Jason A. Donenfeld 7e3cf0843f treewide: use get_random_{u8,u16}() when possible, part 1 ... Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value, simply use the get_random_{u8,u16}() functions, which are faster than wasting the additional bytes from a 32-bit value. This was done mechanically with this coccinelle script: @@ expression E; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u16; typedef __be16; typedef __le16; typedef u8; @@ ( - (get_random_u32() & 0xffff) + get_random_u16() | - (get_random_u32() & 0xff) + get_random_u8() | - (get_random_u32() % 65536) + get_random_u16() | - (get_random_u32() % 256) + get_random_u8() | - (get_random_u32() >> 16) + get_random_u16() | - (get_random_u32() >> 24) + get_random_u8() | - (u16)get_random_u32() + get_random_u16() | - (u8)get_random_u32() + get_random_u8() | - (__be16)get_random_u32() + (__be16)get_random_u16() | - (__le16)get_random_u32() + (__le16)get_random_u16() | - prandom_u32_max(65536) + get_random_u16() | - prandom_u32_max(256) + get_random_u8() | - E->inet_id = get_random_u32() + E->inet_id = get_random_u16() ) @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u16; identifier v; @@ - u16 v = get_random_u32(); + u16 v = get_random_u16(); @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u8; identifier v; @@ - u8 v = get_random_u32(); + u8 v = get_random_u8(); @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u16; u16 v; @@ - v = get_random_u32(); + v = get_random_u16(); @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u8; u8 v; @@ - v = get_random_u32(); + v = get_random_u8(); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Examine limits @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value < 256: coccinelle.RESULT = cocci.make_ident("get_random_u8") elif value < 65536: coccinelle.RESULT = cocci.make_ident("get_random_u16") else: print("Skipping large mask of %s" % (literal)) cocci.include_match(False) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; identifier add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + (RESULT() & LITERAL) Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>		2022-10-11 17:42:58 -06:00
..
6pack.c	hamradio: 6pack: fix array-index-out-of-bounds in decode_std_command()	2022-06-17 11:39:46 +01:00
baycom_epp.c	treewide: use get_random_{u8,u16}() when possible, part 1	2022-10-11 17:42:58 -06:00
baycom_par.c	hamradio: use ndo_siocdevprivate	2021-07-27 20:11:44 +01:00
baycom_ser_fdx.c	hamradio: use ndo_siocdevprivate	2021-07-27 20:11:44 +01:00
baycom_ser_hdx.c	hamradio: use ndo_siocdevprivate	2021-07-27 20:11:44 +01:00
bpqether.c	hamradio: use dev_addr_set() for setting device address	2021-10-13 09:41:37 -07:00
hdlcdrv.c	treewide: use get_random_{u8,u16}() when possible, part 1	2022-10-11 17:42:58 -06:00
Kconfig	net: hamradio: remove support for DMA SCC devices	2022-04-27 12:22:56 +01:00
Makefile	net: hamradio: remove support for DMA SCC devices	2022-04-27 12:22:56 +01:00
mkiss.c	TTY/Serial driver updates for 5.17-rc1	2022-01-12 11:21:52 -08:00
scc.c	net: Don't include filter.h from net/sock.h	2021-12-29 08:48:14 -08:00
yam.c	treewide: use get_random_{u8,u16}() when possible, part 1	2022-10-11 17:42:58 -06:00
z8530.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00