diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mtrr/if.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/if.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c index 08b6ea4c62b4..3c1b12d461d1 100644 --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -96,17 +96,24 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) unsigned long long base, size; char *ptr; char line[LINE_SIZE]; + int length; size_t linelen; if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (!len) - return -EINVAL; memset(line, 0, LINE_SIZE); - if (len > LINE_SIZE) - len = LINE_SIZE; - if (copy_from_user(line, buf, len - 1)) + + length = len; + length--; + + if (length > LINE_SIZE - 1) + length = LINE_SIZE - 1; + + if (length < 0) + return -EINVAL; + + if (copy_from_user(line, buf, length)) return -EFAULT; linelen = strlen(line); @@ -126,8 +133,8 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) return -EINVAL; base = simple_strtoull(line + 5, &ptr, 0); - for (; isspace(*ptr); ++ptr) - ; + while (isspace(*ptr)) + ptr++; if (strncmp(ptr, "size=", 5)) return -EINVAL; @@ -135,14 +142,14 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) size = simple_strtoull(ptr + 5, &ptr, 0); if ((base & 0xfff) || (size & 0xfff)) return -EINVAL; - for (; isspace(*ptr); ++ptr) - ; + while (isspace(*ptr)) + ptr++; if (strncmp(ptr, "type=", 5)) return -EINVAL; ptr += 5; - for (; isspace(*ptr); ++ptr) - ; + while (isspace(*ptr)) + ptr++; for (i = 0; i < MTRR_NUM_TYPES; ++i) { if (strcmp(ptr, mtrr_strings[i])) |