From: Alastair D'Silva <alast...@d-silva.org> This patch removes the hardcoded row limits and allows for other lengths. These lengths must still be a multiple of groupsize.
This allows structs that are not 16/32 bytes to display on a single line. This patch also expands the self-tests to test row sizes up to 64 bytes (though they can now be arbitrarily long). Signed-off-by: Alastair D'Silva <alast...@d-silva.org> --- lib/hexdump.c | 48 ++++++++++++++++++++++++++++-------------- lib/test_hexdump.c | 52 ++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 75 insertions(+), 25 deletions(-) diff --git a/lib/hexdump.c b/lib/hexdump.c index 81b70ed37209..3943507bc0e9 100644 --- a/lib/hexdump.c +++ b/lib/hexdump.c @@ -12,6 +12,7 @@ #include <linux/errno.h> #include <linux/kernel.h> #include <linux/export.h> +#include <linux/slab.h> #include <asm/unaligned.h> const char hex_asc[] = "0123456789abcdef"; @@ -80,14 +81,15 @@ EXPORT_SYMBOL(bin2hex); * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory * @buf: data blob to dump * @len: number of bytes in the @buf - * @rowsize: number of bytes to print per line; must be 16 or 32 + * @rowsize: number of bytes to print per line; must be a multiple of groupsize * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1) * @linebuf: where to put the converted data * @linebuflen: total size of @linebuf, including space for terminating NUL * @ascii: include ASCII after the hex output * - * hex_dump_to_buffer() works on one "line" of output at a time, i.e., - * 16 or 32 bytes of input data converted to hex + ASCII output. + * hex_dump_to_buffer() works on one "line" of output at a time, converting + * <groupsize> bytes of input to hexadecimal (and optionally printable ASCII) + * until <rowsize> bytes have been emitted. * * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data * to a hex + ASCII dump at the supplied memory location. @@ -116,16 +118,17 @@ int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize, int ascii_column; int ret; - if (rowsize != 16 && rowsize != 32) - rowsize = 16; - - if (len > rowsize) /* limit to one line at a time */ - len = rowsize; if (!is_power_of_2(groupsize) || groupsize > 8) groupsize = 1; if ((len % groupsize) != 0) /* no mixed size output */ groupsize = 1; + if (rowsize % groupsize) + rowsize -= rowsize % groupsize; + + if (len > rowsize) /* limit to one line at a time */ + len = rowsize; + ngroups = len / groupsize; ascii_column = rowsize * 2 + rowsize / groupsize + 1; @@ -216,7 +219,7 @@ EXPORT_SYMBOL(hex_dump_to_buffer); * caller supplies trailing spaces for alignment if desired * @prefix_type: controls whether prefix of an offset, address, or none * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE) - * @rowsize: number of bytes to print per line; must be 16 or 32 + * @rowsize: number of bytes to print per line; must be a multiple of groupsize * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1) * @buf: data blob to dump * @len: number of bytes in the @buf @@ -226,10 +229,9 @@ EXPORT_SYMBOL(hex_dump_to_buffer); * to the kernel log at the specified kernel log level, with an optional * leading prefix. * - * print_hex_dump() works on one "line" of output at a time, i.e., - * 16 or 32 bytes of input data converted to hex + ASCII output. * print_hex_dump() iterates over the entire input @buf, breaking it into - * "line size" chunks to format and print. + * lines of rowsize/groupsize groups of input data converted to hex + + * (optionally) ASCII output. * * E.g.: * print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS, @@ -246,17 +248,29 @@ void print_hex_dump(const char *level, const char *prefix_str, int prefix_type, { const u8 *ptr = buf; int i, linelen, remaining = len; - unsigned char linebuf[32 * 3 + 2 + 32 + 1]; + unsigned char *linebuf; + unsigned int linebuf_len; - if (rowsize != 16 && rowsize != 32) - rowsize = 16; + if (rowsize % groupsize) + rowsize -= rowsize % groupsize; + + /* Worst case line length: + * 2 hex chars + space per byte in, 2 spaces, 1 char per byte in, NULL + */ + linebuf_len = rowsize * 3 + 2 + rowsize + 1; + linebuf = kzalloc(linebuf_len, GFP_KERNEL); + if (!linebuf) { + printk("%s%shexdump: Could not alloc %u bytes for buffer\n", + level, prefix_str, linebuf_len); + return; + } for (i = 0; i < len; i += rowsize) { linelen = min(remaining, rowsize); remaining -= rowsize; hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, - linebuf, sizeof(linebuf), ascii); + linebuf, linebuf_len, ascii); switch (prefix_type) { case DUMP_PREFIX_ADDRESS: @@ -271,6 +285,8 @@ void print_hex_dump(const char *level, const char *prefix_str, int prefix_type, break; } } + + kfree(linebuf); } EXPORT_SYMBOL(print_hex_dump); diff --git a/lib/test_hexdump.c b/lib/test_hexdump.c index d78ddd62ffd0..6ab75a209b43 100644 --- a/lib/test_hexdump.c +++ b/lib/test_hexdump.c @@ -14,15 +14,25 @@ static const unsigned char data_b[] = { '\x70', '\xba', '\xc4', '\x24', '\x7d', '\x83', '\x34', '\x9b', /* 08 - 0f */ '\xa6', '\x9c', '\x31', '\xad', '\x9c', '\x0f', '\xac', '\xe9', /* 10 - 17 */ '\x4c', '\xd1', '\x19', '\x99', '\x43', '\xb1', '\xaf', '\x0c', /* 18 - 1f */ + '\x00', '\x01', '\x02', '\x03', '\x04', '\x05', '\x06', '\x07', /* 20 - 27 */ + '\x0f', '\x0e', '\x0d', '\x0c', '\x0b', '\x0a', '\x09', '\x08', /* 28 - 2f */ + '\x10', '\x11', '\x12', '\x13', '\x14', '\x15', '\x16', '\x17', /* 30 - 37 */ + '\x1f', '\x1e', '\x1d', '\x1c', '\x1b', '\x1a', '\x19', '\x18', /* 38 - 3f */ }; -static const unsigned char data_a[] = ".2.{....p..$}.4...1.....L...C..."; +static const unsigned char data_a[] = ".2.{....p..$}.4...1.....L...C..." + "................................"; static const char * const test_data_1[] __initconst = { "be", "32", "db", "7b", "0a", "18", "93", "b2", "70", "ba", "c4", "24", "7d", "83", "34", "9b", "a6", "9c", "31", "ad", "9c", "0f", "ac", "e9", "4c", "d1", "19", "99", "43", "b1", "af", "0c", + "00", "01", "02", "03", "04", "05", "06", "07", + "0f", "0e", "0d", "0c", "0b", "0a", "09", "08", + "10", "11", "12", "13", "14", "15", "16", "17", + "1f", "1e", "1d", "1c", "1b", "1a", "19", "18", + NULL }; static const char * const test_data_2_le[] __initconst = { @@ -30,6 +40,11 @@ static const char * const test_data_2_le[] __initconst = { "ba70", "24c4", "837d", "9b34", "9ca6", "ad31", "0f9c", "e9ac", "d14c", "9919", "b143", "0caf", + "0100", "0302", "0504", "0706", + "0e0f", "0c0d", "0a0b", "0809", + "1110", "1312", "1514", "1716", + "1e1f", "1c1d", "1a1b", "1819", + NULL }; static const char * const test_data_2_be[] __initconst = { @@ -37,26 +52,43 @@ static const char * const test_data_2_be[] __initconst = { "70ba", "c424", "7d83", "349b", "a69c", "31ad", "9c0f", "ace9", "4cd1", "1999", "43b1", "af0c", + "0001", "0203", "0405", "0607", + "0f0e", "0d0c", "0b0a", "0908", + "1011", "1213", "1415", "1617", + "1f1e", "1d1c", "1b1a", "1918", + NULL }; static const char * const test_data_4_le[] __initconst = { "7bdb32be", "b293180a", "24c4ba70", "9b34837d", "ad319ca6", "e9ac0f9c", "9919d14c", "0cafb143", + "03020100", "07060504", "0c0d0e0f", "08090a0b", + "13121110", "17161514", "1c1d1e1f", "18191a1b", + NULL }; static const char * const test_data_4_be[] __initconst = { "be32db7b", "0a1893b2", "70bac424", "7d83349b", "a69c31ad", "9c0face9", "4cd11999", "43b1af0c", + "00010203", "04050607", "0f0e0d0c", "0b0a0908", + "10111213", "14151617", "1f1e1d1c", "1b1a1918", + NULL }; static const char * const test_data_8_le[] __initconst = { "b293180a7bdb32be", "9b34837d24c4ba70", "e9ac0f9cad319ca6", "0cafb1439919d14c", + "0706050403020100", "08090a0b0c0d0e0f", + "1716151413121110", "18191a1b1c1d1e1f", + NULL }; static const char * const test_data_8_be[] __initconst = { "be32db7b0a1893b2", "70bac4247d83349b", "a69c31ad9c0face9", "4cd1199943b1af0c", + "0001020304050607", "0f0e0d0c0b0a0908", + "1011121314151617", "1f1e1d1c1b1a1918", + NULL }; #define FILL_CHAR '#' @@ -75,9 +107,6 @@ static void __init test_hexdump_prepare_test(size_t len, int rowsize, unsigned int i; const bool is_be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN); - if (rs != 16 && rs != 32) - rs = 16; - if (l > rs) l = rs; @@ -97,7 +126,12 @@ static void __init test_hexdump_prepare_test(size_t len, int rowsize, p = test; for (i = 0; i < l / gs; i++) { const char *q = *result++; - size_t amount = strlen(q); + size_t amount; + + if (!q) + break; + + amount = strlen(q); memcpy(p, q, amount); p += amount; @@ -120,7 +154,7 @@ static void __init test_hexdump_prepare_test(size_t len, int rowsize, *p = '\0'; } -#define TEST_HEXDUMP_BUF_SIZE (32 * 3 + 2 + 32 + 1) +#define TEST_HEXDUMP_BUF_SIZE (64 * 3 + 2 + 64 + 1) static void __init test_hexdump(size_t len, int rowsize, int groupsize, bool ascii) @@ -215,7 +249,7 @@ static void __init test_hexdump_overflow(size_t buflen, size_t len, static void __init test_hexdump_overflow_set(size_t buflen, bool ascii) { unsigned int i = 0; - int rs = (get_random_int() % 2 + 1) * 16; + int rs = (get_random_int() % 4 + 1) * 16; do { int gs = 1 << i; @@ -230,11 +264,11 @@ static int __init test_hexdump_init(void) unsigned int i; int rowsize; - rowsize = (get_random_int() % 2 + 1) * 16; + rowsize = (get_random_int() % 4 + 1) * 16; for (i = 0; i < 16; i++) test_hexdump_set(rowsize, false); - rowsize = (get_random_int() % 2 + 1) * 16; + rowsize = (get_random_int() % 4 + 1) * 16; for (i = 0; i < 16; i++) test_hexdump_set(rowsize, true); -- 2.21.0