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
..
ccids	dccp: tfrc: fix doc warnings in tfrc_equation.c	2021-06-10 14:08:49 -07:00
Kconfig	dccp: Replace HTTP links with HTTPS ones	2020-07-13 11:54:07 -07:00
Makefile	net: dccp: Remove dccpprobe module	2018-01-02 14:27:30 -05:00
ackvec.c	net: dccp: Fix most of the kerneldoc warnings	2020-10-30 12:08:54 -07:00
ackvec.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
ccid.c	net: dccp: Add __printf() markup to fix -Wsuggest-attribute=format	2020-10-30 11:31:46 -07:00
ccid.h	net: dccp: Replace zero-length array with flexible-array member	2020-02-28 12:08:37 -08:00
dccp.h	net: remove noblock parameter from recvmsg() entities	2022-04-12 15:00:25 +02:00
diag.c	inet_diag: Move the INET_DIAG_REQ_BYTECODE nlattr to cb->data	2020-02-27 18:50:19 -08:00
feat.c	dccp: Return the correct errno code	2021-02-06 11:15:28 -08:00
feat.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
input.c	net: dccp: Convert to use the preferred fallthrough macro	2020-08-22 12:38:34 -07:00
ipv4.c	treewide: use get_random_{u8,u16}() when possible, part 1	2022-10-11 17:42:58 -06:00
ipv6.c	net: Add a bhash2 table hashed by port and address	2022-08-24 19:30:07 -07:00
ipv6.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
minisocks.c	tcp: allocate tcp_death_row outside of struct netns_ipv4	2022-01-26 19:00:31 -08:00
options.c	net: dccp: Convert to use the preferred fallthrough macro	2020-08-22 12:38:34 -07:00
output.c	net: dccp: Fix most of the kerneldoc warnings	2020-10-30 12:08:54 -07:00
proto.c	tcp: Introduce optional per-netns ehash.	2022-09-20 10:21:50 -07:00
qpolicy.c	net: dccp: Fix most of the kerneldoc warnings	2020-10-30 12:08:54 -07:00
sysctl.c	proc/sysctl: add shared variables for range check	2019-07-18 17:08:07 -07:00
timer.c	net: sock: introduce sk_error_report	2021-06-29 11:28:21 -07:00
trace.h	net: dccp: Use memset_startat() for TP zeroing	2021-11-19 11:22:49 +00:00