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authorLinus Torvalds <torvalds@linux-foundation.org>2021-06-29 21:07:18 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2021-06-29 21:07:18 +0200
commite563592c3e4296780e5a184a917b8b86e126f0b3 (patch)
tree3f52a0f2976dd29505f05a94b1ff80b9c6c8f517 /lib/vsprintf.c
parentMerge tag 'hyperv-next-signed-20210629' of git://git.kernel.org/pub/scm/linux... (diff)
parentMerge branch 'printk-rework' into for-linus (diff)
downloadlinux-e563592c3e4296780e5a184a917b8b86e126f0b3.tar.xz
linux-e563592c3e4296780e5a184a917b8b86e126f0b3.zip
Merge tag 'printk-for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek: - Add %pt[RT]s modifier to vsprintf(). It overrides ISO 8601 separator by using ' ' (space). It produces "YYYY-mm-dd HH:MM:SS" instead of "YYYY-mm-ddTHH:MM:SS". - Correctly parse long row of numbers by sscanf() when using the field width. Add extensive sscanf() selftest. - Generalize re-entrant CPU lock that has already been used to serialize dump_stack() output. It is part of the ongoing printk rework. It will allow to remove the obsoleted printk_safe buffers and introduce atomic consoles. - Some code clean up and sparse warning fixes. * tag 'printk-for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: fix cpu lock ordering lib/dump_stack: move cpu lock to printk.c printk: Remove trailing semicolon in macros random32: Fix implicit truncation warning in prandom_seed_state() lib: test_scanf: Remove pointless use of type_min() with unsigned types selftests: lib: Add wrapper script for test_scanf lib: test_scanf: Add tests for sscanf number conversion lib: vsprintf: Fix handling of number field widths in vsscanf lib: vsprintf: scanf: Negative number must have field width > 1 usb: host: xhci-tegra: Switch to use %ptTs nilfs2: Switch to use %ptTs kdb: Switch to use %ptTs lib/vsprintf: Allow to override ISO 8601 date and time separator
Diffstat (limited to 'lib/vsprintf.c')
-rw-r--r--lib/vsprintf.c110
1 files changed, 70 insertions, 40 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index f0c35d9b65bf..ea65ec51e63b 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -53,6 +53,31 @@
#include <linux/string_helpers.h>
#include "kstrtox.h"
+static unsigned long long simple_strntoull(const char *startp, size_t max_chars,
+ char **endp, unsigned int base)
+{
+ const char *cp;
+ unsigned long long result = 0ULL;
+ size_t prefix_chars;
+ unsigned int rv;
+
+ cp = _parse_integer_fixup_radix(startp, &base);
+ prefix_chars = cp - startp;
+ if (prefix_chars < max_chars) {
+ rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars);
+ /* FIXME */
+ cp += (rv & ~KSTRTOX_OVERFLOW);
+ } else {
+ /* Field too short for prefix + digit, skip over without converting */
+ cp = startp + max_chars;
+ }
+
+ if (endp)
+ *endp = (char *)cp;
+
+ return result;
+}
+
/**
* simple_strtoull - convert a string to an unsigned long long
* @cp: The start of the string
@@ -63,18 +88,7 @@
*/
unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
{
- unsigned long long result;
- unsigned int rv;
-
- cp = _parse_integer_fixup_radix(cp, &base);
- rv = _parse_integer(cp, base, &result);
- /* FIXME */
- cp += (rv & ~KSTRTOX_OVERFLOW);
-
- if (endp)
- *endp = (char *)cp;
-
- return result;
+ return simple_strntoull(cp, INT_MAX, endp, base);
}
EXPORT_SYMBOL(simple_strtoull);
@@ -109,6 +123,21 @@ long simple_strtol(const char *cp, char **endp, unsigned int base)
}
EXPORT_SYMBOL(simple_strtol);
+static long long simple_strntoll(const char *cp, size_t max_chars, char **endp,
+ unsigned int base)
+{
+ /*
+ * simple_strntoull() safely handles receiving max_chars==0 in the
+ * case cp[0] == '-' && max_chars == 1.
+ * If max_chars == 0 we can drop through and pass it to simple_strntoull()
+ * and the content of *cp is irrelevant.
+ */
+ if (*cp == '-' && max_chars > 0)
+ return -simple_strntoull(cp + 1, max_chars - 1, endp, base);
+
+ return simple_strntoull(cp, max_chars, endp, base);
+}
+
/**
* simple_strtoll - convert a string to a signed long long
* @cp: The start of the string
@@ -119,10 +148,7 @@ EXPORT_SYMBOL(simple_strtol);
*/
long long simple_strtoll(const char *cp, char **endp, unsigned int base)
{
- if (*cp == '-')
- return -simple_strtoull(cp + 1, endp, base);
-
- return simple_strtoull(cp, endp, base);
+ return simple_strntoll(cp, INT_MAX, endp, base);
}
EXPORT_SYMBOL(simple_strtoll);
@@ -1834,7 +1860,8 @@ char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
struct printf_spec spec, const char *fmt)
{
bool have_t = true, have_d = true;
- bool raw = false;
+ bool raw = false, iso8601_separator = true;
+ bool found = true;
int count = 2;
if (check_pointer(&buf, end, tm, spec))
@@ -1851,14 +1878,25 @@ char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
break;
}
- raw = fmt[count] == 'r';
+ do {
+ switch (fmt[count++]) {
+ case 'r':
+ raw = true;
+ break;
+ case 's':
+ iso8601_separator = false;
+ break;
+ default:
+ found = false;
+ break;
+ }
+ } while (found);
if (have_d)
buf = date_str(buf, end, tm, raw);
if (have_d && have_t) {
- /* Respect ISO 8601 */
if (buf < end)
- *buf = 'T';
+ *buf = iso8601_separator ? 'T' : ' ';
buf++;
}
if (have_t)
@@ -2298,7 +2336,7 @@ early_param("no_hash_pointers", no_hash_pointers_enable);
* - 'd[234]' For a dentry name (optionally 2-4 last components)
* - 'D[234]' Same as 'd' but for a struct file
* - 'g' For block_device name (gendisk + partition number)
- * - 't[RT][dt][r]' For time and date as represented by:
+ * - 't[RT][dt][r][s]' For time and date as represented by:
* R struct rtc_time
* T time64_t
* - 'C' For a clock, it prints the name (Common Clock Framework) or address
@@ -3565,8 +3603,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args)
str = skip_spaces(str);
digit = *str;
- if (is_sign && digit == '-')
+ if (is_sign && digit == '-') {
+ if (field_width == 1)
+ break;
+
digit = *(str + 1);
+ }
if (!digit
|| (base == 16 && !isxdigit(digit))
@@ -3576,25 +3618,13 @@ int vsscanf(const char *buf, const char *fmt, va_list args)
break;
if (is_sign)
- val.s = qualifier != 'L' ?
- simple_strtol(str, &next, base) :
- simple_strtoll(str, &next, base);
+ val.s = simple_strntoll(str,
+ field_width >= 0 ? field_width : INT_MAX,
+ &next, base);
else
- val.u = qualifier != 'L' ?
- simple_strtoul(str, &next, base) :
- simple_strtoull(str, &next, base);
-
- if (field_width > 0 && next - str > field_width) {
- if (base == 0)
- _parse_integer_fixup_radix(str, &base);
- while (next - str > field_width) {
- if (is_sign)
- val.s = div_s64(val.s, base);
- else
- val.u = div_u64(val.u, base);
- --next;
- }
- }
+ val.u = simple_strntoull(str,
+ field_width >= 0 ? field_width : INT_MAX,
+ &next, base);
switch (qualifier) {
case 'H': /* that's 'hh' in format */