Tejun Heo 43d3b56b2e sysfs: make sure read buffer is zeroed ... commit f5c16f29bf upstream. 13c589d5b0 ("sysfs: use seq_file when reading regular files") switched sysfs from custom read implementation to seq_file to enable later transition to kernfs. After the change, the buffer passed to ->show() is acquired through seq_get_buf(); unfortunately, this introduces a subtle behavior change. Before the commit, the buffer passed to ->show() was always zero as it was allocated using get_zeroed_page(). Because seq_file doesn't clear buffers on allocation and neither does seq_get_buf(), after the commit, depending on the behavior of ->show(), we may end up exposing uninitialized data to userland thus possibly altering userland visible behavior and leaking information. Fix it by explicitly clearing the buffer. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Ron <ron@debian.org> Fixes: 13c589d5b0 ("sysfs: use seq_file when reading regular files") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2014-06-07 10:28:24 -07:00
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Kconfig	…
Makefile	sysfs, kernfs: move inode code to fs/kernfs/inode.c	2013-11-29 17:55:10 -08:00
dir.c	kernfs: add @mode to kernfs_create_dir[_ns]()	2013-12-17 08:59:15 -08:00
file.c	sysfs: make sure read buffer is zeroed	2014-06-07 10:28:24 -07:00
group.c	kernfs: add @mode to kernfs_create_dir[_ns]()	2013-12-17 08:59:15 -08:00
mount.c	sysfs: fix namespace refcnt leak	2014-02-25 07:37:52 -08:00
symlink.c	kernfs: s/sysfs/kernfs/ in constants	2013-12-11 17:39:20 -08:00
sysfs.h	kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly	2013-12-11 15:28:36 -08:00