cifs: fix memory leak in smb2_copychunk_range

When using smb2_copychunk_range() for large ranges we will run through several iterations of a loop calling SMB2_ioctl() but never actually free the returned buffer except for the final iteration. This leads to memory leaks everytime a large copychunk is requested. Fixes: 9bf0c9c ("CIFS: Fix SMB2/SMB3 Copy offload support (refcopy) for large files") Cc: <[email protected]> Reviewed-by: Aurelien Aptel <[email protected]> Signed-off-by: Ronnie Sahlberg <[email protected]> Signed-off-by: Steve French <[email protected]>
jix · May 20, 2021 · d201d76 · d201d76
1 parent c0d4671
commit d201d76
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
@@ -1861,6 +1861,8 @@ smb2_copychunk_range(const unsigned int xid,
 			cpu_to_le32(min_t(u32, len, tcon->max_bytes_chunk));
 
 		/* Request server copy to target from src identified by key */
+		kfree(retbuf);
+		retbuf = NULL;
 		rc = SMB2_ioctl(xid, tcon, trgtfile->fid.persistent_fid,
 			trgtfile->fid.volatile_fid, FSCTL_SRV_COPYCHUNK_WRITE,
 			true /* is_fsctl */, (char *)pcchunk,