From 521e2bcedb8eb5d13f4c527275c81d3a0f31f2b6 Mon Sep 17 00:00:00 2001
From: dzwdz
Date: Wed, 22 Sep 2021 20:20:09 +0200
Subject: _syscall_open: strip the mount prefix in a better way

---
 src/kernel/syscalls.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c
index 16238e7..af3e0aa 100644
--- a/src/kernel/syscalls.c
+++ b/src/kernel/syscalls.c
@@ -68,12 +68,19 @@ handle_t _syscall_open(const char __user *path, int len) {
 	mount = vfs_mount_resolve(process_current->mount, path_buf, len);
 	if (!mount) goto fail;
 
+	if (mount->prefix_len > 0) { // strip prefix
+		len -= mount->prefix_len;
+		// i can't just adjust path_buf, because it needs to be passed to free()
+		// later on
+		memcpy(path_buf, path_buf + mount->prefix_len, len);
+	}
+
 	return vfs_request_create((struct vfs_request) {
 			.type = VFSOP_OPEN,
 			.input = {
 				.kern = true,
-				.buf_kern = &path_buf[mount->prefix_len], // TODO this is unfreeable
-				.len = len - mount->prefix_len,
+				.buf_kern = path_buf,
+				.len = len,
 			},
 			.caller = process_current,
 			.backend = mount->backend,
-- 
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