diff options
Diffstat (limited to 'lib/vsprintf.c')
| -rw-r--r-- | lib/vsprintf.c | 160 |
1 files changed, 146 insertions, 14 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 48ff9c36644d..ccb664b54280 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -35,6 +35,8 @@ #include <linux/blkdev.h> #endif +#include "../mm/internal.h" /* For the trace_print_flags arrays */ + #include <asm/page.h> /* for PAGE_SIZE */ #include <asm/sections.h> /* for dereference_function_descriptor() */ #include <asm/byteorder.h> /* cpu_to_le16 */ @@ -1407,6 +1409,72 @@ char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, } } +static +char *format_flags(char *buf, char *end, unsigned long flags, + const struct trace_print_flags *names) +{ + unsigned long mask; + const struct printf_spec strspec = { + .field_width = -1, + .precision = -1, + }; + const struct printf_spec numspec = { + .flags = SPECIAL|SMALL, + .field_width = -1, + .precision = -1, + .base = 16, + }; + + for ( ; flags && names->name; names++) { + mask = names->mask; + if ((flags & mask) != mask) + continue; + + buf = string(buf, end, names->name, strspec); + + flags &= ~mask; + if (flags) { + if (buf < end) + *buf = '|'; + buf++; + } + } + + if (flags) + buf = number(buf, end, flags, numspec); + + return buf; +} + +static noinline_for_stack +char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt) +{ + unsigned long flags; + const struct trace_print_flags *names; + + switch (fmt[1]) { + case 'p': + flags = *(unsigned long *)flags_ptr; + /* Remove zone id */ + flags &= (1UL << NR_PAGEFLAGS) - 1; + names = pageflag_names; + break; + case 'v': + flags = *(unsigned long *)flags_ptr; + names = vmaflag_names; + break; + case 'g': + flags = *(gfp_t *)flags_ptr; + names = gfpflag_names; + break; + default: + WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]); + return buf; + } + + return format_flags(buf, end, flags, names); +} + int kptr_restrict __read_mostly; /* @@ -1495,6 +1563,11 @@ int kptr_restrict __read_mostly; * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address * (legacy clock framework) of the clock * - 'Cr' For a clock, it prints the current rate of the clock + * - 'G' For flags to be printed as a collection of symbolic strings that would + * construct the specific value. Supported flags given by option: + * p page flags (see struct page) given as pointer to unsigned long + * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t + * v vma flags (VM_*) given as pointer to unsigned long * * ** Please update also Documentation/printk-formats.txt when making changes ** * @@ -1590,22 +1663,23 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, return buf; } case 'K': - /* - * %pK cannot be used in IRQ context because its test - * for CAP_SYSLOG would be meaningless. - */ - 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); - } - switch (kptr_restrict) { case 0: /* Always print %pK values */ break; case 1: { + const struct cred *cred; + + /* + * kptr_restrict==1 cannot be used in IRQ context + * because its test for CAP_SYSLOG would be meaningless. + */ + if (in_irq() || in_serving_softirq() || in_nmi()) { + if (spec.field_width == -1) + spec.field_width = default_width; + return string(buf, end, "pK-error", spec); + } + /* * Only print the real pointer value if the current * process has CAP_SYSLOG and is running with the @@ -1615,8 +1689,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, * leak pointer values if a binary opens a file using * %pK and then elevates privileges before reading it. */ - const struct cred *cred = current_cred(); - + cred = current_cred(); if (!has_capability_noaudit(current, CAP_SYSLOG) || !uid_eq(cred->euid, cred->uid) || !gid_eq(cred->egid, cred->gid)) @@ -1648,6 +1721,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, return bdev_name(buf, end, ptr, spec, fmt); #endif + case 'G': + return flags_string(buf, end, ptr, fmt); } spec.flags |= SMALL; if (spec.field_width == -1) { @@ -2565,8 +2640,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args) if (*fmt == '*') { if (!*str) break; - while (!isspace(*fmt) && *fmt != '%' && *fmt) + while (!isspace(*fmt) && *fmt != '%' && *fmt) { + /* '%*[' not yet supported, invalid format */ + if (*fmt == '[') + return num; fmt++; + } while (!isspace(*str) && *str) str++; continue; @@ -2639,6 +2718,59 @@ int vsscanf(const char *buf, const char *fmt, va_list args) num++; } continue; + /* + * Warning: This implementation of the '[' conversion specifier + * deviates from its glibc counterpart in the following ways: + * (1) It does NOT support ranges i.e. '-' is NOT a special + * character + * (2) It cannot match the closing bracket ']' itself + * (3) A field width is required + * (4) '%*[' (discard matching input) is currently not supported + * + * Example usage: + * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", + * buf1, buf2, buf3); + * if (ret < 3) + * // etc.. + */ + case '[': + { + char *s = (char *)va_arg(args, char *); + DECLARE_BITMAP(set, 256) = {0}; + unsigned int len = 0; + bool negate = (*fmt == '^'); + + /* field width is required */ + if (field_width == -1) + return num; + + if (negate) + ++fmt; + + for ( ; *fmt && *fmt != ']'; ++fmt, ++len) + set_bit((u8)*fmt, set); + + /* no ']' or no character set found */ + if (!*fmt || !len) + return num; + ++fmt; + + if (negate) { + bitmap_complement(set, set, 256); + /* exclude null '\0' byte */ + clear_bit(0, set); + } + + /* match must be non-empty */ + if (!test_bit((u8)*str, set)) + return num; + + while (test_bit((u8)*str, set) && field_width--) + *s++ = *str++; + *s = '\0'; + ++num; + } + continue; case 'o': base = 8; break; |