Fix lhash implementation to avoid unwanted resizes during iteration.

patches.chromium/0006-fix_lhash_iteration.patch

Index: patches.chromium/0006-fix_lhash_iteration.patch
diff --git a/patches.chromium/0006-fix_lhash_iteration.patch b/patches.chromium/0006-fix_lhash_iteration.patch
new file mode 100644
index 0000000000000000000000000000000000000000..c00b60acc997fab9952d19ff21a869a86407fe8c
--- /dev/null
+++ b/patches.chromium/0006-fix_lhash_iteration.patch
@@ -0,0 +1,320 @@
+diff -burN android-openssl.org/openssl.config android-openssl/openssl.config
+--- android-openssl.org/openssl.config	2013-11-05 10:26:23.008411507 +0100
++++ android-openssl/openssl.config	2013-11-05 10:28:13.409668262 +0100
+@@ -997,6 +997,7 @@
+ fix_clang_build.patch \
+ x509_hash_name_algorithm_change.patch \
+ reduce_client_hello_size.patch \
++fix_lhash_iteration.patch \
+ "
+ 
+ OPENSSL_PATCHES_progs_SOURCES="\
+@@ -1060,3 +1061,13 @@
+ OPENSSL_PATCHES_reduce_client_hello_size_SOURCES="\
+ ssl/t1_lib.c \
+ "
++
++OPENSSL_PATCHES_fix_lhash_iteration_SOURCES="\
++crypto/conf/conf_api.c
++crypto/lhash/lhash.c
++crypto/lhash/lhash.h
++crypto/objects/o_names.c
++crypto/objects/obj_dat.c
++include/openssl/lhash.h
++ssl/ssl_sess.c
++"
+diff -burN android-openssl.org/patches/fix_lhash_iteration.patch android-openssl/patches/fix_lhash_iteration.patch
+--- android-openssl.org/patches/fix_lhash_iteration.patch	1970-01-01 01:00:00.000000000 +0100
++++ android-openssl/patches/fix_lhash_iteration.patch	2013-11-05 10:26:40.678612658 +0100
+@@ -0,0 +1,291 @@
++diff --git a/crypto/conf/conf_api.c b/crypto/conf/conf_api.c
++index f5fcbb9..9a37bd4 100644
++--- a/crypto/conf/conf_api.c
+++++ b/crypto/conf/conf_api.c
++@@ -225,9 +225,6 @@ void _CONF_free_data(CONF *conf)
++ 	{
++ 	if (conf == NULL || conf->data == NULL) return;
++ 
++-	lh_CONF_VALUE_down_load(conf->data)=0; /* evil thing to make
++-				  * sure the 'OPENSSL_free()' works as
++-				  * expected */
++ 	lh_CONF_VALUE_doall_arg(conf->data,
++ 				LHASH_DOALL_ARG_FN(value_free_hash),
++ 				LHASH_OF(CONF_VALUE), conf->data);
++diff --git a/crypto/lhash/lhash.c b/crypto/lhash/lhash.c
++index 47f7480..e5b3cdf 100644
++--- a/crypto/lhash/lhash.c
+++++ b/crypto/lhash/lhash.c
++@@ -94,6 +94,7 @@
++  *
++  * 1.0 eay - First version
++  */
+++#include <limits.h>
++ #include <stdio.h>
++ #include <string.h>
++ #include <stdlib.h>
++@@ -107,6 +108,113 @@ const char lh_version[]="lhash" OPENSSL_VERSION_PTEXT;
++ #define UP_LOAD		(2*LH_LOAD_MULT) /* load times 256  (default 2) */
++ #define DOWN_LOAD	(LH_LOAD_MULT)   /* load times 256  (default 1) */
++ 
+++/* Maximum number of nodes to guarantee the load computations don't overflow */
+++#define MAX_LOAD_ITEMS   (UINT_MAX / LH_LOAD_MULT)
+++
+++/* The field 'iteration_state' is used to hold data to ensure that a hash
+++ * table is not resized during an 'insert' or 'delete' operation performed
+++ * within a lh_doall/lh_doall_arg call.
+++ *
+++ * Conceptually, this records two things:
+++ *
+++ *   - A 'depth' count, which is incremented at the start of lh_doall*,
+++ *     and decremented just before it returns.
+++ *
+++ *   - A 'mutated' boolean flag, which is set in lh_insert() or lh_delete()
+++ *     when the operation is performed with a non-0 depth.
+++ *
+++ * The following are helper macros to handle this state in a more explicit
+++ * way.
+++ */
+++
+++/* Reset the iteration state to its defaults. */
+++#define LH_ITERATION_RESET(lh) do { \
+++	(lh)->iteration_state = 0; \
+++	} while (0)
+++
+++/* Returns 1 if the hash table is currently being iterated on, 0 otherwise. */
+++#define LH_ITERATION_IS_ACTIVE(lh)  ((lh)->iteration_state >= 2)
+++
+++/* Increment iteration depth. This should always be followed by a paired call
+++ * to LH_ITERATION_DECREMENT_DEPTH(). */
+++#define LH_ITERATION_INCREMENT_DEPTH(lh) do { \
+++	(lh)->iteration_state += 2; \
+++	} while (0)
+++
+++/* Decrement iteration depth. This should always be called after a paired call
+++ * to LH_ITERATION_INCREMENT_DEPTH(). */
+++#define LH_ITERATION_DECREMENT_DEPTH(lh) do { \
+++	(lh)->iteration_state -= 2; \
+++	} while (0)
+++
+++/* Return 1 if the iteration 'mutated' flag is set, 0 otherwise. */
+++#define LH_ITERATION_IS_MUTATED(lh) (((lh)->iteration_state & 1) != 0)
+++
+++/* Set the iteration 'mutated' flag to 1. LH_ITERATION_RESET() to reset it. */
+++#define LH_ITERATION_SET_MUTATED(lh) do { \
+++	(lh)->iteration_state |= 1; \
+++	} while (0)
+++
+++/* This macro returns 1 if the hash table should be expanded due to its current
+++ * load, or 0 otherwise. The exact comparison to be performed is expressed by
+++ * the mathematical expression (where '//' denotes division over real numbers):
+++ *
+++ *      (num_items // num_nodes) >= (up_load // LOAD_MULT)    or
+++ *      (num_items * LOAD_MULT // num_nodes) >= up_load.
+++ *
+++ * Given that the C language operator '/' implements integer division, i.e:
+++ *     a // b == (a / b) + epsilon  (with 0 <= epsilon < 1, for positive a & b)
+++ *
+++ * This can be rewritten as:
+++ *     (num_items * LOAD_MULT / num_nodes) + epsilon >= up_load
+++ *     (num_items * LOAD_MULT / num_nodes) - up_load >= - epsilon
+++ *
+++ * Let's call 'A' the left-hand side of the equation above, it is an integer
+++ * and:
+++ *     - If A >= 0, the expression is true for any value of epsilon.
+++ *     - If A <= -1, the expression is also true for any value of epsilon.
+++ *
+++ * In other words, this is equivalent to 'A >= 0', or:
+++ *     (num_items * LOAD_MULT / num_nodes) >= up_load
+++ */
+++#define LH_SHOULD_EXPAND(lh) \
+++	((lh)->num_items < MAX_LOAD_ITEMS && \
+++	 (((lh)->num_items*LH_LOAD_MULT/(lh)->num_nodes) >= (lh)->up_load))
+++
+++/* This macro returns 1 if the hash table should be contracted due to its
+++ * current load, or 0 otherwise. Abbreviated computations are:
+++ *
+++ *    (num_items // num_nodes) <= (down_load // LOAD_MULT)
+++ *    (num_items * LOAD_MULT // num_nodes) <= down_load
+++ *    (num_items * LOAD_MULT / num_nodes) + epsilon <= down_load
+++ *    (num_items * LOAD_MULT / num_nodes) - down_load <= -epsilon
+++ *
+++ * Let's call 'B' the left-hand side of the equation above:
+++ *    - If B <= -1, the expression is true for any value of epsilon.
+++ *    - If B >= 1, the expression is false for any value of epsilon.
+++ *    - If B == 0, the expression is true for 'epsilon == 0', and false
+++ *      otherwise, which is problematic.
+++ *
+++ * To work around this problem, while keeping the code simple, just change
+++ * the initial expression to use a strict inequality, i.e.:
+++ *
+++ *    (num_items // num_nodes) < (down_load // LOAD_MULT)
+++ *
+++ * Which leads to:
+++ *    (num_items * LOAD_MULT / num_nodes) - down_load < -epsilon
+++ *
+++ * Then:
+++ *    - If 'B <= -1', the expression is true for any value of epsilon.
+++ *    - If 'B' >= 0, the expression is false for any value of epsilon,
+++ *
+++ * In other words, this is equivalent to 'B < 0', or:
+++ *     (num_items * LOAD_MULT / num_nodes) < down_load
+++ */
+++#define LH_SHOULD_CONTRACT(lh) \
+++	(((lh)->num_nodes > MIN_NODES) && \
+++	 ((lh)->num_items < MAX_LOAD_ITEMS && \
+++	 ((lh)->num_items*LH_LOAD_MULT/(lh)->num_nodes) < (lh)->down_load))
+++
++ static void expand(_LHASH *lh);
++ static void contract(_LHASH *lh);
++ static LHASH_NODE **getrn(_LHASH *lh, const void *data, unsigned long *rhash);
++@@ -147,6 +255,7 @@ _LHASH *lh_new(LHASH_HASH_FN_TYPE h, LHASH_COMP_FN_TYPE c)
++ 	ret->num_hash_comps=0;
++ 
++ 	ret->error=0;
+++	LH_ITERATION_RESET(ret);
++ 	return(ret);
++ err1:
++ 	OPENSSL_free(ret);
++@@ -183,7 +292,10 @@ void *lh_insert(_LHASH *lh, void *data)
++ 	void *ret;
++ 
++ 	lh->error=0;
++-	if (lh->up_load <= (lh->num_items*LH_LOAD_MULT/lh->num_nodes))
+++	/* Do not expand the array if the table is being iterated on. */
+++	if (LH_ITERATION_IS_ACTIVE(lh))
+++		LH_ITERATION_SET_MUTATED(lh);
+++	else if (LH_SHOULD_EXPAND(lh))
++ 		expand(lh);
++ 
++ 	rn=getrn(lh,data,&hash);
++@@ -238,8 +350,10 @@ void *lh_delete(_LHASH *lh, const void *data)
++ 		}
++ 
++ 	lh->num_items--;
++-	if ((lh->num_nodes > MIN_NODES) &&
++-		(lh->down_load >= (lh->num_items*LH_LOAD_MULT/lh->num_nodes)))
+++	/* Do not contract the array if the table is being iterated on. */
+++	if (LH_ITERATION_IS_ACTIVE(lh))
+++		LH_ITERATION_SET_MUTATED(lh);
+++	else if (LH_SHOULD_CONTRACT(lh))
++ 		contract(lh);
++ 
++ 	return(ret);
++@@ -276,6 +390,7 @@ static void doall_util_fn(_LHASH *lh, int use_arg, LHASH_DOALL_FN_TYPE func,
++ 	if (lh == NULL)
++ 		return;
++ 
+++	LH_ITERATION_INCREMENT_DEPTH(lh);
++ 	/* reverse the order so we search from 'top to bottom'
++ 	 * We were having memory leaks otherwise */
++ 	for (i=lh->num_nodes-1; i>=0; i--)
++@@ -283,10 +398,7 @@ static void doall_util_fn(_LHASH *lh, int use_arg, LHASH_DOALL_FN_TYPE func,
++ 		a=lh->b[i];
++ 		while (a != NULL)
++ 			{
++-			/* 28/05/91 - eay - n added so items can be deleted
++-			 * via lh_doall */
++-			/* 22/05/08 - ben - eh? since a is not passed,
++-			 * this should not be needed */
+++			/* note that 'a' can be deleted by the callback */
++ 			n=a->next;
++ 			if(use_arg)
++ 				func_arg(a->data,arg);
++@@ -295,6 +407,19 @@ static void doall_util_fn(_LHASH *lh, int use_arg, LHASH_DOALL_FN_TYPE func,
++ 			a=n;
++ 			}
++ 		}
+++
+++	LH_ITERATION_DECREMENT_DEPTH(lh);
+++	if (!LH_ITERATION_IS_ACTIVE(lh) && LH_ITERATION_IS_MUTATED(lh))
+++		{
+++		LH_ITERATION_RESET(lh);
+++		/* Resize the buckets array if necessary. Each expand() or
+++		 * contract() call will double/halve the size of the array,
+++		 * respectively, so call them in a loop. */
+++		while (LH_SHOULD_EXPAND(lh))
+++			expand(lh);
+++		while (LH_SHOULD_CONTRACT(lh))
+++			contract(lh);
+++		}
++ 	}
++ 
++ void lh_doall(_LHASH *lh, LHASH_DOALL_FN_TYPE func)
++diff --git a/crypto/lhash/lhash.h b/crypto/lhash/lhash.h
++index e7d8763..75386f2 100644
++--- a/crypto/lhash/lhash.h
+++++ b/crypto/lhash/lhash.h
++@@ -163,6 +163,7 @@ typedef struct lhash_st
++ 	unsigned long num_hash_comps;
++ 
++ 	int error;
+++	int iteration_state;
++ 	} _LHASH;	/* Do not use _LHASH directly, use LHASH_OF
++ 			 * and friends */
++ 
++diff --git a/crypto/objects/o_names.c b/crypto/objects/o_names.c
++index 4a548c2..4e18045 100644
++--- a/crypto/objects/o_names.c
+++++ b/crypto/objects/o_names.c
++@@ -350,13 +350,9 @@ static void name_funcs_free(NAME_FUNCS *ptr)
++ 
++ void OBJ_NAME_cleanup(int type)
++ 	{
++-	unsigned long down_load;
++-
++ 	if (names_lh == NULL) return;
++ 
++ 	free_type=type;
++-	down_load=lh_OBJ_NAME_down_load(names_lh);
++-	lh_OBJ_NAME_down_load(names_lh)=0;
++ 
++ 	lh_OBJ_NAME_doall(names_lh,LHASH_DOALL_FN(names_lh_free));
++ 	if (type < 0)
++@@ -366,7 +362,5 @@ void OBJ_NAME_cleanup(int type)
++ 		names_lh=NULL;
++ 		name_funcs_stack = NULL;
++ 		}
++-	else
++-		lh_OBJ_NAME_down_load(names_lh)=down_load;
++ 	}
++ 
++diff --git a/crypto/objects/obj_dat.c b/crypto/objects/obj_dat.c
++index 8a342ba..ef0512a 100644
++--- a/crypto/objects/obj_dat.c
+++++ b/crypto/objects/obj_dat.c
++@@ -227,7 +227,6 @@ void OBJ_cleanup(void)
++ 		return ;
++ 		}
++ 	if (added == NULL) return;
++-	lh_ADDED_OBJ_down_load(added) = 0;
++ 	lh_ADDED_OBJ_doall(added,LHASH_DOALL_FN(cleanup1)); /* zero counters */
++ 	lh_ADDED_OBJ_doall(added,LHASH_DOALL_FN(cleanup2)); /* set counters */
++ 	lh_ADDED_OBJ_doall(added,LHASH_DOALL_FN(cleanup3)); /* free objects */
++diff --git a/include/openssl/lhash.h b/include/openssl/lhash.h
++index e7d8763..75386f2 100644
++--- a/include/openssl/lhash.h
+++++ b/include/openssl/lhash.h
++@@ -163,6 +163,7 @@ typedef struct lhash_st
++ 	unsigned long num_hash_comps;
++ 
++ 	int error;
+++	int iteration_state;
++ 	} _LHASH;	/* Do not use _LHASH directly, use LHASH_OF
++ 			 * and friends */
++ 
++diff --git a/ssl/ssl_sess.c b/ssl/ssl_sess.c
++index 920b763..447a37e 100644
++--- a/ssl/ssl_sess.c
+++++ b/ssl/ssl_sess.c
++@@ -999,11 +999,8 @@ void SSL_CTX_flush_sessions(SSL_CTX *s, long t)
++ 	if (tp.cache == NULL) return;
++ 	tp.time=t;
++ 	CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
++-	i=CHECKED_LHASH_OF(SSL_SESSION, tp.cache)->down_load;
++-	CHECKED_LHASH_OF(SSL_SESSION, tp.cache)->down_load=0;
++ 	lh_SSL_SESSION_doall_arg(tp.cache, LHASH_DOALL_ARG_FN(timeout),
++ 				 TIMEOUT_PARAM, &tp);
++-	CHECKED_LHASH_OF(SSL_SESSION, tp.cache)->down_load=i;
++ 	CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
++ 	}
++