[PATCH v2] inode: debugfs_create_dir uses mode permission from parent
From: Thomas Richter
Date: Fri Apr 27 2018 - 08:36:05 EST
Currently function debugfs_create_dir() creates a new
directory in the debugfs (usually mounted /sys/kernel/debug)
with permission rwxr-xr-x. This is hard coded.
Change this to use the parent directory permission.
Output before the patch:
root@s8360047 ~]# tree -dp -L 1 /sys/kernel/debug/
/sys/kernel/debug/
âââ [drwxr-xr-x] bdi
âââ [drwxr-xr-x] block
âââ [drwxr-xr-x] dasd
âââ [drwxr-xr-x] device_component
âââ [drwxr-xr-x] extfrag
âââ [drwxr-xr-x] hid
âââ [drwxr-xr-x] kprobes
âââ [drwxr-xr-x] kvm
âââ [drwxr-xr-x] memblock
âââ [drwxr-xr-x] pm_qos
âââ [drwxr-xr-x] qdio
âââ [drwxr-xr-x] s390
âââ [drwxr-xr-x] s390dbf
âââ [drwx------] tracing
14 directories
[root@s8360047 linux]#
Output after the patch:
[root@s8360047 ~]# tree -dp -L 1 /sys/kernel/debug/
sys/kernel/debug/
âââ [drwx------] bdi
âââ [drwx------] block
âââ [drwx------] dasd
âââ [drwx------] device_component
âââ [drwx------] extfrag
âââ [drwx------] hid
âââ [drwx------] kprobes
âââ [drwx------] kvm
âââ [drwx------] memblock
âââ [drwx------] pm_qos
âââ [drwx------] qdio
âââ [drwx------] s390
âââ [drwx------] s390dbf
âââ [drwx------] tracing
14 directories
[root@s8360047 linux]#
Here is the full diff output done with:
[root@s8360047 ~]# diff -u treefull.before treefull.after |
sed 's-^- # -' > treefull.diff
# --- treefull.before 2018-04-27 13:22:04.532824564 +0200
# +++ treefull.after 2018-04-27 13:24:12.106182062 +0200
# @@ -1,55 +1,55 @@
# /sys/kernel/debug/
# -âââ [drwxr-xr-x] bdi
# -â âââ [drwxr-xr-x] 1:0
# -â âââ [drwxr-xr-x] 1:1
# -â âââ [drwxr-xr-x] 1:10
# -â âââ [drwxr-xr-x] 1:11
# -â âââ [drwxr-xr-x] 1:12
# -â âââ [drwxr-xr-x] 1:13
# -â âââ [drwxr-xr-x] 1:14
# -â âââ [drwxr-xr-x] 1:15
# -â âââ [drwxr-xr-x] 1:2
# -â âââ [drwxr-xr-x] 1:3
# -â âââ [drwxr-xr-x] 1:4
# -â âââ [drwxr-xr-x] 1:5
# -â âââ [drwxr-xr-x] 1:6
# -â âââ [drwxr-xr-x] 1:7
# -â âââ [drwxr-xr-x] 1:8
# -â âââ [drwxr-xr-x] 1:9
# -â âââ [drwxr-xr-x] 94:0
# -âââ [drwxr-xr-x] block
# -âââ [drwxr-xr-x] dasd
# -â âââ [drwxr-xr-x] 0.0.e18a
# -â âââ [drwxr-xr-x] dasda
# -â âââ [drwxr-xr-x] global
# -âââ [drwxr-xr-x] device_component
# -âââ [drwxr-xr-x] extfrag
# -âââ [drwxr-xr-x] hid
# -âââ [drwxr-xr-x] kprobes
# -âââ [drwxr-xr-x] kvm
# -âââ [drwxr-xr-x] memblock
# -âââ [drwxr-xr-x] pm_qos
# -âââ [drwxr-xr-x] qdio
# -â âââ [drwxr-xr-x] 0.0.f5f2
# -âââ [drwxr-xr-x] s390
# -â âââ [drwxr-xr-x] stsi
# -âââ [drwxr-xr-x] s390dbf
# -â âââ [drwxr-xr-x] 0.0.e18a
# -â âââ [drwxr-xr-x] cio_crw
# -â âââ [drwxr-xr-x] cio_msg
# -â âââ [drwxr-xr-x] cio_trace
# -â âââ [drwxr-xr-x] dasd
# -â âââ [drwxr-xr-x] kvm-trace
# -â âââ [drwxr-xr-x] lgr
# -â âââ [drwxr-xr-x] qdio_0.0.f5f2
# -â âââ [drwxr-xr-x] qdio_error
# -â âââ [drwxr-xr-x] qdio_setup
# -â âââ [drwxr-xr-x] qeth_card_0.0.f5f0
# -â âââ [drwxr-xr-x] qeth_control
# -â âââ [drwxr-xr-x] qeth_msg
# -â âââ [drwxr-xr-x] qeth_setup
# -â âââ [drwxr-xr-x] vmcp
# -â âââ [drwxr-xr-x] vmur
# +âââ [drwx------] bdi
# +â âââ [drwx------] 1:0
# +â âââ [drwx------] 1:1
# +â âââ [drwx------] 1:10
# +â âââ [drwx------] 1:11
# +â âââ [drwx------] 1:12
# +â âââ [drwx------] 1:13
# +â âââ [drwx------] 1:14
# +â âââ [drwx------] 1:15
# +â âââ [drwx------] 1:2
# +â âââ [drwx------] 1:3
# +â âââ [drwx------] 1:4
# +â âââ [drwx------] 1:5
# +â âââ [drwx------] 1:6
# +â âââ [drwx------] 1:7
# +â âââ [drwx------] 1:8
# +â âââ [drwx------] 1:9
# +â âââ [drwx------] 94:0
# +âââ [drwx------] block
# +âââ [drwx------] dasd
# +â âââ [drwx------] 0.0.e18a
# +â âââ [drwx------] dasda
# +â âââ [drwx------] global
# +âââ [drwx------] device_component
# +âââ [drwx------] extfrag
# +âââ [drwx------] hid
# +âââ [drwx------] kprobes
# +âââ [drwx------] kvm
# +âââ [drwx------] memblock
# +âââ [drwx------] pm_qos
# +âââ [drwx------] qdio
# +â âââ [drwx------] 0.0.f5f2
# +âââ [drwx------] s390
# +â âââ [drwx------] stsi
# +âââ [drwx------] s390dbf
# +â âââ [drwx------] 0.0.e18a
# +â âââ [drwx------] cio_crw
# +â âââ [drwx------] cio_msg
# +â âââ [drwx------] cio_trace
# +â âââ [drwx------] dasd
# +â âââ [drwx------] kvm-trace
# +â âââ [drwx------] lgr
# +â âââ [drwx------] qdio_0.0.f5f2
# +â âââ [drwx------] qdio_error
# +â âââ [drwx------] qdio_setup
# +â âââ [drwx------] qeth_card_0.0.f5f0
# +â âââ [drwx------] qeth_control
# +â âââ [drwx------] qeth_msg
# +â âââ [drwx------] qeth_setup
# +â âââ [drwx------] vmcp
# +â âââ [drwx------] vmur
# âââ [drwx------] tracing
# âââ [drwxr-xr-x] events
# â âââ [drwxr-xr-x] alarmtimer
Fixes: edac65eaf8d5c ("debugfs: take mode-dependent parts of debugfs_get_inode() into callers")
Signed-off-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/debugfs/inode.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 13b0135..a913b12 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -512,7 +512,9 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
if (unlikely(!inode))
return failed_creating(dentry);
- inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
+ if (!parent)
+ parent = debugfs_mount->mnt_root;
+ inode->i_mode = S_IFDIR | ((d_inode(parent)->i_mode & 0770));
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
--
2.9.3