By using the memalloc_nofs_save() functionality, we can call
page_symlink(), safe in the knowledge that it won't recurse into the
filesystem.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
---
fs/ext4/namei.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 767b4bfe39c3..1e7c5deed5e3 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -29,6 +29,7 @@
#include <linux/pagemap.h>
#include <linux/time.h>
#include <linux/fcntl.h>
+#include <linux/sched/mm.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/quotaops.h>
@@ -3308,6 +3309,8 @@ static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
}
if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
+ unsigned int flags;
+
if (!IS_ENCRYPTED(inode))
inode->i_op = &ext4_symlink_inode_operations;
inode_nohighmem(inode);
@@ -3329,7 +3332,9 @@ static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
handle = NULL;
if (err)
goto err_drop_inode;
- err = __page_symlink(inode, disk_link.name, disk_link.len, 1);
+ flags = memalloc_nofs_save();
+ err = page_symlink(inode, disk_link.name, disk_link.len);
+ memalloc_nofs_restore(flags);
if (err)
goto err_drop_inode;
/*
--
2.34.1
