Re: Linux 5.4.57

From: Greg Kroah-Hartman
Date: Fri Aug 07 2020 - 04:15:34 EST

diff --git a/Makefile b/Makefile
index c33fb4eebd4d..dd753ef637fd 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
VERSION = 5
PATCHLEVEL = 4
-SUBLEVEL = 56
+SUBLEVEL = 57
EXTRAVERSION =
NAME = Kleptomaniac Octopus

diff --git a/arch/arm/include/asm/percpu.h b/arch/arm/include/asm/percpu.h
index f44f448537f2..1a3eedbac4a2 100644
--- a/arch/arm/include/asm/percpu.h
+++ b/arch/arm/include/asm/percpu.h
@@ -5,6 +5,8 @@
#ifndef _ASM_ARM_PERCPU_H_
#define _ASM_ARM_PERCPU_H_

+#include <asm/thread_info.h>
+
/*
* Same as asm-generic/percpu.h, except that we store the per cpu offset
* in the TPIDRPRW. TPIDRPRW only exists on V6K and V7
diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h
index 7a24bad1a58b..076a4157a74f 100644
--- a/arch/arm64/include/asm/pointer_auth.h
+++ b/arch/arm64/include/asm/pointer_auth.h
@@ -3,7 +3,6 @@
#define __ASM_POINTER_AUTH_H

#include <linux/bitops.h>
-#include <linux/random.h>

#include <asm/cpufeature.h>
#include <asm/memory.h>
@@ -30,6 +29,13 @@ struct ptrauth_keys {
struct ptrauth_key apga;
};

+/*
+ * Only include random.h once ptrauth_keys_* structures are defined
+ * to avoid yet another circular include hell (random.h * ends up
+ * including asm/smp.h, which requires ptrauth_keys_kernel).
+ */
+#include <linux/random.h>
+
static inline void ptrauth_keys_init(struct ptrauth_keys *keys)
{
if (system_supports_address_auth()) {
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 8ff28c14af7e..e877c20e0ee0 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1330,6 +1330,7 @@ void add_interrupt_randomness(int irq, int irq_flags)

fast_mix(fast_pool);
add_interrupt_bench(cycles);
+ this_cpu_add(net_rand_state.s1, fast_pool->pool[cycles & 3]);

if (unlikely(crng_init == 0)) {
if ((fast_pool->count >= 64) &&
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 7e0c77de551b..a284d99a1ee5 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3836,6 +3836,11 @@ static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter)
struct inode *inode = mapping->host;
size_t count = iov_iter_count(iter);
ssize_t ret;
+ loff_t offset = iocb->ki_pos;
+ loff_t size = i_size_read(inode);
+
+ if (offset >= size)
+ return 0;

/*
* Shared inode_lock is enough for us - it protects against concurrent
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 3bf3835d0e86..7aa0d8b5aaf0 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -956,11 +956,14 @@ static inline void bpf_map_offload_map_free(struct bpf_map *map)
#endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */

#if defined(CONFIG_BPF_STREAM_PARSER)
-int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, u32 which);
+int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
+ struct bpf_prog *old, u32 which);
int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog);
+int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype);
#else
static inline int sock_map_prog_update(struct bpf_map *map,
- struct bpf_prog *prog, u32 which)
+ struct bpf_prog *prog,
+ struct bpf_prog *old, u32 which)
{
return -EOPNOTSUPP;
}
@@ -970,6 +973,12 @@ static inline int sock_map_get_from_fd(const union bpf_attr *attr,
{
return -EINVAL;
}
+
+static inline int sock_map_prog_detach(const union bpf_attr *attr,
+ enum bpf_prog_type ptype)
+{
+ return -EOPNOTSUPP;
+}
#endif

#if defined(CONFIG_XDP_SOCKETS)
diff --git a/include/linux/prandom.h b/include/linux/prandom.h
new file mode 100644
index 000000000000..aa16e6468f91
--- /dev/null
+++ b/include/linux/prandom.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * include/linux/prandom.h
+ *
+ * Include file for the fast pseudo-random 32-bit
+ * generation.
+ */
+#ifndef _LINUX_PRANDOM_H
+#define _LINUX_PRANDOM_H
+
+#include <linux/types.h>
+#include <linux/percpu.h>
+
+u32 prandom_u32(void);
+void prandom_bytes(void *buf, size_t nbytes);
+void prandom_seed(u32 seed);
+void prandom_reseed_late(void);
+
+struct rnd_state {
+ __u32 s1, s2, s3, s4;
+};
+
+DECLARE_PER_CPU(struct rnd_state, net_rand_state);
+
+u32 prandom_u32_state(struct rnd_state *state);
+void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes);
+void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state);
+
+#define prandom_init_once(pcpu_state) \
+ DO_ONCE(prandom_seed_full_state, (pcpu_state))
+
+/**
+ * prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro)
+ * @ep_ro: right open interval endpoint
+ *
+ * Returns a pseudo-random number that is in interval [0, ep_ro). Note
+ * that the result depends on PRNG being well distributed in [0, ~0U]
+ * u32 space. Here we use maximally equidistributed combined Tausworthe
+ * generator, that is, prandom_u32(). This is useful when requesting a
+ * random index of an array containing ep_ro elements, for example.
+ *
+ * Returns: pseudo-random number in interval [0, ep_ro)
+ */
+static inline u32 prandom_u32_max(u32 ep_ro)
+{
+ return (u32)(((u64) prandom_u32() * ep_ro) >> 32);
+}
+
+/*
+ * Handle minimum values for seeds
+ */
+static inline u32 __seed(u32 x, u32 m)
+{
+ return (x < m) ? x + m : x;
+}
+
+/**
+ * prandom_seed_state - set seed for prandom_u32_state().
+ * @state: pointer to state structure to receive the seed.
+ * @seed: arbitrary 64-bit value to use as a seed.
+ */
+static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
+{
+ u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
+
+ state->s1 = __seed(i, 2U);
+ state->s2 = __seed(i, 8U);
+ state->s3 = __seed(i, 16U);
+ state->s4 = __seed(i, 128U);
+}
+
+/* Pseudo random number generator from numerical recipes. */
+static inline u32 next_pseudo_random32(u32 seed)
+{
+ return seed * 1664525 + 1013904223;
+}
+
+#endif
diff --git a/include/linux/random.h b/include/linux/random.h
index f189c927fdea..5b3ec7d2791f 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -108,61 +108,12 @@ declare_get_random_var_wait(long)

unsigned long randomize_page(unsigned long start, unsigned long range);

-u32 prandom_u32(void);
-void prandom_bytes(void *buf, size_t nbytes);
-void prandom_seed(u32 seed);
-void prandom_reseed_late(void);
-
-struct rnd_state {
- __u32 s1, s2, s3, s4;
-};
-
-u32 prandom_u32_state(struct rnd_state *state);
-void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes);
-void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state);
-
-#define prandom_init_once(pcpu_state) \
- DO_ONCE(prandom_seed_full_state, (pcpu_state))
-
-/**
- * prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro)
- * @ep_ro: right open interval endpoint
- *
- * Returns a pseudo-random number that is in interval [0, ep_ro). Note
- * that the result depends on PRNG being well distributed in [0, ~0U]
- * u32 space. Here we use maximally equidistributed combined Tausworthe
- * generator, that is, prandom_u32(). This is useful when requesting a
- * random index of an array containing ep_ro elements, for example.
- *
- * Returns: pseudo-random number in interval [0, ep_ro)
- */
-static inline u32 prandom_u32_max(u32 ep_ro)
-{
- return (u32)(((u64) prandom_u32() * ep_ro) >> 32);
-}
-
/*
- * Handle minimum values for seeds
+ * This is designed to be standalone for just prandom
+ * users, but for now we include it from <linux/random.h>
+ * for legacy reasons.
*/
-static inline u32 __seed(u32 x, u32 m)
-{
- return (x < m) ? x + m : x;
-}
-
-/**
- * prandom_seed_state - set seed for prandom_u32_state().
- * @state: pointer to state structure to receive the seed.
- * @seed: arbitrary 64-bit value to use as a seed.
- */
-static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
-{
- u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
-
- state->s1 = __seed(i, 2U);
- state->s2 = __seed(i, 8U);
- state->s3 = __seed(i, 16U);
- state->s4 = __seed(i, 128U);
-}
+#include <linux/prandom.h>

#ifdef CONFIG_ARCH_RANDOM
# include <asm/archrandom.h>
@@ -193,10 +144,4 @@ static inline bool arch_has_random_seed(void)
}
#endif

-/* Pseudo random number generator from numerical recipes. */
-static inline u32 next_pseudo_random32(u32 seed)
-{
- return seed * 1664525 + 1013904223;
-}
-
#endif /* _LINUX_RANDOM_H */
diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 4bdb5e4bbd6a..20f3550b0b11 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -450,6 +450,19 @@ static inline void psock_set_prog(struct bpf_prog **pprog,
bpf_prog_put(prog);
}

+static inline int psock_replace_prog(struct bpf_prog **pprog,
+ struct bpf_prog *prog,
+ struct bpf_prog *old)
+{
+ if (cmpxchg(pprog, old, prog) != old)
+ return -ENOENT;
+
+ if (old)
+ bpf_prog_put(old);
+
+ return 0;
+}
+
static inline void psock_progs_drop(struct sk_psock_progs *progs)
{
psock_set_prog(&progs->msg_parser, NULL);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 8bc904f9badb..bf03d04a9e2f 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2029,10 +2029,10 @@ static int bpf_prog_detach(const union bpf_attr *attr)
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
break;
case BPF_SK_MSG_VERDICT:
- return sock_map_get_from_fd(attr, NULL);
+ return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_MSG);
case BPF_SK_SKB_STREAM_PARSER:
case BPF_SK_SKB_STREAM_VERDICT:
- return sock_map_get_from_fd(attr, NULL);
+ return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_SKB);
case BPF_LIRC_MODE2:
return lirc_prog_detach(attr);
case BPF_FLOW_DISSECTOR:
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 1e9b81a930c0..a3ae244b1bcd 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -43,6 +43,7 @@
#include <linux/sched/debug.h>
#include <linux/slab.h>
#include <linux/compat.h>
+#include <linux/random.h>

#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -1742,6 +1743,13 @@ void update_process_times(int user_tick)
scheduler_tick();
if (IS_ENABLED(CONFIG_POSIX_TIMERS))
run_posix_cpu_timers();
+
+ /* The current CPU might make use of net randoms without receiving IRQs
+ * to renew them often enough. Let's update the net_rand_state from a
+ * non-constant value that's not affine to the number of calls to make
+ * sure it's updated when there's some activity (we don't care in idle).
+ */
+ this_cpu_add(net_rand_state.s1, rol32(jiffies, 24) + user_tick);
}

/**
diff --git a/lib/random32.c b/lib/random32.c
index 763b920a6206..3d749abb9e80 100644
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -48,7 +48,7 @@ static inline void prandom_state_selftest(void)
}
#endif

-static DEFINE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy;
+DEFINE_PER_CPU(struct rnd_state, net_rand_state);

/**
* prandom_u32_state - seeded pseudo-random number generator.
diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 6bbc118bf00e..df52061f99f7 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -71,7 +71,42 @@ int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog)
map = __bpf_map_get(f);
if (IS_ERR(map))
return PTR_ERR(map);
- ret = sock_map_prog_update(map, prog, attr->attach_type);
+ ret = sock_map_prog_update(map, prog, NULL, attr->attach_type);
+ fdput(f);
+ return ret;
+}
+
+int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype)
+{
+ u32 ufd = attr->target_fd;
+ struct bpf_prog *prog;
+ struct bpf_map *map;
+ struct fd f;
+ int ret;
+
+ if (attr->attach_flags)
+ return -EINVAL;
+
+ f = fdget(ufd);
+ map = __bpf_map_get(f);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ prog = bpf_prog_get(attr->attach_bpf_fd);
+ if (IS_ERR(prog)) {
+ ret = PTR_ERR(prog);
+ goto put_map;
+ }
+
+ if (prog->type != ptype) {
+ ret = -EINVAL;
+ goto put_prog;
+ }
+
+ ret = sock_map_prog_update(map, NULL, prog, attr->attach_type);
+put_prog:
+ bpf_prog_put(prog);
+put_map:
fdput(f);
return ret;
}
@@ -1015,27 +1050,32 @@ static struct sk_psock_progs *sock_map_progs(struct bpf_map *map)
}

int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
- u32 which)
+ struct bpf_prog *old, u32 which)
{
struct sk_psock_progs *progs = sock_map_progs(map);
+ struct bpf_prog **pprog;

if (!progs)
return -EOPNOTSUPP;

switch (which) {
case BPF_SK_MSG_VERDICT:
- psock_set_prog(&progs->msg_parser, prog);
+ pprog = &progs->msg_parser;
break;
case BPF_SK_SKB_STREAM_PARSER:
- psock_set_prog(&progs->skb_parser, prog);
+ pprog = &progs->skb_parser;
break;
case BPF_SK_SKB_STREAM_VERDICT:
- psock_set_prog(&progs->skb_verdict, prog);
+ pprog = &progs->skb_verdict;
break;
default:
return -EOPNOTSUPP;
}

+ if (old)
+ return psock_replace_prog(pprog, prog, old);
+
+ psock_set_prog(pprog, prog);
return 0;
}

diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index e1f1becda529..c812f0178b64 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -793,19 +793,19 @@ static void test_sockmap(unsigned int tasks, void *data)
}

err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_PARSER);
- if (err) {
+ if (!err) {
printf("Failed empty parser prog detach\n");
goto out_sockmap;
}

err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_VERDICT);
- if (err) {
+ if (!err) {
printf("Failed empty verdict prog detach\n");
goto out_sockmap;
}

err = bpf_prog_detach(fd, BPF_SK_MSG_VERDICT);
- if (err) {
+ if (!err) {
printf("Failed empty msg verdict prog detach\n");
goto out_sockmap;
}
@@ -1094,19 +1094,19 @@ static void test_sockmap(unsigned int tasks, void *data)
assert(status == 0);
}

- err = bpf_prog_detach(map_fd_rx, __MAX_BPF_ATTACH_TYPE);
+ err = bpf_prog_detach2(parse_prog, map_fd_rx, __MAX_BPF_ATTACH_TYPE);
if (!err) {
printf("Detached an invalid prog type.\n");
goto out_sockmap;
}

- err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_PARSER);
+ err = bpf_prog_detach2(parse_prog, map_fd_rx, BPF_SK_SKB_STREAM_PARSER);
if (err) {
printf("Failed parser prog detach\n");
goto out_sockmap;
}

- err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_VERDICT);
+ err = bpf_prog_detach2(verdict_prog, map_fd_rx, BPF_SK_SKB_STREAM_VERDICT);
if (err) {
printf("Failed parser prog detach\n");
goto out_sockmap;