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-rw-r--r--lib/Kconfig.debug16
-rw-r--r--lib/Makefile2
-rw-r--r--lib/bitmap.c54
-rw-r--r--lib/random32.c142
4 files changed, 201 insertions, 13 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 756a908..77491e3 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -71,7 +71,7 @@ config LOG_BUF_SHIFT
config DETECT_SOFTLOCKUP
bool "Detect Soft Lockups"
- depends on DEBUG_KERNEL
+ depends on DEBUG_KERNEL && !S390
default y
help
Say Y here to enable the kernel to detect "soft lockups",
@@ -371,6 +371,20 @@ config FORCED_INLINING
become the default in the future, until then this option is there to
test gcc for this.
+config HEADERS_CHECK
+ bool "Run 'make headers_check' when building vmlinux"
+ depends on !UML
+ help
+ This option will extract the user-visible kernel headers whenever
+ building the kernel, and will run basic sanity checks on them to
+ ensure that exported files do not attempt to include files which
+ were not exported, etc.
+
+ If you're making modifications to header files which are
+ relevant for userspace, say 'Y', and check the headers
+ exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in
+ your build tree), to make sure they're suitable.
+
config RCU_TORTURE_TEST
tristate "torture tests for RCU"
depends on DEBUG_KERNEL
diff --git a/lib/Makefile b/lib/Makefile
index 8e6662b..cf98fab 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -12,7 +12,7 @@ lib-$(CONFIG_SMP) += cpumask.o
lib-y += kobject.o kref.o kobject_uevent.o klist.o
-obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o
+obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o random32.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG
diff --git a/lib/bitmap.c b/lib/bitmap.c
index d71e38c..037fa9a 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -316,10 +316,11 @@ int bitmap_scnprintf(char *buf, unsigned int buflen,
EXPORT_SYMBOL(bitmap_scnprintf);
/**
- * bitmap_parse - convert an ASCII hex string into a bitmap.
- * @ubuf: pointer to buffer in user space containing string.
- * @ubuflen: buffer size in bytes. If string is smaller than this
+ * __bitmap_parse - convert an ASCII hex string into a bitmap.
+ * @buf: pointer to buffer containing string.
+ * @buflen: buffer size in bytes. If string is smaller than this
* then it must be terminated with a \0.
+ * @is_user: location of buffer, 0 indicates kernel space
* @maskp: pointer to bitmap array that will contain result.
* @nmaskbits: size of bitmap, in bits.
*
@@ -330,11 +331,13 @@ EXPORT_SYMBOL(bitmap_scnprintf);
* characters and for grouping errors such as "1,,5", ",44", "," and "".
* Leading and trailing whitespace accepted, but not embedded whitespace.
*/
-int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
- unsigned long *maskp, int nmaskbits)
+int __bitmap_parse(const char *buf, unsigned int buflen,
+ int is_user, unsigned long *maskp,
+ int nmaskbits)
{
int c, old_c, totaldigits, ndigits, nchunks, nbits;
u32 chunk;
+ const char __user *ubuf = buf;
bitmap_zero(maskp, nmaskbits);
@@ -343,11 +346,15 @@ int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
chunk = ndigits = 0;
/* Get the next chunk of the bitmap */
- while (ubuflen) {
+ while (buflen) {
old_c = c;
- if (get_user(c, ubuf++))
- return -EFAULT;
- ubuflen--;
+ if (is_user) {
+ if (__get_user(c, ubuf++))
+ return -EFAULT;
+ }
+ else
+ c = *buf++;
+ buflen--;
if (isspace(c))
continue;
@@ -388,11 +395,36 @@ int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ;
if (nbits > nmaskbits)
return -EOVERFLOW;
- } while (ubuflen && c == ',');
+ } while (buflen && c == ',');
return 0;
}
-EXPORT_SYMBOL(bitmap_parse);
+EXPORT_SYMBOL(__bitmap_parse);
+
+/**
+ * bitmap_parse_user()
+ *
+ * @ubuf: pointer to user buffer containing string.
+ * @ulen: buffer size in bytes. If string is smaller than this
+ * then it must be terminated with a \0.
+ * @maskp: pointer to bitmap array that will contain result.
+ * @nmaskbits: size of bitmap, in bits.
+ *
+ * Wrapper for __bitmap_parse(), providing it with user buffer.
+ *
+ * We cannot have this as an inline function in bitmap.h because it needs
+ * linux/uaccess.h to get the access_ok() declaration and this causes
+ * cyclic dependencies.
+ */
+int bitmap_parse_user(const char __user *ubuf,
+ unsigned int ulen, unsigned long *maskp,
+ int nmaskbits)
+{
+ if (!access_ok(VERIFY_READ, ubuf, ulen))
+ return -EFAULT;
+ return __bitmap_parse((const char *)ubuf, ulen, 1, maskp, nmaskbits);
+}
+EXPORT_SYMBOL(bitmap_parse_user);
/*
* bscnl_emit(buf, buflen, rbot, rtop, bp)
diff --git a/lib/random32.c b/lib/random32.c
new file mode 100644
index 0000000..4a15ce5
--- /dev/null
+++ b/lib/random32.c
@@ -0,0 +1,142 @@
+/*
+ This is a maximally equidistributed combined Tausworthe generator
+ based on code from GNU Scientific Library 1.5 (30 Jun 2004)
+
+ x_n = (s1_n ^ s2_n ^ s3_n)
+
+ s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19))
+ s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25))
+ s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11))
+
+ The period of this generator is about 2^88.
+
+ From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe
+ Generators", Mathematics of Computation, 65, 213 (1996), 203--213.
+
+ This is available on the net from L'Ecuyer's home page,
+
+ http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
+ ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps
+
+ There is an erratum in the paper "Tables of Maximally
+ Equidistributed Combined LFSR Generators", Mathematics of
+ Computation, 68, 225 (1999), 261--269:
+ http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
+
+ ... the k_j most significant bits of z_j must be non-
+ zero, for each j. (Note: this restriction also applies to the
+ computer code given in [4], but was mistakenly not mentioned in
+ that paper.)
+
+ This affects the seeding procedure by imposing the requirement
+ s1 > 1, s2 > 7, s3 > 15.
+
+*/
+
+#include <linux/types.h>
+#include <linux/percpu.h>
+#include <linux/module.h>
+#include <linux/random.h>
+
+struct rnd_state {
+ u32 s1, s2, s3;
+};
+
+static DEFINE_PER_CPU(struct rnd_state, net_rand_state);
+
+static u32 __random32(struct rnd_state *state)
+{
+#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
+
+ state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
+ state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
+ state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
+
+ return (state->s1 ^ state->s2 ^ state->s3);
+}
+
+static void __set_random32(struct rnd_state *state, unsigned long s)
+{
+ if (s == 0)
+ s = 1; /* default seed is 1 */
+
+#define LCG(n) (69069 * n)
+ state->s1 = LCG(s);
+ state->s2 = LCG(state->s1);
+ state->s3 = LCG(state->s2);
+
+ /* "warm it up" */
+ __random32(state);
+ __random32(state);
+ __random32(state);
+ __random32(state);
+ __random32(state);
+ __random32(state);
+}
+
+/**
+ * random32 - pseudo random number generator
+ *
+ * A 32 bit pseudo-random number is generated using a fast
+ * algorithm suitable for simulation. This algorithm is NOT
+ * considered safe for cryptographic use.
+ */
+u32 random32(void)
+{
+ unsigned long r;
+ struct rnd_state *state = &get_cpu_var(net_rand_state);
+ r = __random32(state);
+ put_cpu_var(state);
+ return r;
+}
+EXPORT_SYMBOL(random32);
+
+/**
+ * srandom32 - add entropy to pseudo random number generator
+ * @seed: seed value
+ *
+ * Add some additional seeding to the random32() pool.
+ * Note: this pool is per cpu so it only affects current CPU.
+ */
+void srandom32(u32 entropy)
+{
+ struct rnd_state *state = &get_cpu_var(net_rand_state);
+ __set_random32(state, state->s1 ^ entropy);
+ put_cpu_var(state);
+}
+EXPORT_SYMBOL(srandom32);
+
+/*
+ * Generate some initially weak seeding values to allow
+ * to start the random32() engine.
+ */
+static int __init random32_init(void)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ struct rnd_state *state = &per_cpu(net_rand_state,i);
+ __set_random32(state, i + jiffies);
+ }
+ return 0;
+}
+core_initcall(random32_init);
+
+/*
+ * Generate better values after random number generator
+ * is fully initalized.
+ */
+static int __init random32_reseed(void)
+{
+ int i;
+ unsigned long seed;
+
+ for_each_possible_cpu(i) {
+ struct rnd_state *state = &per_cpu(net_rand_state,i);
+
+ get_random_bytes(&seed, sizeof(seed));
+ __set_random32(state, seed);
+ }
+ return 0;
+}
+late_initcall(random32_reseed);
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