According to the investigation performed by Jacob Shivers at Red Hat,
cifs_lookup and cifs_readdir leak EAGAIN when the user session is
deleted on the server. Fix this issue by implementing a retry with
limits, as is implemented in cifs_revalidate_dentry_attr.
Signed-off-by: Thiago Rafael Becker <trbecker@xxxxxxxxx>
---
fs/cifs/dir.c | 4 ++++
fs/cifs/readdir.c | 6 ++++++
2 files changed, 10 insertions(+)
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 6bcd3e8f7cda..7c641f9a3dac 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -630,6 +630,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
struct inode *newInode = NULL;
const char *full_path;
void *page;
+ int retry_count = 0;
xid = get_xid();
@@ -673,6 +674,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
full_path, d_inode(direntry));
+again:
if (pTcon->posix_extensions)
rc = smb311_posix_get_inode_info(&newInode, full_path, parent_dir_inode->i_sb, xid);
else if (pTcon->unix_ext) {
@@ -687,6 +689,8 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
/* since paths are not looked up by component - the parent
directories are presumed to be good here */
renew_parental_timestamps(direntry);
+ } else if (rc == -EAGAIN && retry_count++ < 10) {
+ goto again;
} else if (rc == -ENOENT) {
cifs_set_time(direntry, jiffies);
newInode = NULL;
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 63bfc533c9fb..01e6d41e387f 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -844,9 +844,15 @@ static int cifs_filldir(char *find_entry, struct file *file,
struct qstr name;
int rc = 0;
ino_t ino;
+ int retry_count = 0;
+again:
rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
file_info->srch_inf.unicode);
+
+ if (rc == -EAGAIN && retry_count++ < 10)
+ goto again;
+
if (rc)
return rc;
--
2.31.1
