Deprecated macro versions of not-quite-malloc() and free().
  */
 #define	MALLOC(space, cast, size, type, flags) \
 	((space) = (cast)malloc((u_long)(size), (type), (flags)))
 #define	FREE(addr, type) free((addr), (type))
 /*
  * XXX this should be declared in <sys/uio.h>, but that tends to fail
  * because <sys/uio.h> is included in a header before the source file
  * has a chance to include <sys/malloc.h> to get MALLOC_DECLARE() defined.
  */
 MALLOC_DECLARE(M_IOV);
 extern struct mtx malloc_mtx;
 /* XXX struct malloc_type is unused for contig*(). */
 void	contigfree(void *addr, unsigned long size, struct malloc_type *type);
 void	*contigmalloc(unsigned long size, struct malloc_type *type, int flags,
 	    vm_paddr_t low, vm_paddr_t high, unsigned long alignment,
 	    unsigned long boundary);
 void	free(void *addr, struct malloc_type *type);
 void	*malloc(unsigned long size, struct malloc_type *type, int flags);
 void	malloc_init(void *);
 int	malloc_last_fail(void);
 void	malloc_type_allocated(struct malloc_type *type, unsigned long size);
 void	malloc_type_freed(struct malloc_type *type, unsigned long size);
 void	malloc_uninit(void *);
 void	*realloc(void *addr, unsigned long size, struct malloc_type *type,
 	    int flags);
 void	*reallocf(void *addr, unsigned long size, struct malloc_type *type,
 	    int flags);
 #endif /* _KERNEL */
 #endif
 #endif /* !_SYS_MALLOC_H_ */

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netwerk/sctp/src/user_malloc.h@97036ab72558 (annotated)

netwerk/sctp/src/user_malloc.h