From 76597ff989a1fbaa9b9a1e54007cd759bf257ab7 Mon Sep 17 00:00:00 2001 From: Andrei Emeltchenko Date: Mon, 30 Jul 2012 14:40:23 -0700 Subject: vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko Cc: Joe Perches Cc: Marcel Holtmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/vsprintf.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) (limited to 'lib/vsprintf.c') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index c3f36d415bd..736974576e2 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -662,15 +662,28 @@ 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 +946,7 @@ 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 @@ -995,7 +1009,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, return resource_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 -- cgit v1.2.3-70-g09d2 From 80f548e04d0b1d67d4fa8f59dbecc247f7b71c92 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Mon, 30 Jul 2012 14:40:25 -0700 Subject: lib/vsprintf.c: remind people to update Documentation/printk-formats.txt when adding printk formats Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/vsprintf.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'lib/vsprintf.c') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 736974576e2..a0b5f15c92c 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1297,6 +1297,8 @@ qualifier: * case. * %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 -- cgit v1.2.3-70-g09d2 From 3715c5309f6d175c3053672b73fd4f73be16fd07 Mon Sep 17 00:00:00 2001 From: Dan Rosenberg Date: Mon, 30 Jul 2012 14:40:26 -0700 Subject: lib/vsprintf.c: kptr_restrict: fix pK-error in SysRq show-all-timers(Q) When using ALT+SysRq+Q all the pointers are replaced with "pK-error" like this: [23153.208033] .base: pK-error with echo h > /proc/sysrq-trigger it works: [23107.776363] .base: ffff88023e60d540 The intent behind this behavior was to return "pK-error" in cases where the %pK format specifier was used in interrupt context, because the CAP_SYSLOG check wouldn't be meaningful. Clearly this should only apply when kptr_restrict is actually enabled though. Reported-by: Stevie Trujillo Signed-off-by: Dan Rosenberg Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/vsprintf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'lib/vsprintf.c') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index a0b5f15c92c..225aa683e17 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1045,7 +1045,8 @@ 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); -- cgit v1.2.3-70-g09d2 From 31550a16a5d2af859e8a11839e8c6c6c9c92dfa7 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Mon, 30 Jul 2012 14:40:27 -0700 Subject: vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/printk-formats.txt | 10 ++++++++ lib/vsprintf.c | 55 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+) (limited to 'lib/vsprintf.c') diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt index d8d168fa79d..7561d7ed8e1 100644 --- a/Documentation/printk-formats.txt +++ b/Documentation/printk-formats.txt @@ -53,6 +53,16 @@ Struct Resources: For printing struct resources. The 'R' and 'r' specifiers result in a printed resource with ('R') or without ('r') a decoded flags member. +Raw buffer as a hex string: + %*ph 00 01 02 ... 3f + %*phC 00:01:02: ... :3f + %*phD 00-01-02- ... -3f + %*phN 000102 ... 3f + + For printing a small buffers (up to 64 bytes long) as a hex string with + certain separator. For the larger buffers consider to use + print_hex_dump(). + MAC/FDDI addresses: %pM 00:01:02:03:04:05 diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 225aa683e17..0e337541f00 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -654,6 +654,50 @@ char *resource_string(char *buf, char *end, struct resource *res, return string(buf, end, sym, spec); } +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) @@ -974,6 +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 @@ -1007,6 +1058,8 @@ 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) */ @@ -1296,6 +1349,8 @@ 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 ** -- cgit v1.2.3-70-g09d2