Re: [syzbot] [udf?] KASAN: slab-use-after-free Read in udf_free_blocks

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Subject: [udf?] KASAN: slab-use-after-free Read in udf_free_blocks
Author: eadavis@qq.com

please test uaf in udf_free_blocks

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 123212f53f3e

diff --git a/fs/open.c b/fs/open.c
index 02dc608d40d8..bc2d1db2fcba 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -1441,11 +1441,11 @@ static long do_sys_openat2(int dfd, const char __user *filename,
 		if (IS_ERR(f)) {
 			put_unused_fd(fd);
 			fd = PTR_ERR(f);
+			putname(tmp);
 		} else {
 			fd_install(fd, f);
 		}
 	}
-	putname(tmp);
 	return fd;
 }