[PATCH] erofs-utils: fix resource leaks and missing returns on error paths

[Ajay Rajera]

This patch fixes two error-handling bugs in erofs-utils:

1. fuse: add missing return on getattr error
erofsfuse_getattr() calls fuse_reply_err() when erofs_read_inode_from_disk()
fails, but does not return afterwards. This causes the function to fall through
to erofsfuse_fill_stat() with uninitialized inode data and then call
fuse_reply_attr(), sending a second reply to the same FUSE request. This triggers
undefined behavior in libfuse and exposes garbage values.

2. lib: fix memory leak in erofs_gzran_builder_init error path
When inflateInit2() fails, erofs_gzran_builder_init() returns an ERR_PTR(-EFAULT)
but forgets to free the previously allocated erofs_gzran_builder struct (gb),
resulting in a memory leak.

Signed-off-by: Ajay Rajera <newajay.11r at gmail.com>
---
 fuse/main.c | 4 +++-
 lib/gzran.c | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fuse/main.c b/fuse/main.c
index 82aca8c..b634782 100644
--- a/fuse/main.c
+++ b/fuse/main.c
@@ -265,8 +265,10 @@ static void erofsfuse_getattr(fuse_req_t req, fuse_ino_t ino,
 	struct erofs_inode vi = { .sbi = &g_sbi, .nid = erofsfuse_to_nid(ino) };
 
 	ret = erofs_read_inode_from_disk(&vi);
-	if (ret < 0)
+	if (ret < 0) {
 		fuse_reply_err(req, -ret);
+		return;
+	}
 
 	erofsfuse_fill_stat(&vi, &stbuf);
 	stbuf.st_ino = ino;
diff --git a/lib/gzran.c b/lib/gzran.c
index dffb20a..8a01825 100644
--- a/lib/gzran.c
+++ b/lib/gzran.c
@@ -50,8 +50,10 @@ struct erofs_gzran_builder *erofs_gzran_builder_init(struct erofs_vfile *vf,
 	strm->avail_in = 0;
 	strm->next_in = Z_NULL;
 	ret = inflateInit2(strm, 47);	/* automatic zlib or gzip decoding */
-	if (ret != Z_OK)
+	if (ret != Z_OK) {
+		free(gb);
 		return ERR_PTR(-EFAULT);
+	}
 	gb->vf = vf;
 	gb->span_size = span_size;
 	gb->totout = gb->totin = 0;
-- 
2.51.0.windows.1