fs/9p: setrlimit fix for 9p write
Current 9p client file write code does not check for RLIMIT_FSIZE resource.
This bug was found by running LTP test case for setrlimit. This bug is fixed
by calling generic_write_checks before sending the write request to the
server.
Without this patch: the write function is allowed to write above the
RLIMIT_FSIZE set by user.
With this patch: the write function checks for RLIMIT_SIZE and writes upto
the size limit.
Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index e97c92b..89c44e9 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -219,7 +219,9 @@
v9fs_file_write(struct file *filp, const char __user * data,
size_t count, loff_t * offset)
{
- int n, rsize, total = 0;
+ ssize_t retval;
+ size_t total = 0;
+ int n, rsize;
struct p9_fid *fid;
struct p9_client *clnt;
struct inode *inode = filp->f_path.dentry->d_inode;
@@ -234,6 +236,17 @@
rsize = fid->iounit ? fid->iounit : clnt->msize - P9_IOHDRSZ;
+ retval = generic_write_checks(filp, &origin, &count, 0);
+ if (retval)
+ goto out;
+
+ retval = -EINVAL;
+ if ((ssize_t) count < 0)
+ goto out;
+ retval = 0;
+ if (!count)
+ goto out;
+
do {
if (count < rsize)
rsize = count;
@@ -258,9 +271,11 @@
}
if (n < 0)
- return n;
-
- return total;
+ retval = n;
+ else
+ retval = total;
+out:
+ return retval;
}
static int v9fs_file_fsync(struct file *filp, int datasync)