[PATCH] kernel/kexec.c: use vscnprintf() instead of vsnprintf() in vmcoreinfo_append_str()

[PATCH] kernel/kexec.c: use vscnprintf() instead of vsnprintf() in vmcoreinfo_append_str()

[Chen Gang]

vsnprintf() may let 'r' larger than sizeof(buf), in this case, if 'r'
is also less than "vmcoreinfo_max_size - vmcoreinfo_size" (left size of
destination buffer), next memcpy() will read the unexpected addresses.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
---
 kernel/kexec.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 2a74f30..0abcd68 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1533,7 +1533,7 @@ void vmcoreinfo_append_str(const char *fmt, ...)
 	size_t r;
 
 	va_start(args, fmt);
-	r = vsnprintf(buf, sizeof(buf), fmt, args);
+	r = vscnprintf(buf, sizeof(buf), fmt, args);
 	va_end(args);
 
 	r = min(r, vmcoreinfo_max_size - vmcoreinfo_size);
-- 
1.7.7.6

[PATCH] kernel/sysctl_binary.c: use scnprintf() instead of snprintf()

[Chen Gang]

snprintf() will return the 'ideal' length which may be larger than real
buffer length, if we only want to use real length, need use scnprintf()
instead of.


Signed-off-by: Chen Gang <gang.chen@asianux.com>
---
 kernel/sysctl_binary.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index b609213..653cbbd 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -1024,7 +1024,7 @@ static ssize_t bin_intvec(struct file *file,
 			if (get_user(value, vec + i))
 				goto out_kfree;
 
-			str += snprintf(str, end - str, "%lu\t", value);
+			str += scnprintf(str, end - str, "%lu\t", value);
 		}
 
 		result = kernel_write(file, buffer, str - buffer, 0);
@@ -1095,7 +1095,7 @@ static ssize_t bin_ulongvec(struct file *file,
 			if (get_user(value, vec + i))
 				goto out_kfree;
 
-			str += snprintf(str, end - str, "%lu\t", value);
+			str += scnprintf(str, end - str, "%lu\t", value);
 		}
 
 		result = kernel_write(file, buffer, str - buffer, 0);
@@ -1205,7 +1205,7 @@ static ssize_t bin_dn_node_address(struct file *file,
 		if (get_user(dnaddr, (__le16 __user *)newval))
 			goto out;
 
-		len = snprintf(buf, sizeof(buf), "%hu.%hu",
+		len = scnprintf(buf, sizeof(buf), "%hu.%hu",
 				le16_to_cpu(dnaddr) >> 10,
 				le16_to_cpu(dnaddr) & 0x3ff);
 
-- 
1.7.7.6