[PATCH v3 2/3] treewide: use get_random_u32_{above,below}() instead of manual loop
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: 2022-11-17 20:29:51
Also in:
linux-arm-kernel, linux-block, linux-crypto, linux-fsdevel, linux-media, linux-mips, linux-mmc, linux-patches, lkml, loongarch, netdev
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), library code, networking [general], networking [ipv4/ipv6], the rest, vm sockets (af_vsock) · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Andrew Morton, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds, Stefano Garzarella
These cases were done with this Coccinelle:
@@
expression E;
identifier I;
@@
- do {
... when != I
- I = get_random_u32();
... when != I
- } while (I > E);
+ I = get_random_u32_below(E + 1);
@@
expression E;
identifier I;
@@
- do {
... when != I
- I = get_random_u32();
... when != I
- } while (I >= E);
+ I = get_random_u32_below(E);
@@
expression E;
identifier I;
@@
- do {
... when != I
- I = get_random_u32();
... when != I
- } while (I < E);
+ I = get_random_u32_above(E - 1);
@@
expression E;
identifier I;
@@
- do {
... when != I
- I = get_random_u32();
... when != I
- } while (I <= E);
+ I = get_random_u32_above(E);
@@
identifier I;
@@
- do {
... when != I
- I = get_random_u32();
... when != I
- } while (!I);
+ I = get_random_u32_above(0);
@@
identifier I;
@@
- do {
... when != I
- I = get_random_u32();
... when != I
- } while (I == 0);
+ I = get_random_u32_above(0);
@@
expression E;
@@
- E + 1 + get_random_u32_below(U32_MAX - E)
+ get_random_u32_above(E)
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
fs/ext4/mmp.c | 8 +-------
lib/test_fprobe.c | 5 +----
lib/test_kprobes.c | 5 +----
net/ipv6/output_core.c | 8 +-------
net/vmw_vsock/af_vsock.c | 3 +--
5 files changed, 5 insertions(+), 24 deletions(-)
diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c
index 588cb09c5291..4681fff6665f 100644
--- a/fs/ext4/mmp.c
+++ b/fs/ext4/mmp.c@@ -262,13 +262,7 @@ void ext4_stop_mmpd(struct ext4_sb_info *sbi) */ static unsigned int mmp_new_seq(void) { - u32 new_seq; - - do { - new_seq = get_random_u32(); - } while (new_seq > EXT4_MMP_SEQ_MAX); - - return new_seq; + return get_random_u32_below(EXT4_MMP_SEQ_MAX + 1); } /*
diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c
index e0381b3ec410..1fb56cf5e5ce 100644
--- a/lib/test_fprobe.c
+++ b/lib/test_fprobe.c@@ -144,10 +144,7 @@ static unsigned long get_ftrace_location(void *func) static int fprobe_test_init(struct kunit *test) { - do { - rand1 = get_random_u32(); - } while (rand1 <= div_factor); - + rand1 = get_random_u32_above(div_factor); target = fprobe_selftest_target; target2 = fprobe_selftest_target2; target_ip = get_ftrace_location(target);
diff --git a/lib/test_kprobes.c b/lib/test_kprobes.c
index eeb1d728d974..1c95e5719802 100644
--- a/lib/test_kprobes.c
+++ b/lib/test_kprobes.c@@ -339,10 +339,7 @@ static int kprobes_test_init(struct kunit *test) stacktrace_target = kprobe_stacktrace_target; internal_target = kprobe_stacktrace_internal_target; stacktrace_driver = kprobe_stacktrace_driver; - - do { - rand1 = get_random_u32(); - } while (rand1 <= div_factor); + rand1 = get_random_u32_above(div_factor); return 0; }
diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c
index 2685c3f15e9d..b5205311f372 100644
--- a/net/ipv6/output_core.c
+++ b/net/ipv6/output_core.c@@ -15,13 +15,7 @@ static u32 __ipv6_select_ident(struct net *net, const struct in6_addr *dst, const struct in6_addr *src) { - u32 id; - - do { - id = get_random_u32(); - } while (!id); - - return id; + return get_random_u32_above(0); } /* This function exists only for tap drivers that must support broken
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index ff38c5a4d174..d593d5b6d4b1 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c@@ -626,8 +626,7 @@ static int __vsock_bind_connectible(struct vsock_sock *vsk, struct sockaddr_vm new_addr; if (!port) - port = LAST_RESERVED_PORT + 1 + - get_random_u32_below(U32_MAX - LAST_RESERVED_PORT); + port = get_random_u32_above(LAST_RESERVED_PORT); vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
--
2.38.1