diff options
Diffstat (limited to 'lib/string_helpers.c')
-rw-r--r-- | lib/string_helpers.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 5c88204b6..ecaac2c05 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -10,6 +10,10 @@ #include <linux/export.h> #include <linux/ctype.h> #include <linux/errno.h> +#include <linux/fs.h> +#include <linux/limits.h> +#include <linux/mm.h> +#include <linux/slab.h> #include <linux/string.h> #include <linux/string_helpers.h> @@ -534,3 +538,91 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, return p - dst; } EXPORT_SYMBOL(string_escape_mem); + +/* + * Return an allocated string that has been escaped of special characters + * and double quotes, making it safe to log in quotes. + */ +char *kstrdup_quotable(const char *src, gfp_t gfp) +{ + size_t slen, dlen; + char *dst; + const int flags = ESCAPE_HEX; + const char esc[] = "\f\n\r\t\v\a\e\\\""; + + if (!src) + return NULL; + slen = strlen(src); + + dlen = string_escape_mem(src, slen, NULL, 0, flags, esc); + dst = kmalloc(dlen + 1, gfp); + if (!dst) + return NULL; + + WARN_ON(string_escape_mem(src, slen, dst, dlen, flags, esc) != dlen); + dst[dlen] = '\0'; + + return dst; +} +EXPORT_SYMBOL_GPL(kstrdup_quotable); + +/* + * Returns allocated NULL-terminated string containing process + * command line, with inter-argument NULLs replaced with spaces, + * and other special characters escaped. + */ +char *kstrdup_quotable_cmdline(struct task_struct *task, gfp_t gfp) +{ + char *buffer, *quoted; + int i, res; + + buffer = kmalloc(PAGE_SIZE, GFP_TEMPORARY); + if (!buffer) + return NULL; + + res = get_cmdline(task, buffer, PAGE_SIZE - 1); + buffer[res] = '\0'; + + /* Collapse trailing NULLs, leave res pointing to last non-NULL. */ + while (--res >= 0 && buffer[res] == '\0') + ; + + /* Replace inter-argument NULLs. */ + for (i = 0; i <= res; i++) + if (buffer[i] == '\0') + buffer[i] = ' '; + + /* Make sure result is printable. */ + quoted = kstrdup_quotable(buffer, gfp); + kfree(buffer); + return quoted; +} +EXPORT_SYMBOL_GPL(kstrdup_quotable_cmdline); + +/* + * Returns allocated NULL-terminated string containing pathname, + * with special characters escaped, able to be safely logged. If + * there is an error, the leading character will be "<". + */ +char *kstrdup_quotable_file(struct file *file, gfp_t gfp) +{ + char *temp, *pathname; + + if (!file) + return kstrdup("<unknown>", gfp); + + /* We add 11 spaces for ' (deleted)' to be appended */ + temp = kmalloc(PATH_MAX + 11, GFP_TEMPORARY); + if (!temp) + return kstrdup("<no_memory>", gfp); + + pathname = file_path(file, temp, PATH_MAX + 11); + if (IS_ERR(pathname)) + pathname = kstrdup("<too_long>", gfp); + else + pathname = kstrdup_quotable(pathname, gfp); + + kfree(temp); + return pathname; +} +EXPORT_SYMBOL_GPL(kstrdup_quotable_file); |