From f17b62cb59c21195aaa699a331076a55655a6652 Mon Sep 17 00:00:00 2001 From: Jeremy Cline Date: Jun 29 2018 13:48:43 +0000 Subject: Bring back the revert for rhbz 1572944 --- diff --git a/Revert-the-random-series-for-4.16.4.patch b/Revert-the-random-series-for-4.16.4.patch new file mode 100644 index 0000000..f410fd3 --- /dev/null +++ b/Revert-the-random-series-for-4.16.4.patch @@ -0,0 +1,160 @@ +From 5744a0927df22f46e4b7f134b3dfb405fdfcf6ce Mon Sep 17 00:00:00 2001 +From: Jeremy Cline +Date: Wed, 2 May 2018 15:16:29 -0400 +Subject: [PATCH 1/2] Revert "random: use a different mixing algorithm for + add_device_randomness()" + +This reverts commit 89b59f050347d376c2ace8b1ceb908a218cfdc2e. + +Signed-off-by: Jeremy Cline +--- + drivers/char/random.c | 55 ++++--------------------------------------- + 1 file changed, 4 insertions(+), 51 deletions(-) + +diff --git a/drivers/char/random.c b/drivers/char/random.c +index 8f4e11842c60..aa5b04af86c6 100644 +--- a/drivers/char/random.c ++++ b/drivers/char/random.c +@@ -831,10 +831,6 @@ static void numa_crng_init(void) + static void numa_crng_init(void) {} + #endif + +-/* +- * crng_fast_load() can be called by code in the interrupt service +- * path. So we can't afford to dilly-dally. +- */ + static int crng_fast_load(const char *cp, size_t len) + { + unsigned long flags; +@@ -861,51 +857,6 @@ static int crng_fast_load(const char *cp, size_t len) + return 1; + } + +-/* +- * crng_slow_load() is called by add_device_randomness, which has two +- * attributes. (1) We can't trust the buffer passed to it is +- * guaranteed to be unpredictable (so it might not have any entropy at +- * all), and (2) it doesn't have the performance constraints of +- * crng_fast_load(). +- * +- * So we do something more comprehensive which is guaranteed to touch +- * all of the primary_crng's state, and which uses a LFSR with a +- * period of 255 as part of the mixing algorithm. Finally, we do +- * *not* advance crng_init_cnt since buffer we may get may be something +- * like a fixed DMI table (for example), which might very well be +- * unique to the machine, but is otherwise unvarying. +- */ +-static int crng_slow_load(const char *cp, size_t len) +-{ +- unsigned long flags; +- static unsigned char lfsr = 1; +- unsigned char tmp; +- unsigned i, max = CHACHA20_KEY_SIZE; +- const char * src_buf = cp; +- char * dest_buf = (char *) &primary_crng.state[4]; +- +- if (!spin_trylock_irqsave(&primary_crng.lock, flags)) +- return 0; +- if (crng_init != 0) { +- spin_unlock_irqrestore(&primary_crng.lock, flags); +- return 0; +- } +- if (len > max) +- max = len; +- +- for (i = 0; i < max ; i++) { +- tmp = lfsr; +- lfsr >>= 1; +- if (tmp & 1) +- lfsr ^= 0xE1; +- tmp = dest_buf[i % CHACHA20_KEY_SIZE]; +- dest_buf[i % CHACHA20_KEY_SIZE] ^= src_buf[i % len] ^ lfsr; +- lfsr += (tmp << 3) | (tmp >> 5); +- } +- spin_unlock_irqrestore(&primary_crng.lock, flags); +- return 1; +-} +- + static void crng_reseed(struct crng_state *crng, struct entropy_store *r) + { + unsigned long flags; +@@ -1089,8 +1040,10 @@ void add_device_randomness(const void *buf, unsigned int size) + unsigned long time = random_get_entropy() ^ jiffies; + unsigned long flags; + +- if (!crng_ready() && size) +- crng_slow_load(buf, size); ++ if (!crng_ready()) { ++ crng_fast_load(buf, size); ++ return; ++ } + + trace_add_device_randomness(size, _RET_IP_); + spin_lock_irqsave(&input_pool.lock, flags); +-- +2.17.0 + +From e1b1b5b62740b0e6ea8258a4eb81b2a336538fed Mon Sep 17 00:00:00 2001 +From: Jeremy Cline +Date: Wed, 2 May 2018 15:18:03 -0400 +Subject: [PATCH 2/2] Revert "random: fix crng_ready() test" + +This reverts commit cd8d7a5778a4abf76ee8fe8f1bfcf78976029f8d. + +Signed-off-by: Jeremy Cline +--- + drivers/char/random.c | 10 +++++----- + 1 file changed, 5 insertions(+), 5 deletions(-) + +diff --git a/drivers/char/random.c b/drivers/char/random.c +index aa5b04af86c6..ef05cc685b74 100644 +--- a/drivers/char/random.c ++++ b/drivers/char/random.c +@@ -428,7 +428,7 @@ struct crng_state primary_crng = { + * its value (from 0->1->2). + */ + static int crng_init = 0; +-#define crng_ready() (likely(crng_init > 1)) ++#define crng_ready() (likely(crng_init > 0)) + static int crng_init_cnt = 0; + static unsigned long crng_global_init_time = 0; + #define CRNG_INIT_CNT_THRESH (2*CHACHA20_KEY_SIZE) +@@ -838,7 +838,7 @@ static int crng_fast_load(const char *cp, size_t len) + + if (!spin_trylock_irqsave(&primary_crng.lock, flags)) + return 0; +- if (crng_init != 0) { ++ if (crng_ready()) { + spin_unlock_irqrestore(&primary_crng.lock, flags); + return 0; + } +@@ -913,7 +913,7 @@ static void _extract_crng(struct crng_state *crng, + { + unsigned long v, flags; + +- if (crng_ready() && ++ if (crng_init > 1 && + (time_after(crng_global_init_time, crng->init_time) || + time_after(jiffies, crng->init_time + CRNG_RESEED_INTERVAL))) + crng_reseed(crng, crng == &primary_crng ? &input_pool : NULL); +@@ -1200,7 +1200,7 @@ void add_interrupt_randomness(int irq, int irq_flags) + fast_mix(fast_pool); + add_interrupt_bench(cycles); + +- if (unlikely(crng_init == 0)) { ++ if (!crng_ready()) { + if ((fast_pool->count >= 64) && + crng_fast_load((char *) fast_pool->pool, + sizeof(fast_pool->pool))) { +@@ -2269,7 +2269,7 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, + { + struct entropy_store *poolp = &input_pool; + +- if (unlikely(crng_init == 0)) { ++ if (!crng_ready()) { + crng_fast_load(buffer, count); + return; + } +-- +2.17.0 + diff --git a/kernel.spec b/kernel.spec index 8ea809e..57026a7 100644 --- a/kernel.spec +++ b/kernel.spec @@ -655,6 +655,9 @@ Patch515: 0001-signal-Stop-special-casing-TRAP_FIXME-and-FPE_FIXME-.patch # CVE-2018-12714 rhbz 1595835 1595837 Patch516: CVE-2018-12714.patch +# rhbz 1572944 +Patch517: Revert-the-random-series-for-4.16.4.patch + # END OF PATCH DEFINITIONS %endif @@ -1904,6 +1907,9 @@ fi # # %changelog +* Fri Jun 29 2018 Jeremy Cline +- Revert the CRNG init patches (rhbz 1572944) + * Thu Jun 28 2018 Jeremy Cline - Fix CVE-2018-12714 (rhbz 1595835 1595837)