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-rw-r--r--lib/vsprintf.c83
1 files changed, 78 insertions, 5 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index c3f36d415bdf..0e337541f005 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