Merge branch 'for-4.20-vsprintf-hash-fixes' into for-linus (54edeb03) · Commits · e / devices / android_kernel_fairphone_FP5

Documentation/core-api/printk-formats.rst

+2 −3

Original line number	Diff line number	Diff line
		@@ -420,9 +420,8 @@ struct clk
		%pC pll1
		%pCn pll1

		For printing struct clk structures. %pC and %pCn print the name
		(Common Clock Framework) or address (legacy clock framework) of the
		structure.
		For printing struct clk structures. %pC and %pCn print the name of the clock
		(Common Clock Framework) or a unique 32-bit ID (legacy clock framework).

		Passed by reference.

lib/vsprintf.c

+108 −108

Original line number	Diff line number	Diff line
		@@ -612,6 +612,109 @@ char string(char buf, char end, const char s, struct printf_spec spec)
		return widen_string(buf, len, end, spec);
		}

		static noinline_for_stack
		char pointer_string(char buf, char end, const void ptr,
		struct printf_spec spec)
		{
		spec.base = 16;
		spec.flags \|= SMALL;
		if (spec.field_width == -1) {
		spec.field_width = 2 * sizeof(ptr);
		spec.flags \|= ZEROPAD;
		}

		return number(buf, end, (unsigned long int)ptr, spec);
		}

		/* Make pointers available for printing early in the boot sequence. */
		static int debug_boot_weak_hash __ro_after_init;

		static int __init debug_boot_weak_hash_enable(char *str)
		{
		debug_boot_weak_hash = 1;
		pr_info("debug_boot_weak_hash enabled\n");
		return 0;
		}
		early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);

		static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
		static siphash_key_t ptr_key __read_mostly;

		static void enable_ptr_key_workfn(struct work_struct *work)
		{
		get_random_bytes(&ptr_key, sizeof(ptr_key));
		/* Needs to run from preemptible context */
		static_branch_disable(&not_filled_random_ptr_key);
		}

		static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);

		static void fill_random_ptr_key(struct random_ready_callback *unused)
		{
		/* This may be in an interrupt handler. */
		queue_work(system_unbound_wq, &enable_ptr_key_work);
		}

		static struct random_ready_callback random_ready = {
		.func = fill_random_ptr_key
		};

		static int __init initialize_ptr_random(void)
		{
		int key_size = sizeof(ptr_key);
		int ret;

		/* Use hw RNG if available. */
		if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
		static_branch_disable(&not_filled_random_ptr_key);
		return 0;
		}

		ret = add_random_ready_callback(&random_ready);
		if (!ret) {
		return 0;
		} else if (ret == -EALREADY) {
		/* This is in preemptible context */
		enable_ptr_key_workfn(&enable_ptr_key_work);
		return 0;
		}

		return ret;
		}
		early_initcall(initialize_ptr_random);

		/* Maps a pointer to a 32 bit unique identifier. */
		static char ptr_to_id(char buf, char end, const void ptr,
		struct printf_spec spec)
		{
		const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
		unsigned long hashval;

		/* When debugging early boot use non-cryptographically secure hash. */
		if (unlikely(debug_boot_weak_hash)) {
		hashval = hash_long((unsigned long)ptr, 32);
		return pointer_string(buf, end, (const void *)hashval, spec);
		}

		if (static_branch_unlikely(&not_filled_random_ptr_key)) {
		spec.field_width = 2 * sizeof(ptr);
		/* string length must be less than default_width */
		return string(buf, end, str, spec);
		}

		#ifdef CONFIG_64BIT
		hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
		/*
		* Mask off the first 32 bits, this makes explicit that we have
		* modified the address (and 32 bits is plenty for a unique ID).
		*/
		hashval = hashval & 0xffffffff;
		#else
		hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
		#endif
		return pointer_string(buf, end, (const void *)hashval, spec);
		}

		static noinline_for_stack
		char dentry_name(char buf, char end, const struct dentry d, struct printf_spec spec,
		const char *fmt)
		@@ -1357,20 +1460,6 @@ char uuid_string(char buf, char end, const u8 addr,
		return string(buf, end, uuid, spec);
		}

		static noinline_for_stack
		char pointer_string(char buf, char end, const void ptr,
		struct printf_spec spec)
		{
		spec.base = 16;
		spec.flags \|= SMALL;
		if (spec.field_width == -1) {
		spec.field_width = 2 * sizeof(ptr);
		spec.flags \|= ZEROPAD;
		}

		return number(buf, end, (unsigned long int)ptr, spec);
		}

		int kptr_restrict __read_mostly;

		static noinline_for_stack
		@@ -1421,7 +1510,8 @@ char restricted_pointer(char buf, char end, const void ptr,
		}

		static noinline_for_stack
		char netdev_bits(char buf, char end, const void addr, const char *fmt)
		char netdev_bits(char buf, char end, const void addr,
		struct printf_spec spec, const char *fmt)
		{
		unsigned long long num;
		int size;
		@@ -1432,9 +1522,7 @@ char netdev_bits(char buf, char end, const void addr, const char *fmt)
		size = sizeof(netdev_features_t);
		break;
		default:
		num = (unsigned long)addr;
		size = sizeof(unsigned long);
		break;
		return ptr_to_id(buf, end, addr, spec);
		}

		return special_hex_number(buf, end, num, size);
		@@ -1474,7 +1562,7 @@ char clock(char buf, char end, struct clk clk, struct printf_spec spec,
		#ifdef CONFIG_COMMON_CLK
		return string(buf, end, __clk_get_name(clk), spec);
		#else
		return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
		return ptr_to_id(buf, end, clk, spec);
		#endif
		}
		}
		@@ -1651,94 +1739,6 @@ char device_node_string(char buf, char end, struct device_node dn,
		return widen_string(buf, buf - buf_start, end, spec);
		}

		/* Make pointers available for printing early in the boot sequence. */
		static int debug_boot_weak_hash __ro_after_init;

		static int __init debug_boot_weak_hash_enable(char *str)
		{
		debug_boot_weak_hash = 1;
		pr_info("debug_boot_weak_hash enabled\n");
		return 0;
		}
		early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);

		static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
		static siphash_key_t ptr_key __read_mostly;

		static void enable_ptr_key_workfn(struct work_struct *work)
		{
		get_random_bytes(&ptr_key, sizeof(ptr_key));
		/* Needs to run from preemptible context */
		static_branch_disable(&not_filled_random_ptr_key);
		}

		static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);

		static void fill_random_ptr_key(struct random_ready_callback *unused)
		{
		/* This may be in an interrupt handler. */
		queue_work(system_unbound_wq, &enable_ptr_key_work);
		}

		static struct random_ready_callback random_ready = {
		.func = fill_random_ptr_key
		};

		static int __init initialize_ptr_random(void)
		{
		int key_size = sizeof(ptr_key);
		int ret;

		/* Use hw RNG if available. */
		if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
		static_branch_disable(&not_filled_random_ptr_key);
		return 0;
		}

		ret = add_random_ready_callback(&random_ready);
		if (!ret) {
		return 0;
		} else if (ret == -EALREADY) {
		/* This is in preemptible context */
		enable_ptr_key_workfn(&enable_ptr_key_work);
		return 0;
		}

		return ret;
		}
		early_initcall(initialize_ptr_random);

		/* Maps a pointer to a 32 bit unique identifier. */
		static char ptr_to_id(char buf, char end, void ptr, struct printf_spec spec)
		{
		const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
		unsigned long hashval;

		/* When debugging early boot use non-cryptographically secure hash. */
		if (unlikely(debug_boot_weak_hash)) {
		hashval = hash_long((unsigned long)ptr, 32);
		return pointer_string(buf, end, (const void *)hashval, spec);
		}

		if (static_branch_unlikely(&not_filled_random_ptr_key)) {
		spec.field_width = 2 * sizeof(ptr);
		/* string length must be less than default_width */
		return string(buf, end, str, spec);
		}

		#ifdef CONFIG_64BIT
		hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
		/*
		* Mask off the first 32 bits, this makes explicit that we have
		* modified the address (and 32 bits is plenty for a unique ID).
		*/
		hashval = hashval & 0xffffffff;
		#else
		hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
		#endif
		return pointer_string(buf, end, (const void *)hashval, spec);
		}

		/*
		* Show a '%p' thing. A kernel extension is that the '%p' is followed
		* by an extra set of alphanumeric characters that are extended format
		@@ -1944,7 +1944,7 @@ char pointer(const char fmt, char buf, char end, void *ptr,
		break;
		return restricted_pointer(buf, end, ptr, spec);
		case 'N':
		return netdev_bits(buf, end, ptr, fmt);
		return netdev_bits(buf, end, ptr, spec, fmt);
		case 'a':
		return address_val(buf, end, ptr, fmt);
		case 'd':