--- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -125,21 +125,26 @@ * The current exported interfaces for gathering environmental noise * from the devices are: * + * void add_device_randomness(const void *buf, unsigned int size); * void add_input_randomness(unsigned int type, unsigned int code, * unsigned int value); - * void add_interrupt_randomness(int irq); + * void add_interrupt_randomness(int irq, int irq_flags); * void add_disk_randomness(struct gendisk *disk); * * add_input_randomness() uses the input layer interrupt timing, as well as * the event type information from the hardware. * - * add_interrupt_randomness() uses the inter-interrupt timing as random - * inputs to the entropy pool. Note that not all interrupts are good - * sources of randomness! For example, the timer interrupts is not a - * good choice, because the periodicity of the interrupts is too - * regular, and hence predictable to an attacker. Network Interface - * Controller interrupts are a better measure, since the timing of the - * NIC interrupts are more unpredictable. + * add_interrupt_randomness() uses the interrupt timing as random + * inputs to the entropy pool. Using the cycle counters and the irq source + * as inputs, it feeds the randomness roughly once a second. + * + * add_device_randomness() is for adding data to the random pool that + * is likely to differ between two devices (or possibly even per boot). + * This would be things like MAC addresses or serial numbers, or the + * read-out of the RTC. This does *not* add any actual entropy to the + * pool, but it initializes the pool to different values for devices + * that might otherwise be identical and have very little entropy + * available to them (particularly common in the embedded world). * * add_disk_randomness() uses what amounts to the seek time of block * layer request events, on a per-disk_devt basis, as input to the @@ -248,6 +253,7 @@ #include #include #include +#include #ifdef CONFIG_GENERIC_HARDIRQS # include @@ -256,8 +262,12 @@ #include #include #include +#include #include +#define CREATE_TRACE_POINTS +#include + /* * Configuration information */ @@ -420,8 +430,10 @@ struct entropy_store { /* read-write data: */ spinlock_t lock; unsigned add_ptr; + unsigned input_rotate; int entropy_count; - int input_rotate; + int entropy_total; + unsigned int initialized:1; __u8 last_data[EXTRACT_SIZE]; }; @@ -454,6 +466,10 @@ static struct entropy_store nonblocking_ .pool = nonblocking_pool_data }; +static __u32 const twist_table[8] = { + 0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158, + 0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 }; + /* * This function adds bytes into the entropy "pool". It does not * update the entropy estimate. The caller should call @@ -464,29 +480,24 @@ static struct entropy_store nonblocking_ * it's cheap to do so and helps slightly in the expected case where * the entropy is concentrated in the low-order bits. */ -static void mix_pool_bytes_extract(struct entropy_store *r, const void *in, - int nbytes, __u8 out[64]) +static void _mix_pool_bytes(struct entropy_store *r, const void *in, + int nbytes, __u8 out[64]) { - static __u32 const twist_table[8] = { - 0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158, - 0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 }; unsigned long i, j, tap1, tap2, tap3, tap4, tap5; int input_rotate; int wordmask = r->poolinfo->poolwords - 1; const char *bytes = in; __u32 w; - unsigned long flags; - /* Taps are constant, so we can load them without holding r->lock. */ tap1 = r->poolinfo->tap1; tap2 = r->poolinfo->tap2; tap3 = r->poolinfo->tap3; tap4 = r->poolinfo->tap4; tap5 = r->poolinfo->tap5; - spin_lock_irqsave(&r->lock, flags); - input_rotate = r->input_rotate; - i = r->add_ptr; + smp_rmb(); + input_rotate = ACCESS_ONCE(r->input_rotate); + i = ACCESS_ONCE(r->add_ptr); /* mix one byte at a time to simplify size handling and churn faster */ while (nbytes--) { @@ -513,19 +524,61 @@ static void mix_pool_bytes_extract(struc input_rotate += i ? 7 : 14; } - r->input_rotate = input_rotate; - r->add_ptr = i; + ACCESS_ONCE(r->input_rotate) = input_rotate; + ACCESS_ONCE(r->add_ptr) = i; + smp_wmb(); if (out) for (j = 0; j < 16; j++) ((__u32 *)out)[j] = r->pool[(i - j) & wordmask]; +} + +static void __mix_pool_bytes(struct entropy_store *r, const void *in, + int nbytes, __u8 out[64]) +{ + trace_mix_pool_bytes_nolock(r->name, nbytes, _RET_IP_); + _mix_pool_bytes(r, in, nbytes, out); +} +static void mix_pool_bytes(struct entropy_store *r, const void *in, + int nbytes, __u8 out[64]) +{ + unsigned long flags; + + trace_mix_pool_bytes(r->name, nbytes, _RET_IP_); + spin_lock_irqsave(&r->lock, flags); + _mix_pool_bytes(r, in, nbytes, out); spin_unlock_irqrestore(&r->lock, flags); } -static void mix_pool_bytes(struct entropy_store *r, const void *in, int bytes) +struct fast_pool { + __u32 pool[4]; + unsigned long last; + unsigned short count; + unsigned char rotate; + unsigned char last_timer_intr; +}; + +/* + * This is a fast mixing routine used by the interrupt randomness + * collector. It's hardcoded for an 128 bit pool and assumes that any + * locks that might be needed are taken by the caller. + */ +static void fast_mix(struct fast_pool *f, const void *in, int nbytes) { - mix_pool_bytes_extract(r, in, bytes, NULL); + const char *bytes = in; + __u32 w; + unsigned i = f->count; + unsigned input_rotate = f->rotate; + + while (nbytes--) { + w = rol32(*bytes++, input_rotate & 31) ^ f->pool[i & 3] ^ + f->pool[(i + 1) & 3]; + f->pool[i & 3] = (w >> 3) ^ twist_table[w & 7]; + input_rotate += (i++ & 3) ? 7 : 14; + } + f->count = i; + f->rotate = input_rotate; } /* @@ -533,30 +586,38 @@ static void mix_pool_bytes(struct entrop */ static void credit_entropy_bits(struct entropy_store *r, int nbits) { - unsigned long flags; - int entropy_count; + int entropy_count, orig; if (!nbits) return; - spin_lock_irqsave(&r->lock, flags); - DEBUG_ENT("added %d entropy credits to %s\n", nbits, r->name); - entropy_count = r->entropy_count; +retry: + entropy_count = orig = ACCESS_ONCE(r->entropy_count); entropy_count += nbits; + if (entropy_count < 0) { DEBUG_ENT("negative entropy/overflow\n"); entropy_count = 0; } else if (entropy_count > r->poolinfo->POOLBITS) entropy_count = r->poolinfo->POOLBITS; - r->entropy_count = entropy_count; + if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig) + goto retry; + + if (!r->initialized && nbits > 0) { + r->entropy_total += nbits; + if (r->entropy_total > 128) + r->initialized = 1; + } + + trace_credit_entropy_bits(r->name, nbits, entropy_count, + r->entropy_total, _RET_IP_); /* should we wake readers? */ if (r == &input_pool && entropy_count >= random_read_wakeup_thresh) { wake_up_interruptible(&random_read_wait); kill_fasync(&fasync, SIGIO, POLL_IN); } - spin_unlock_irqrestore(&r->lock, flags); } /********************************************************************* @@ -609,6 +670,25 @@ static void set_timer_rand_state(unsigne } #endif +/* + * Add device- or boot-specific data to the input and nonblocking + * pools to help initialize them to unique values. + * + * None of this adds any entropy, it is meant to avoid the + * problem of the nonblocking pool having similar initial state + * across largely identical devices. + */ +void add_device_randomness(const void *buf, unsigned int size) +{ + unsigned long time = get_cycles() ^ jiffies; + + mix_pool_bytes(&input_pool, buf, size, NULL); + mix_pool_bytes(&input_pool, &time, sizeof(time), NULL); + mix_pool_bytes(&nonblocking_pool, buf, size, NULL); + mix_pool_bytes(&nonblocking_pool, &time, sizeof(time), NULL); +} +EXPORT_SYMBOL(add_device_randomness); + static struct timer_rand_state input_timer_state; /* @@ -637,13 +717,9 @@ static void add_timer_randomness(struct goto out; sample.jiffies = jiffies; - - /* Use arch random value, fall back to cycles */ - if (!arch_get_random_int(&sample.cycles)) - sample.cycles = get_cycles(); - + sample.cycles = get_cycles(); sample.num = num; - mix_pool_bytes(&input_pool, &sample, sizeof(sample)); + mix_pool_bytes(&input_pool, &sample, sizeof(sample), NULL); /* * Calculate number of bits of randomness we probably added. @@ -700,17 +776,48 @@ void add_input_randomness(unsigned int t } EXPORT_SYMBOL_GPL(add_input_randomness); -void add_interrupt_randomness(int irq) +static DEFINE_PER_CPU(struct fast_pool, irq_randomness); + +void add_interrupt_randomness(int irq, int irq_flags) { - struct timer_rand_state *state; + struct entropy_store *r; + struct fast_pool *fast_pool = &__get_cpu_var(irq_randomness); + struct pt_regs *regs = get_irq_regs(); + unsigned long now = jiffies; + __u32 input[4], cycles = get_cycles(); + + input[0] = cycles ^ jiffies; + input[1] = irq; + if (regs) { + __u64 ip = instruction_pointer(regs); + input[2] = ip; + input[3] = ip >> 32; + } - state = get_timer_rand_state(irq); + fast_mix(fast_pool, input, sizeof(input)); - if (state == NULL) + if ((fast_pool->count & 1023) && + !time_after(now, fast_pool->last + HZ)) return; - DEBUG_ENT("irq event %d\n", irq); - add_timer_randomness(state, 0x100 + irq); + fast_pool->last = now; + + r = nonblocking_pool.initialized ? &input_pool : &nonblocking_pool; + __mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL); + /* + * If we don't have a valid cycle counter, and we see + * back-to-back timer interrupts, then skip giving credit for + * any entropy. + */ + if (cycles == 0) { + if (irq_flags & __IRQF_TIMER) { + if (fast_pool->last_timer_intr) + return; + fast_pool->last_timer_intr = 1; + } else + fast_pool->last_timer_intr = 0; + } + credit_entropy_bits(r, 1); } #ifdef CONFIG_BLOCK @@ -742,7 +849,11 @@ static ssize_t extract_entropy(struct en */ static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes) { - __u32 tmp[OUTPUT_POOL_WORDS]; + union { + __u32 tmp[OUTPUT_POOL_WORDS]; + long hwrand[4]; + } u; + int i; if (r->pull && r->entropy_count < nbytes * 8 && r->entropy_count < r->poolinfo->POOLBITS) { @@ -753,17 +864,22 @@ static void xfer_secondary_pool(struct e /* pull at least as many as BYTES as wakeup BITS */ bytes = max_t(int, bytes, random_read_wakeup_thresh / 8); /* but never more than the buffer size */ - bytes = min_t(int, bytes, sizeof(tmp)); + bytes = min_t(int, bytes, sizeof(u.tmp)); DEBUG_ENT("going to reseed %s with %d bits " "(%d of %d requested)\n", r->name, bytes * 8, nbytes * 8, r->entropy_count); - bytes = extract_entropy(r->pull, tmp, bytes, + bytes = extract_entropy(r->pull, u.tmp, bytes, random_read_wakeup_thresh / 8, rsvd); - mix_pool_bytes(r, tmp, bytes); + mix_pool_bytes(r, u.tmp, bytes, NULL); credit_entropy_bits(r, bytes*8); } + for (i = 0; i < 4; i++) + if (arch_get_random_long(&u.hwrand[i])) + break; + if (i) + mix_pool_bytes(r, &u.hwrand, i * sizeof(u.hwrand[0]), 0); } /* @@ -822,9 +938,11 @@ static void extract_buf(struct entropy_s int i; __u32 hash[5], workspace[SHA_WORKSPACE_WORDS]; __u8 extract[64]; + unsigned long flags; /* Generate a hash across the pool, 16 words (512 bits) at a time */ sha_init(hash); + spin_lock_irqsave(&r->lock, flags); for (i = 0; i < r->poolinfo->poolwords; i += 16) sha_transform(hash, (__u8 *)(r->pool + i), workspace); @@ -837,7 +955,8 @@ static void extract_buf(struct entropy_s * brute-forcing the feedback as hard as brute-forcing the * hash. */ - mix_pool_bytes_extract(r, hash, sizeof(hash), extract); + __mix_pool_bytes(r, hash, sizeof(hash), extract); + spin_unlock_irqrestore(&r->lock, flags); /* * To avoid duplicates, we atomically extract a portion of the @@ -860,12 +979,12 @@ static void extract_buf(struct entropy_s } static ssize_t extract_entropy(struct entropy_store *r, void *buf, - size_t nbytes, int min, int reserved) + size_t nbytes, int min, int reserved) { ssize_t ret = 0, i; __u8 tmp[EXTRACT_SIZE]; - unsigned long flags; + trace_extract_entropy(r->name, nbytes, r->entropy_count, _RET_IP_); xfer_secondary_pool(r, nbytes); nbytes = account(r, nbytes, min, reserved); @@ -873,6 +992,8 @@ static ssize_t extract_entropy(struct en extract_buf(r, tmp); if (fips_enabled) { + unsigned long flags; + spin_lock_irqsave(&r->lock, flags); if (!memcmp(tmp, r->last_data, EXTRACT_SIZE)) panic("Hardware RNG duplicated output!\n"); @@ -898,6 +1019,7 @@ static ssize_t extract_entropy_user(stru ssize_t ret = 0, i; __u8 tmp[EXTRACT_SIZE]; + trace_extract_entropy_user(r->name, nbytes, r->entropy_count, _RET_IP_); xfer_secondary_pool(r, nbytes); nbytes = account(r, nbytes, 0, 0); @@ -931,17 +1053,35 @@ static ssize_t extract_entropy_user(stru /* * This function is the exported kernel interface. It returns some - * number of good random numbers, suitable for seeding TCP sequence - * numbers, etc. + * number of good random numbers, suitable for key generation, seeding + * TCP sequence numbers, etc. It does not use the hw random number + * generator, if available; use get_random_bytes_arch() for that. */ void get_random_bytes(void *buf, int nbytes) { + extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0); +} +EXPORT_SYMBOL(get_random_bytes); + +/* + * This function will use the architecture-specific hardware random + * number generator if it is available. The arch-specific hw RNG will + * almost certainly be faster than what we can do in software, but it + * is impossible to verify that it is implemented securely (as + * opposed, to, say, the AES encryption of a sequence number using a + * key known by the NSA). So it's useful if we need the speed, but + * only if we're willing to trust the hardware manufacturer not to + * have put in a back door. + */ +void get_random_bytes_arch(void *buf, int nbytes) +{ char *p = buf; + trace_get_random_bytes(nbytes, _RET_IP_); while (nbytes) { unsigned long v; int chunk = min(nbytes, (int)sizeof(unsigned long)); - + if (!arch_get_random_long(&v)) break; @@ -950,9 +1090,11 @@ void get_random_bytes(void *buf, int nby nbytes -= chunk; } - extract_entropy(&nonblocking_pool, p, nbytes, 0, 0); + if (nbytes) + extract_entropy(&nonblocking_pool, p, nbytes, 0, 0); } -EXPORT_SYMBOL(get_random_bytes); +EXPORT_SYMBOL(get_random_bytes_arch); + /* * init_std_data - initialize pool with system data @@ -966,21 +1108,18 @@ EXPORT_SYMBOL(get_random_bytes); static void init_std_data(struct entropy_store *r) { int i; - ktime_t now; - unsigned long flags; + ktime_t now = ktime_get_real(); + unsigned long rv; - spin_lock_irqsave(&r->lock, flags); r->entropy_count = 0; - spin_unlock_irqrestore(&r->lock, flags); - - now = ktime_get_real(); - mix_pool_bytes(r, &now, sizeof(now)); - for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof flags) { - if (!arch_get_random_long(&flags)) + r->entropy_total = 0; + mix_pool_bytes(r, &now, sizeof(now), NULL); + for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof(rv)) { + if (!arch_get_random_long(&rv)) break; - mix_pool_bytes(r, &flags, sizeof(flags)); + mix_pool_bytes(r, &rv, sizeof(rv), NULL); } - mix_pool_bytes(r, utsname(), sizeof(*(utsname()))); + mix_pool_bytes(r, utsname(), sizeof(*(utsname())), NULL); } static int rand_initialize(void) @@ -1117,7 +1256,7 @@ write_pool(struct entropy_store *r, cons count -= bytes; p += bytes; - mix_pool_bytes(r, buf, bytes); + mix_pool_bytes(r, buf, bytes, NULL); cond_resched(); } @@ -1274,6 +1413,7 @@ static int proc_do_uuid(ctl_table *table } static int sysctl_poolsize = INPUT_POOL_WORDS * 32; +extern ctl_table random_table[]; ctl_table random_table[] = { { .procname = "poolsize", @@ -1339,7 +1479,7 @@ late_initcall(random_int_secret_init); * value is not cryptographically secure but for several uses the cost of * depleting entropy is too high */ -DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash); +static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash); unsigned int get_random_int(void) { __u32 *hash; --- a/drivers/mfd/ab3100-core.c +++ b/drivers/mfd/ab3100-core.c @@ -409,8 +409,6 @@ static irqreturn_t ab3100_irq_handler(in u32 fatevent; int err; - add_interrupt_randomness(irq); - err = ab3100_get_register_page_interruptible(ab3100, AB3100_EVENTA1, event_regs, 3); if (err) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -1896,6 +1897,14 @@ int usb_new_device(struct usb_device *ud /* Tell the world! */ announce_device(udev); + if (udev->serial) + add_device_randomness(udev->serial, strlen(udev->serial)); + if (udev->product) + add_device_randomness(udev->product, strlen(udev->product)); + if (udev->manufacturer) + add_device_randomness(udev->manufacturer, + strlen(udev->manufacturer)); + device_enable_async_suspend(&udev->dev); /* Register the device. The device driver is responsible * for configuring the device and invoking the add-device --- a/include/linux/random.h +++ b/include/linux/random.h @@ -50,11 +50,13 @@ struct rnd_state { extern void rand_initialize_irq(int irq); +extern void add_device_randomness(const void *, unsigned int); extern void add_input_randomness(unsigned int type, unsigned int code, unsigned int value); -extern void add_interrupt_randomness(int irq); +extern void add_interrupt_randomness(int irq, int irq_flags); extern void get_random_bytes(void *buf, int nbytes); +extern void get_random_bytes_arch(void *buf, int nbytes); void generate_random_uuid(unsigned char uuid_out[16]); #ifndef MODULE --- /dev/null +++ b/include/trace/events/random.h @@ -0,0 +1,134 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM random + +#if !defined(_TRACE_RANDOM_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_RANDOM_H + +#include +#include + +DECLARE_EVENT_CLASS(random__mix_pool_bytes, + TP_PROTO(const char *pool_name, int bytes, unsigned long IP), + + TP_ARGS(pool_name, bytes, IP), + + TP_STRUCT__entry( + __field( const char *, pool_name ) + __field( int, bytes ) + __field(unsigned long, IP ) + ), + + TP_fast_assign( + __entry->pool_name = pool_name; + __entry->bytes = bytes; + __entry->IP = IP; + ), + + TP_printk("%s pool: bytes %d caller %pF", + __entry->pool_name, __entry->bytes, (void *)__entry->IP) +); + +DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes, + TP_PROTO(const char *pool_name, int bytes, unsigned long IP), + + TP_ARGS(pool_name, bytes, IP) +); + +DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes_nolock, + TP_PROTO(const char *pool_name, int bytes, unsigned long IP), + + TP_ARGS(pool_name, bytes, IP) +); + +TRACE_EVENT(credit_entropy_bits, + TP_PROTO(const char *pool_name, int bits, int entropy_count, + int entropy_total, unsigned long IP), + + TP_ARGS(pool_name, bits, entropy_count, entropy_total, IP), + + TP_STRUCT__entry( + __field( const char *, pool_name ) + __field( int, bits ) + __field( int, entropy_count ) + __field( int, entropy_total ) + __field(unsigned long, IP ) + ), + + TP_fast_assign( + __entry->pool_name = pool_name; + __entry->bits = bits; + __entry->entropy_count = entropy_count; + __entry->entropy_total = entropy_total; + __entry->IP = IP; + ), + + TP_printk("%s pool: bits %d entropy_count %d entropy_total %d " + "caller %pF", __entry->pool_name, __entry->bits, + __entry->entropy_count, __entry->entropy_total, + (void *)__entry->IP) +); + +TRACE_EVENT(get_random_bytes, + TP_PROTO(int nbytes, unsigned long IP), + + TP_ARGS(nbytes, IP), + + TP_STRUCT__entry( + __field( int, nbytes ) + __field(unsigned long, IP ) + ), + + TP_fast_assign( + __entry->nbytes = nbytes; + __entry->IP = IP; + ), + + TP_printk("nbytes %d caller %pF", __entry->nbytes, (void *)__entry->IP) +); + +DECLARE_EVENT_CLASS(random__extract_entropy, + TP_PROTO(const char *pool_name, int nbytes, int entropy_count, + unsigned long IP), + + TP_ARGS(pool_name, nbytes, entropy_count, IP), + + TP_STRUCT__entry( + __field( const char *, pool_name ) + __field( int, nbytes ) + __field( int, entropy_count ) + __field(unsigned long, IP ) + ), + + TP_fast_assign( + __entry->pool_name = pool_name; + __entry->nbytes = nbytes; + __entry->entropy_count = entropy_count; + __entry->IP = IP; + ), + + TP_printk("%s pool: nbytes %d entropy_count %d caller %pF", + __entry->pool_name, __entry->nbytes, __entry->entropy_count, + (void *)__entry->IP) +); + + +DEFINE_EVENT(random__extract_entropy, extract_entropy, + TP_PROTO(const char *pool_name, int nbytes, int entropy_count, + unsigned long IP), + + TP_ARGS(pool_name, nbytes, entropy_count, IP) +); + +DEFINE_EVENT(random__extract_entropy, extract_entropy_user, + TP_PROTO(const char *pool_name, int nbytes, int entropy_count, + unsigned long IP), + + TP_ARGS(pool_name, nbytes, entropy_count, IP) +); + + + +#endif /* _TRACE_RANDOM_H */ + +/* This part must be outside protection */ +#include --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -117,7 +117,7 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) { irqreturn_t retval = IRQ_NONE; - unsigned int random = 0, irq = desc->irq_data.irq; + unsigned int flags = 0, irq = desc->irq_data.irq; do { irqreturn_t res; @@ -145,7 +145,7 @@ handle_irq_event_percpu(struct irq_desc /* Fall through to add to randomness */ case IRQ_HANDLED: - random |= action->flags; + flags |= action->flags; break; default: @@ -156,8 +156,7 @@ handle_irq_event_percpu(struct irq_desc action = action->next; } while (action); - if (random & IRQF_SAMPLE_RANDOM) - add_interrupt_randomness(irq); + add_interrupt_randomness(irq, flags); if (!noirqdebug) note_interrupt(irq, desc, retval); --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1176,6 +1176,7 @@ static int __dev_open(struct net_device net_dmaengine_get(); dev_set_rx_mode(dev); dev_activate(dev); + add_device_randomness(dev->dev_addr, dev->addr_len); } return ret; @@ -4823,6 +4824,7 @@ int dev_set_mac_address(struct net_devic err = ops->ndo_set_mac_address(dev, sa); if (!err) call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); + add_device_randomness(dev->dev_addr, dev->addr_len); return err; } EXPORT_SYMBOL(dev_set_mac_address); @@ -5602,6 +5604,7 @@ int register_netdevice(struct net_device dev_init_scheduler(dev); dev_hold(dev); list_netdevice(dev); + add_device_randomness(dev->dev_addr, dev->addr_len); /* Notify protocols, that a new device appeared. */ ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1371,6 +1371,7 @@ static int do_setlink(struct net_device goto errout; send_addr_notify = 1; modified = 1; + add_device_randomness(dev->dev_addr, dev->addr_len); } if (tb[IFLA_MTU]) {