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Rasmus Villemoes fb63362c63 lib: fix buggy strcmp and strncmp 
There are two problems with both strcmp and strncmp:

(1) The C standard is clear that the contents should be compared as
"unsigned char":

  The sign of a nonzero value returned by the comparison functions
  memcmp, strcmp, and strncmp is determined by the sign of the
  difference between the values of the first pair of characters (both
  interpreted as unsigned char) that differ in the objects being
  compared.

(2) The difference between two char (or unsigned char) values can
range from -255 to +255; so that's (due to integer promotion) the
range of values we could get in the *cs-*ct expressions, but when that
is then shoe-horned into an 8-bit quantity the sign may of course
change.

The impact is somewhat limited by the way these functions
are used in practice:

- Most of the time, one is only interested in equality (or for
  strncmp, "starts with"), and the existing functions do correctly
  return 0 if and only if the strings are equal [for strncmp, up to
  the given bound].

- Also most of the time, the strings being compared only consist of
  ASCII characters, i.e. have values in the range [0, 127], and in
  that case it doesn't matter if they are interpreted as signed or
  unsigned char, and the possible difference range is bounded to
  [-127, 127] which does fit the signed char.

For size, one could implement strcmp() in terms of strncmp() - just
make it "return strncmp(a, b, (size_t)-1);". However, performance of
strcmp() does matter somewhat, since it is used all over when parsing
and matching DT nodes and properties, so let's find some other place
to save those ~30 bytes.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
2022-10-27 09:10:08 -04:00
..
acpi dm: treewide: Use uclass_first_device_err when accessing one device 2022-10-17 21:17:12 -06:00
aes tools: avoid OpenSSL deprecation warnings 2021-12-26 06:57:20 +01:00
at91 SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
blake2 lib: add BLAKE2 hash support 2022-01-18 08:31:02 -05:00
bzip2 cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
crypt lib: crypt: fix selecting a non-existent option 2022-10-11 15:40:48 -04:00
crypto Merge branch 'next' 2022-07-11 14:58:57 -04:00
dhry global: Convert simple_strtoul() with decimal to dectoul() 2021-08-02 13:32:14 -04:00
ecdsa spl: Ensure all SPL symbols in Kconfig have some SPL dependency 2022-07-07 09:29:08 -04:00
efi lib: fix selection of CONFIG_CHARSET 2022-05-03 21:39:22 +02:00
efi_driver efi_driver: use efi_close_protocol 2022-10-10 16:34:26 +02:00
efi_loader dm: treewide: Use uclass_first_device_err when accessing one device 2022-10-17 21:17:12 -06:00
efi_selftest efi_selftest: rename event_notify 2022-10-06 22:54:58 +02:00
libavb common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
libfdt fdt_region: move fdt_region.c to common/ from lib/libfdt/ 2020-04-26 14:23:55 -06:00
lzma cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
lzo SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
optee fdtdec: Support reserved-memory flags 2021-10-13 14:18:30 -07:00
rsa lib: rsa: fix padding_pss_verify 2022-09-15 09:57:11 -04:00
zlib cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
zstd doc: replace @return by Return: 2022-01-19 18:11:34 +01:00
.gitignore lib: ignore oid_registry_data.c file 2020-01-22 17:47:57 -05:00
abuf.c abuf: Correct a corner case with abuf_realloc() 2022-04-06 14:01:42 -04:00
addr_map.c addrmap: Support on sandbox 2022-07-26 02:30:56 -06:00
aes.c common: Drop display_options.h from common header 2022-08-10 13:46:55 -04:00
asm-offsets.c arm64: Add missing GD_FLG_SKIP_RELOC handling 2021-11-18 18:20:19 -05:00
asn1_decoder.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
bch.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
binman.c doc: replace @return by Return: 2022-01-19 18:11:34 +01:00
bitrev.c lib: bitrev: Sync with Linux kernel v4.17 2018-09-18 00:01:18 -06:00
charset.c lib/charset: add u16_strlcat() function 2022-05-03 21:39:22 +02:00
circbuf.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
crc7.c lib: add crc7 from Linux 2011-01-18 23:38:08 +01:00
crc8.c common: Drop linux/crc8.h 2019-12-02 18:23:07 -05:00
crc16-ccitt.c crc16-ccitt: Rename file with CRC-16-CCITT implementation to crc16-ccitt.c 2022-04-21 14:32:40 -04:00
crc16.c crc16: Move standard CRC-16 implementation from ubifs to lib 2022-04-21 14:32:40 -04:00
crc32.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
crc32c.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
ctype.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
date.c lib/date: Make rtc_mktime and mktime64 Y2038-ready 2022-05-05 15:06:02 -04:00
display_options.c display_options: print_size: Fix order overflow 2022-09-23 15:13:18 -04:00
div64.c common: Drop linux/bitops.h from common header 2020-05-18 21:19:23 -04:00
elf.c video: Renname vbe.h to vesa.h 2022-08-12 08:14:23 -04:00
errno_str.c lib: errno: sync error codes 2019-10-31 07:22:53 -04:00
errno.c sandbox: errno: avoid conflict with libc's errno 2021-05-24 14:21:30 -04:00
fdt-libcrypto.c lib/rsa: Make fdt_add_bignum() available outside of RSA code 2021-04-14 15:06:08 -04:00
fdtdec_common.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
fdtdec_test.c fdtdec: Support reserved-memory flags 2021-10-13 14:18:30 -07:00
fdtdec.c dm: core: Provide a way to reset the device tree 2022-09-29 22:43:43 -04:00
getopt.c lib: Add getopt 2020-10-30 10:56:11 -04:00
gunzip.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
gzip.c common: Move gzip functions into a new gzip header 2019-08-11 16:43:41 -04:00
hang.c serial: Rename SERIAL_SUPPORT to SERIAL 2021-09-04 12:26:01 -04:00
hash-checksum.c image: Drop unnecessary #ifdefs from image.h 2021-10-08 15:53:27 -04:00
hashtable.c Convert CONFIG_ENV_MIN_ENTRIES et al to Kconfig 2022-06-28 17:11:48 -04:00
hexdump.c hexdump: Allow ctrl-c to interrupt output 2021-06-08 11:39:09 -04:00
image-sparse.c lib: sparse: Make CHUNK_TYPE_RAW buffer aligned 2022-01-14 12:26:30 -05:00
Kconfig Convert CONFIG_SYS_FDT_PAD to Kconfig 2022-08-12 16:10:50 -04:00
ldiv.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
linux_compat.c common: Drop net.h from common header 2020-05-18 17:33:31 -04:00
linux_string.c Make linux kernel string funcs available to tools 2012-12-13 11:46:07 -07:00
list_sort.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
lmb.c lmb: Fix LMB_MEMORY_REGIONS flag usage 2022-08-10 13:38:30 -04:00
lz4_wrapper.c lz4: Fix compile warning comparison of distinct pointer types 2022-08-10 13:46:55 -04:00
lz4.c lib/lz4: update LZ4 decompressor module 2022-03-15 16:19:29 -04:00
Makefile arm: samsung: Remove dead LCD code 2022-06-28 17:03:32 -04:00
md5.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
membuff.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
net_utils.c global: Convert simple_strtoul() with decimal to dectoul() 2021-08-02 13:32:14 -04:00
of_live.c dm: core: Avoid creating a name property when unflattening 2022-09-29 16:11:14 -04:00
oid_registry.c lib: add oid registry utility 2019-12-06 16:44:20 -05:00
panic.c common: Drop linux/delay.h from common header 2020-05-18 21:19:23 -04:00
physmem.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
qsort.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rand.c common: Move random-number functions into their own header 2019-12-02 18:23:07 -05:00
rational.c lib: rational: copy the rational fraction lib routines from Linux 2021-06-11 16:34:52 +05:30
rbtree.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
rc4.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
rtc-lib.c lib: move rtc-lib.c to lib 2021-07-14 16:57:35 -04:00
sha1.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
sha256.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
sha512.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
slre.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
smbios-parser.c efi_loader: add SMBIOS table measurement 2021-10-26 17:58:14 +02:00
smbios.c smbios: error handling for invalid addresses 2021-07-24 10:49:51 +02:00
sscanf.c xen: Code style conformity 2020-08-24 14:11:31 -04:00
string.c lib: fix buggy strcmp and strncmp 2022-10-27 09:10:08 -04:00
strto.c lib: Add a way to find the postiion of a trailing number 2022-04-25 10:00:03 -04:00
tables_csum.c SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
time.c cyclic: Use schedule() instead of WATCHDOG_RESET() 2022-09-18 10:26:33 +02:00
tiny-printf.c net: Rename SPL_NET_SUPPORT to SPL_NET 2021-09-04 12:48:53 -04:00
tpm_api.c tpm: Require a digest source when extending the PCR 2022-09-03 16:53:58 +03:00
tpm-common.c tpm: Check outgoing command size 2021-07-15 18:42:05 -04:00
tpm-utils.h doc: replace @return by Return: 2022-01-19 18:11:34 +01:00
tpm-v1.c tpm: Correct the permissions command in TPMv1 2022-09-03 16:54:02 +03:00
tpm-v2.c tpm: Allow committing non-volatile data 2022-09-03 16:59:05 +03:00
trace.c treewide: Convert macro and uses of __section(foo) to __section("foo") 2021-05-24 14:21:30 -04:00
uuid.c efi: Create ECPT table 2022-09-03 09:35:48 +02:00
vsprintf.c lib: fix snprintf() for UTF-16 strings 2022-02-05 20:20:01 +01:00
xxhash.c lib: Add xxhash support 2019-05-05 08:48:50 -04:00