Re: [PATCH v3 2/3] treewide: use get_random_u32_{above,below}() instead of manual loop
From: Kees Cook <hidden>
Date: 2022-11-17 22:00:08
Also in:
linux-arm-kernel, linux-block, linux-crypto, linux-fsdevel, linux-media, linux-mips, linux-mmc, linux-patches, lkml, loongarch, netdev
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 <redacted> -- Kees Cook