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Diffstat (limited to 'kernel/user_namespace.c')
-rw-r--r--kernel/user_namespace.c39
1 files changed, 19 insertions, 20 deletions
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 88fefa68c516..a965df4b54f5 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -602,9 +602,26 @@ static ssize_t map_write(struct file *file, const char __user *buf,
struct uid_gid_map new_map;
unsigned idx;
struct uid_gid_extent *extent = NULL;
- unsigned long page = 0;
+ unsigned long page;
char *kbuf, *pos, *next_line;
- ssize_t ret = -EINVAL;
+ ssize_t ret;
+
+ /* Only allow < page size writes at the beginning of the file */
+ if ((*ppos != 0) || (count >= PAGE_SIZE))
+ return -EINVAL;
+
+ /* Get a buffer */
+ page = __get_free_page(GFP_TEMPORARY);
+ kbuf = (char *) page;
+ if (!page)
+ return -ENOMEM;
+
+ /* Slurp in the user data */
+ if (copy_from_user(kbuf, buf, count)) {
+ free_page(page);
+ return -EFAULT;
+ }
+ kbuf[count] = '\0';
/*
* The userns_state_mutex serializes all writes to any given map.
@@ -638,24 +655,6 @@ static ssize_t map_write(struct file *file, const char __user *buf,
if (cap_valid(cap_setid) && !file_ns_capable(file, ns, CAP_SYS_ADMIN))
goto out;
- /* Get a buffer */
- ret = -ENOMEM;
- page = __get_free_page(GFP_TEMPORARY);
- kbuf = (char *) page;
- if (!page)
- goto out;
-
- /* Only allow < page size writes at the beginning of the file */
- ret = -EINVAL;
- if ((*ppos != 0) || (count >= PAGE_SIZE))
- goto out;
-
- /* Slurp in the user data */
- ret = -EFAULT;
- if (copy_from_user(kbuf, buf, count))
- goto out;
- kbuf[count] = '\0';
-
/* Parse the user data */
ret = -EINVAL;
pos = kbuf;