diff options
Diffstat (limited to 'lib/vsprintf.c')
| -rw-r--r-- | lib/vsprintf.c | 83 |
1 files changed, 78 insertions, 5 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index c3f36d415bd..0e337541f00 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -655,6 +655,50 @@ char *resource_string(char *buf, char *end, struct resource *res, } static noinline_for_stack +char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, + const char *fmt) +{ + int i, len = 1; /* if we pass '%ph[CDN]', field witdh remains + negative value, fallback to the default */ + char separator; + + if (spec.field_width == 0) + /* nothing to print */ + return buf; + + if (ZERO_OR_NULL_PTR(addr)) + /* NULL pointer */ + return string(buf, end, NULL, spec); + + switch (fmt[1]) { + case 'C': + separator = ':'; + break; + case 'D': + separator = '-'; + break; + case 'N': + separator = 0; + break; + default: + separator = ' '; + break; + } + + if (spec.field_width > 0) + len = min_t(int, spec.field_width, 64); + + for (i = 0; i < len && buf < end - 1; i++) { + buf = hex_byte_pack(buf, addr[i]); + + if (buf < end && separator && i != len - 1) + *buf++ = separator; + } + + return buf; +} + +static noinline_for_stack char *mac_address_string(char *buf, char *end, u8 *addr, struct printf_spec spec, const char *fmt) { @@ -662,15 +706,28 @@ char *mac_address_string(char *buf, char *end, u8 *addr, char *p = mac_addr; int i; char separator; + bool reversed = false; - if (fmt[1] == 'F') { /* FDDI canonical format */ + switch (fmt[1]) { + case 'F': separator = '-'; - } else { + break; + + case 'R': + reversed = true; + /* fall through */ + + default: separator = ':'; + break; } for (i = 0; i < 6; i++) { - p = hex_byte_pack(p, addr[i]); + if (reversed) + p = hex_byte_pack(p, addr[5 - i]); + else + p = hex_byte_pack(p, addr[i]); + if (fmt[0] == 'M' && i != 5) *p++ = separator; } @@ -933,6 +990,7 @@ int kptr_restrict __read_mostly; * - 'm' For a 6-byte MAC address, it prints the hex address without colons * - 'MF' For a 6-byte MAC FDDI address, it prints the address * with a dash-separated hex notation + * - '[mM]R For a 6-byte MAC address, Reverse order (Bluetooth) * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) * IPv6 uses colon separated network-order 16 bit hex with leading 0's @@ -960,6 +1018,13 @@ int kptr_restrict __read_mostly; * correctness of the format string and va_list arguments. * - 'K' For a kernel pointer that should be hidden from unprivileged users * - 'NF' For a netdev_features_t + * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with + * a certain separator (' ' by default): + * C colon + * D dash + * N no separator + * The maximum supported length is 64 bytes of the input. Consider + * to use print_hex_dump() for the larger input. * * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 * function pointers are really function descriptors, which contain a @@ -993,9 +1058,12 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, case 'R': case 'r': return resource_string(buf, end, ptr, spec, fmt); + case 'h': + return hex_string(buf, end, ptr, spec, fmt); case 'M': /* Colon separated: 00:01:02:03:04:05 */ case 'm': /* Contiguous: 000102030405 */ - /* [mM]F (FDDI, bit reversed) */ + /* [mM]F (FDDI) */ + /* [mM]R (Reverse order; Bluetooth) */ return mac_address_string(buf, end, ptr, spec, fmt); case 'I': /* Formatted IP supported * 4: 1.2.3.4 @@ -1030,7 +1098,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, * %pK cannot be used in IRQ context because its test * for CAP_SYSLOG would be meaningless. */ - if (in_irq() || in_serving_softirq() || in_nmi()) { + if (kptr_restrict && (in_irq() || in_serving_softirq() || + in_nmi())) { if (spec.field_width == -1) spec.field_width = default_width; return string(buf, end, "pK-error", spec); @@ -1280,8 +1349,12 @@ qualifier: * %pI6c print an IPv6 address as specified by RFC 5952 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper * case. + * %*ph[CDN] a variable-length hex string with a separator (supports up to 64 + * bytes of the input) * %n is ignored * + * ** Please update Documentation/printk-formats.txt when making changes ** + * * The return value is the number of characters which would * be generated for the given input, excluding the trailing * '\0', as per ISO C99. If you want to have the exact |