sysctl: report EINVAL if value is larger than UINT_MAX for proc_douin…

…tvec Currently, inputting the following command will succeed but actually the value will be truncated: # echo 0x12ffffffff > /proc/sys/net/ipv4/tcp_notsent_lowat This is not friendly to the user, so instead, we should report error when the value is larger than UINT_MAX. Fixes: e7d316a ("sysctl: handle error writing UINT_MAX to u32 fields") Signed-off-by: Liping Zhang <[email protected]> Cc: Subash Abhinov Kasiviswanathan <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Eric W. Biederman <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
thomasl · Apr 8, 2017 · 425fffd · 425fffd
1 parent 8b65bb5
commit 425fffd
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
@@ -2133,6 +2133,8 @@ static int do_proc_douintvec_conv(bool *negp, unsigned long *lvalp,
 	if (write) {
 		if (*negp)
 			return -EINVAL;
+		if (*lvalp > UINT_MAX)
+			return -EINVAL;
 		*valp = *lvalp;
 	} else {
 		unsigned int val = *valp;