Commit e9c8da67 authored by Amir Goldstein's avatar Amir Goldstein Committed by Miklos Szeredi
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fuse: do not allow mapping a non-regular backing file 



We do not support passthrough operations other than read/write on
regular file, so allowing non-regular backing files makes no sense.

Fixes: efad7153 ("fuse: allow O_PATH fd for FUSE_DEV_IOC_BACKING_OPEN")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Reviewed-by: default avatarBernd Schubert <bschubert@ddn.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 1b237f19

fs/fuse/passthrough.c

+5 −0
Original line number Diff line number Diff line
@@ -237,6 +237,11 @@ int fuse_backing_open(struct fuse_conn *fc, struct fuse_backing_map *map) 
	if (!file)

		goto out;



	/* read/write/splice/mmap passthrough only relevant for regular files */

	res = d_is_dir(file->f_path.dentry) ? -EISDIR : -EINVAL;

	if (!d_is_reg(file->f_path.dentry))

		goto out_fput;



	backing_sb = file_inode(file)->i_sb;

	res = -ELOOP;

	if (backing_sb->s_stack_depth >= fc->max_stack_depth)