proc mountinfo: make splice available again

Since commit 36e2c7421f02 ("fs: don't allow splice read/write without
explicit ops") we've required that file operation structures explicitly
enable splice support, rather than falling back to the default handlers.

Most /proc files use the indirect 'struct proc_ops' to describe their
file operations, and were fixed up to support splice earlier in commits
40be821d627c..b24c30c67863, but the mountinfo files interact with the
VFS directly using their own 'struct file_operations' and got missed as
a result.

This adds the necessary support for splice to work for /proc/*/mountinfo
and friends.

Reported-by: Joan Bruguera Micó <>
Reported-by: Jussi Kivilinna <>
Cc: Greg Kroah-Hartman <>
Cc: Christoph Hellwig <>
Signed-off-by: Linus Torvalds <>
1 file changed