From dfef6dcd35cb4a251f6322ca9b2c06f0bb1aa1f4 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 8 Mar 2011 01:25:28 -0500 Subject: unfuck proc_sysctl ->d_compare() a) struct inode is not going to be freed under ->d_compare(); however, the thing PROC_I(inode)->sysctl points to just might. Fortunately, it's enough to make freeing that sucker delayed, provided that we don't step on its ->unregistering, clear the pointer to it in PROC_I(inode) before dropping the reference and check if it's NULL in ->d_compare(). b) I'm not sure that we *can* walk into NULL inode here (we recheck dentry->seq between verifying that it's still hashed / fetching dentry->d_inode and passing it to ->d_compare() and there's no negative hashed dentries in /proc/sys/*), but if we can walk into that, we really should not have ->d_compare() return 0 on it! Said that, I really suspect that this check can be simply killed. Nick? Signed-off-by: Al Viro --- include/linux/sysctl.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'include/linux/sysctl.h') diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 7bb5cb64f3b8..bb7c2b086fa4 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -25,6 +25,7 @@ #include #include #include +#include struct completion; @@ -1037,10 +1038,15 @@ struct ctl_table_root { struct ctl_table trees. */ struct ctl_table_header { - struct ctl_table *ctl_table; - struct list_head ctl_entry; - int used; - int count; + union { + struct { + struct ctl_table *ctl_table; + struct list_head ctl_entry; + int used; + int count; + }; + struct rcu_head rcu; + }; struct completion *unregistering; struct ctl_table *ctl_table_arg; struct ctl_table_root *root; -- cgit v1.2.3 From 684adca4f84365ca327e06dba696b62de7a79eca Mon Sep 17 00:00:00 2001 From: Stephen Rothwell Date: Thu, 10 Mar 2011 11:14:17 +1100 Subject: sysctl: the include of rcupdate.h is only needed in the kernel Fixes this build-check error: include/linux/sysctl.h:28: included file 'linux/rcupdate.h' is not exported Signed-off-by: Stephen Rothwell Signed-off-by: Linus Torvalds --- include/linux/sysctl.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sysctl.h') diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index bb7c2b086fa4..11684d9e6bd2 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -25,7 +25,6 @@ #include #include #include -#include struct completion; @@ -931,6 +930,7 @@ enum #ifdef __KERNEL__ #include +#include /* For the /proc/sys support */ struct ctl_table; -- cgit v1.2.3