stackprotector: move get_random_canary() into stackprotector.h

This has nothing to do with random.c and everything to do with stack
protectors. Yes, it uses randomness. But many things use randomness.
random.h and random.c are concerned with the generation of randomness,
not with each and every use. So move this function into the more
specific stackprotector.h file where it belongs.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 3e508f23909830fd78fbd6b168ad04aaeb57ef18..3f66dd03c0919bf6a764aed2edbe8f5da5456091 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -22,9 +22,9 @@
 #include <linux/io.h>
 #include <linux/syscore_ops.h>
 #include <linux/pgtable.h>
+#include <linux/stackprotector.h>
 
 #include <asm/cmdline.h>
-#include <asm/stackprotector.h>
 #include <asm/perf_event.h>
 #include <asm/mmu_context.h>
 #include <asm/doublefault.h>

diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index 49325caa7307df8f5944b1ea2b32c8310d59c642..b26123c90b4fd3dca51f43aeaae46cbfde526295 100644 (file)
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -11,6 +11,7 @@
 #include <linux/smp.h>
 #include <linux/topology.h>
 #include <linux/pfn.h>
+#include <linux/stackprotector.h>
 #include <asm/sections.h>
 #include <asm/processor.h>
 #include <asm/desc.h>
@@ -21,7 +22,6 @@
 #include <asm/proto.h>
 #include <asm/cpumask.h>
 #include <asm/cpu.h>
-#include <asm/stackprotector.h>
 
 DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number);
 EXPORT_PER_CPU_SYMBOL(cpu_number);

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 3f3ea0287f694f6a5a674ef7d63c1b5f8839fbcb..5a742b6ec46d03ea38762f6e7841a5e0893dda6e 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -56,6 +56,7 @@
 #include <linux/numa.h>
 #include <linux/pgtable.h>
 #include <linux/overflow.h>
+#include <linux/stackprotector.h>
 
 #include <asm/acpi.h>
 #include <asm/desc.h>

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index f82857e488152a7377690f9d37a3a72e733c58d7..745420853a7cb5a72c046b3762c0ba0f922b5ce9 100644 (file)
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -32,6 +32,7 @@
 #include <linux/edd.h>
 #include <linux/reboot.h>
 #include <linux/virtio_anchor.h>
+#include <linux/stackprotector.h>
 
 #include <xen/xen.h>
 #include <xen/events.h>
@@ -64,7 +65,6 @@
 #include <asm/pgalloc.h>
 #include <asm/tlbflush.h>
 #include <asm/reboot.h>
-#include <asm/stackprotector.h>
 #include <asm/hypervisor.h>
 #include <asm/mach_traps.h>
 #include <asm/mwait.h>

diff --git a/include/linux/random.h b/include/linux/random.h
index bd954ecbef901756a021d5fdc1dc6a6a0c41544f..d1d680b9701d2dd832738bc6858ee4d26ca146a9 100644 (file)
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -116,25 +116,6 @@ static inline u32 get_random_u32_inclusive(u32 floor, u32 ceil)
        return floor + get_random_u32_below(ceil - floor + 1);
 }
 
-/*
- * On 64-bit architectures, protect against non-terminated C string overflows
- * by zeroing out the first byte of the canary; this leaves 56 bits of entropy.
- */
-#ifdef CONFIG_64BIT
-# ifdef __LITTLE_ENDIAN
-#  define CANARY_MASK 0xffffffffffffff00UL
-# else /* big endian, 64 bits: */
-#  define CANARY_MASK 0x00ffffffffffffffUL
-# endif
-#else /* 32 bits: */
-# define CANARY_MASK 0xffffffffUL
-#endif
-
-static inline unsigned long get_random_canary(void)
-{
-       return get_random_long() & CANARY_MASK;
-}
-
 void __init random_init_early(const char *command_line);
 void __init random_init(void);
 bool rng_is_initialized(void);

diff --git a/include/linux/stackprotector.h b/include/linux/stackprotector.h
index 4c678c4fec58e5f8ecb1f6184c41f0fbd2bf54d0..9c88707d9a0f5fac448d3a34a7153fe71951fcd0 100644 (file)
--- a/include/linux/stackprotector.h
+++ b/include/linux/stackprotector.h
@@ -6,6 +6,25 @@
 #include <linux/sched.h>
 #include <linux/random.h>
 
+/*
+ * On 64-bit architectures, protect against non-terminated C string overflows
+ * by zeroing out the first byte of the canary; this leaves 56 bits of entropy.
+ */
+#ifdef CONFIG_64BIT
+# ifdef __LITTLE_ENDIAN
+#  define CANARY_MASK 0xffffffffffffff00UL
+# else /* big endian, 64 bits: */
+#  define CANARY_MASK 0x00ffffffffffffffUL
+# endif
+#else /* 32 bits: */
+# define CANARY_MASK 0xffffffffUL
+#endif
+
+static inline unsigned long get_random_canary(void)
+{
+       return get_random_long() & CANARY_MASK;
+}
+
 #if defined(CONFIG_STACKPROTECTOR) || defined(CONFIG_ARM64_PTR_AUTH)
 # include <asm/stackprotector.h>
 #else

diff --git a/kernel/fork.c b/kernel/fork.c
index 08969f5aa38d5906b2f42f975054c62bc7f7bf80..ec57cae58ff1835a2e8f88a1d2a79b944eb9cb60 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -75,7 +75,6 @@
 #include <linux/freezer.h>
 #include <linux/delayacct.h>
 #include <linux/taskstats_kern.h>
-#include <linux/random.h>
 #include <linux/tty.h>
 #include <linux/fs_struct.h>
 #include <linux/magic.h>
@@ -97,6 +96,7 @@
 #include <linux/scs.h>
 #include <linux/io_uring.h>
 #include <linux/bpf.h>
+#include <linux/stackprotector.h>
 
 #include <asm/pgalloc.h>
 #include <linux/uaccess.h>