From 84bc4ba8168154fae0da7d56dcd11df0d4bc44f2 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Thu, 12 Dec 2019 16:47:21 +1030 Subject: [PATCH] obj-evax.c tidy This started out as fixing decode_16, which used a char to index a 256 byte decodings array. When char is signed that could result in an out of bounds array access. The rest of the patch is for consistency and just general cleanup. * config/obj-evax.c (crc32, encode_32, encode_16, decode_16): Remove unnecessary prototypes. (number_of_codings): Delete, use ARRAY_SIZE instead throughout. (codings, decodings): Make arrays of unsigned char. (crc32): Use unsigned variables. Delete unnecessary mask. (encode_32, encode_16): Return unsigned char*, and make static buffer an unsigned char array. (decode_16): Make arg an unsigned char*. Remove useless casts. (shorten_identifier): Use unsigned char crc_chars. (is_truncated_identifier): Make ptr an unsigned char*. --- gas/ChangeLog | 13 +++++++++++ gas/config/obj-evax.c | 51 +++++++++++++++++++------------------------ 2 files changed, 35 insertions(+), 29 deletions(-) diff --git a/gas/ChangeLog b/gas/ChangeLog index 700014d47f1..d8c5a17b3d3 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,16 @@ +2019-12-12 Alan Modra + + * config/obj-evax.c (crc32, encode_32, encode_16, decode_16): + Remove unnecessary prototypes. + (number_of_codings): Delete, use ARRAY_SIZE instead throughout. + (codings, decodings): Make arrays of unsigned char. + (crc32): Use unsigned variables. Delete unnecessary mask. + (encode_32, encode_16): Return unsigned char*, and make static + buffer an unsigned char array. + (decode_16): Make arg an unsigned char*. Remove useless casts. + (shorten_identifier): Use unsigned char crc_chars. + (is_truncated_identifier): Make ptr an unsigned char*. + 2019-12-11 Wilco Dijkstra * config/tc-arm.c (warn_on_restrict_it): Add new variable. diff --git a/gas/config/obj-evax.c b/gas/config/obj-evax.c index 75642d036db..dd090776320 100644 --- a/gas/config/obj-evax.c +++ b/gas/config/obj-evax.c @@ -30,10 +30,6 @@ #include "safe-ctype.h" static void s_evax_weak (int); -static unsigned int crc32 (unsigned char *, int); -static char *encode_32 (unsigned int); -static char *encode_16 (unsigned int); -static int decode_16 (const char *); const pseudo_typeS obj_pseudo_table[] = { @@ -338,19 +334,16 @@ evax_shorten_name (char *id) /* Table used to convert an integer into a string. */ -static const char codings[] = { +static const unsigned char codings[] = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '_'}; -/* The number of codings in the above table. */ -static const int number_of_codings = sizeof (codings) / sizeof (char); - /* Table used by decode_16 () to convert an encoded string back into an integer. */ -static char decodings[256]; +static unsigned char decodings[256]; /* Table used by the crc32 function to calculate the checksum. */ static unsigned int crc32_table[256] = {0, 0}; @@ -367,7 +360,7 @@ crc32 (unsigned char *buf, int len) if (! crc32_table[1]) { /* Initialize the CRC table and the decoding table. */ - int i, j; + unsigned int i, j; unsigned int c; for (i = 0; i < 256; i++) @@ -377,8 +370,8 @@ crc32 (unsigned char *buf, int len) crc32_table[i] = c; decodings[i] = 0; } - for (i = 0; i < number_of_codings; i++) - decodings[codings[i] & 255] = i; + for (i = 0; i < ARRAY_SIZE (codings); i++) + decodings[codings[i]] = i; } while (len--) @@ -391,34 +384,34 @@ crc32 (unsigned char *buf, int len) /* Encode the lower 32 bits of VALUE as a 5-character string. */ -static char * +static unsigned char * encode_32 (unsigned int value) { - static char res[6]; + static unsigned char res[6]; int x; res[5] = 0; for(x = 0; x < 5; x++) { - res[x] = codings[value % number_of_codings]; - value = value / number_of_codings; + res[x] = codings[value % ARRAY_SIZE (codings)]; + value = value / ARRAY_SIZE (codings); } return res; } /* Encode the lower 16 bits of VALUE as a 3-character string. */ -static char * +static unsigned char * encode_16 (unsigned int value) { - static char res[4]; + static unsigned char res[4]; int x; res[3] = 0; for(x = 0; x < 3; x++) { - res[x] = codings[value % number_of_codings]; - value = value / number_of_codings; + res[x] = codings[value % ARRAY_SIZE (codings)]; + value = value / ARRAY_SIZE (codings); } return res; } @@ -427,11 +420,11 @@ encode_16 (unsigned int value) 16-bit integer. */ static int -decode_16 (const char *string) +decode_16 (const unsigned char *string) { - return decodings[(int) string[2]] * number_of_codings * number_of_codings - + decodings[(int) string[1]] * number_of_codings - + decodings[(int) string[0]]; + return (decodings[string[2]] * ARRAY_SIZE (codings) * ARRAY_SIZE (codings) + + decodings[string[1]] * ARRAY_SIZE (codings) + + decodings[string[0]]); } /* ID_SUFFIX_LENGTH is used to determine how many characters in the @@ -452,14 +445,14 @@ static char * shorten_identifier (char *name) { int crc, len, sum, x, final_len; - char *crc_chars; + unsigned char *crc_chars; int suffix_length = ID_SUFFIX_LENGTH (name); if ((len = strlen (name)) <= MAX_LABEL_LENGTH) return name; final_len = MAX_LABEL_LENGTH - 2 - 5 - 3 - 3 - suffix_length; - crc = crc32 ((unsigned char *)name + final_len, + crc = crc32 ((unsigned char *) name + final_len, len - final_len - suffix_length); crc_chars = encode_32 (crc); sum = 0; @@ -487,7 +480,7 @@ shorten_identifier (char *name) static int is_truncated_identifier (char *id) { - char *ptr; + unsigned char *ptr; int len = strlen (id); /* If it's not exactly MAX_LABEL_LENGTH characters long, it can't be a truncated identifier. */ @@ -496,8 +489,8 @@ is_truncated_identifier (char *id) /* Start scanning backwards for a _h. */ len = len - 3 - 3 - 5 - 2; - ptr = id + len; - while (ptr >= id) + ptr = (unsigned char *) id + len; + while (ptr >= (unsigned char *) id) { if (ptr[0] == '_' && ptr[1] == 'h') { -- 2.30.2