cxgb4: memory corruption in debugfs

You can't use kstrtoul() with an int or it causes memory corruption.
Also j should be unsigned or we have underflow bugs.

I considered changing "j" to unsigned long but everything fits in a u32.

Fixes: 8e3d04fd7d70 ('cxgb4: Add MPS tracing support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
index 1732e29253cd26e22d285f6ce1095281c06bd335..0a87a3247464fdd1939d8bcb5867a9f0e735cf02 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
@@ -1289,13 +1289,14 @@ static unsigned int xdigit2int(unsigned char c)
 static ssize_t mps_trc_write(struct file *file, const char __user *buf,
                             size_t count, loff_t *pos)
 {
-       int i, j, enable, ret;
+       int i, enable, ret;
        u32 *data, *mask;
        struct trace_params tp;
        const struct inode *ino;
        unsigned int trcidx;
        char *s, *p, *word, *end;
        struct adapter *adap;
+       u32 j;
 
        ino = file_inode(file);
        trcidx = (uintptr_t)ino->i_private & 3;
@@ -1340,7 +1341,7 @@ static ssize_t mps_trc_write(struct file *file, const char __user *buf,
 
                if (!strncmp(word, "qid=", 4)) {
                        end = (char *)word + 4;
-                       ret = kstrtoul(end, 10, (unsigned long *)&j);
+                       ret = kstrtouint(end, 10, &j);
                        if (ret)
                                goto out;
                        if (!adap->trace_rss) {
@@ -1369,7 +1370,7 @@ static ssize_t mps_trc_write(struct file *file, const char __user *buf,
                }
                if (!strncmp(word, "snaplen=", 8)) {
                        end = (char *)word + 8;
-                       ret = kstrtoul(end, 10, (unsigned long *)&j);
+                       ret = kstrtouint(end, 10, &j);
                        if (ret || j > 9600) {
 inval:                         count = -EINVAL;
                                goto out;
@@ -1379,7 +1380,7 @@ inval:                            count = -EINVAL;
                }
                if (!strncmp(word, "minlen=", 7)) {
                        end = (char *)word + 7;
-                       ret = kstrtoul(end, 10, (unsigned long *)&j);
+                       ret = kstrtouint(end, 10, &j);
                        if (ret || j > TFMINPKTSIZE_M)
                                goto inval;
                        tp.min_len = j;
@@ -1453,7 +1454,7 @@ inval:                            count = -EINVAL;
                }
                if (*word == '@') {
                        end = (char *)word + 1;
-                       ret = kstrtoul(end, 10, (unsigned long *)&j);
+                       ret = kstrtouint(end, 10, &j);
                        if (*end && *end != '\n')
                                goto inval;
                        if (j & 7)          /* doesn't start at multiple of 8 */