diff options
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 12 | ||||
| -rw-r--r-- | arch/x86_64/lib/usercopy.c | 12 | ||||
| -rw-r--r-- | include/asm-x86_64/uaccess.h | 1 |
3 files changed, 18 insertions, 7 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index d345c71..2671fd4 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -340,7 +340,8 @@ bad: void handle_BUG(struct pt_regs *regs) { struct bug_frame f; - char tmp; + long len; + const char *prefix = ""; if (user_mode(regs)) return; @@ -350,10 +351,15 @@ void handle_BUG(struct pt_regs *regs) if (f.filename >= 0 || f.ud2[0] != 0x0f || f.ud2[1] != 0x0b) return; - if (__get_user(tmp, (char *)(long)f.filename)) + len = __strnlen_user((char *)(long)f.filename, PATH_MAX) - 1; + if (len < 0 || len >= PATH_MAX) f.filename = (int)(long)"unmapped filename"; + else if (len > 50) { + f.filename += len - 50; + prefix = "..."; + } printk("----------- [cut here ] --------- [please bite here ] ---------\n"); - printk(KERN_ALERT "Kernel BUG at %.50s:%d\n", (char *)(long)f.filename, f.line); + printk(KERN_ALERT "Kernel BUG at %s%.50s:%d\n", prefix, (char *)(long)f.filename, f.line); } #ifdef CONFIG_BUG diff --git a/arch/x86_64/lib/usercopy.c b/arch/x86_64/lib/usercopy.c index db8abba..9bc2c29 100644 --- a/arch/x86_64/lib/usercopy.c +++ b/arch/x86_64/lib/usercopy.c @@ -109,14 +109,11 @@ unsigned long clear_user(void __user *to, unsigned long n) * Return 0 on exception, a value greater than N if too long */ -long strnlen_user(const char __user *s, long n) +long __strnlen_user(const char __user *s, long n) { long res = 0; char c; - if (!access_ok(VERIFY_READ, s, n)) - return 0; - while (1) { if (res>n) return n+1; @@ -129,6 +126,13 @@ long strnlen_user(const char __user *s, long n) } } +long strnlen_user(const char __user *s, long n) +{ + if (!access_ok(VERIFY_READ, s, n)) + return 0; + return __strnlen_user(s, n); +} + long strlen_user(const char __user *s) { long res = 0; diff --git a/include/asm-x86_64/uaccess.h b/include/asm-x86_64/uaccess.h index 1bb8b8a..2892c4b 100644 --- a/include/asm-x86_64/uaccess.h +++ b/include/asm-x86_64/uaccess.h @@ -348,6 +348,7 @@ static inline int __copy_in_user(void __user *dst, const void __user *src, unsig long strncpy_from_user(char *dst, const char __user *src, long count); long __strncpy_from_user(char *dst, const char __user *src, long count); long strnlen_user(const char __user *str, long n); +long __strnlen_user(const char __user *str, long n); long strlen_user(const char __user *str); unsigned long clear_user(void __user *mem, unsigned long len); unsigned long __clear_user(void __user *mem, unsigned long len); |
