| Message ID | 20221117202906.2312482-3-Jason@zx2c4.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | None | expand |
On Thu, Nov 17, 2022 at 09:29:05PM +0100, Jason A. Donenfeld wrote: > 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> Reviewed-by: Kees Cook <keescook@chromium.org>
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);
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(-)