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path: root/fs/proc/proc_sysctl.c
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Diffstat (limited to 'fs/proc/proc_sysctl.c')
-rw-r--r--fs/proc/proc_sysctl.c47
1 files changed, 29 insertions, 18 deletions
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index b6f5d459b087..df2143e05c57 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -539,13 +539,13 @@ out:
return err;
}
-static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf,
+static ssize_t proc_sys_call_handler(struct file *filp, void __user *ubuf,
size_t count, loff_t *ppos, int write)
{
struct inode *inode = file_inode(filp);
struct ctl_table_header *head = grab_header(inode);
struct ctl_table *table = PROC_I(inode)->sysctl_entry;
- void *new_buf = NULL;
+ void *kbuf;
ssize_t error;
if (IS_ERR(head))
@@ -564,27 +564,38 @@ static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf,
if (!table->proc_handler)
goto out;
- error = BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, buf, &count,
- ppos, &new_buf);
+ if (write) {
+ kbuf = memdup_user_nul(ubuf, count);
+ if (IS_ERR(kbuf)) {
+ error = PTR_ERR(kbuf);
+ goto out;
+ }
+ } else {
+ error = -ENOMEM;
+ kbuf = kzalloc(count, GFP_KERNEL);
+ if (!kbuf)
+ goto out;
+ }
+
+ error = BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, &kbuf, &count,
+ ppos);
if (error)
- goto out;
+ goto out_free_buf;
/* careful: calling conventions are nasty here */
- if (new_buf) {
- mm_segment_t old_fs;
-
- old_fs = get_fs();
- set_fs(KERNEL_DS);
- error = table->proc_handler(table, write, (void __user *)new_buf,
- &count, ppos);
- set_fs(old_fs);
- kfree(new_buf);
- } else {
- error = table->proc_handler(table, write, buf, &count, ppos);
+ error = table->proc_handler(table, write, kbuf, &count, ppos);
+ if (error)
+ goto out_free_buf;
+
+ if (!write) {
+ error = -EFAULT;
+ if (copy_to_user(ubuf, kbuf, count))
+ goto out_free_buf;
}
- if (!error)
- error = count;
+ error = count;
+out_free_buf:
+ kfree(kbuf);
out:
sysctl_head_finish(head);