Hi Greg, I am not sure this patch should be backported to 3.0. The logic there seems to be different. My patch is on top of some code reorg that happened in 3.4 (076c3eed2c31). If you checked that the patch is also ok in 3.0 go ahead, but I am not sure one way or the other. The patch is good for 3.4 and later.
Thanks, Francesco On Fri, Sep 21, 2012 at 10:57 AM, <[email protected]> wrote: > > > This is a note to let you know that I've just added the patch titled > > fs/proc: fix potential unregister_sysctl_table hang > > to the 3.0-stable tree which can be found at: > > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary > > The filename of the patch is: > fs-proc-fix-potential-unregister_sysctl_table-hang.patch > and it can be found in the queue-3.0 subdirectory. > > If you, or anyone else, feels it should not be added to the stable tree, > please let <[email protected]> know about it. > > > From 6bf6104573482570f7103d3e5ddf9574db43a363 Mon Sep 17 00:00:00 2001 > From: Francesco Ruggeri <[email protected]> > Date: Thu, 13 Sep 2012 15:03:37 -0700 > Subject: fs/proc: fix potential unregister_sysctl_table hang > > From: Francesco Ruggeri <[email protected]> > > commit 6bf6104573482570f7103d3e5ddf9574db43a363 upstream. > > The unregister_sysctl_table() function hangs if all references to its > ctl_table_header structure are not dropped. > > This can happen sometimes because of a leak in proc_sys_lookup(): > proc_sys_lookup() gets a reference to the table via lookup_entry(), but > it does not release it when a subsequent call to sysctl_follow_link() > fails. > > This patch fixes this leak by making sure the reference is always > dropped on return. > > See also commit 076c3eed2c31 ("sysctl: Rewrite proc_sys_lookup > introducing find_entry and lookup_entry") which reorganized this code in > 3.4. > > Tested in Linux 3.4.4. > > Signed-off-by: Francesco Ruggeri <[email protected]> > Signed-off-by: Linus Torvalds <[email protected]> > Signed-off-by: Greg Kroah-Hartman <[email protected]> > > --- > fs/proc/proc_sysctl.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > --- a/fs/proc/proc_sysctl.c > +++ b/fs/proc/proc_sysctl.c > @@ -113,9 +113,6 @@ static struct dentry *proc_sys_lookup(st > > err = ERR_PTR(-ENOMEM); > inode = proc_sys_make_inode(dir->i_sb, h ? h : head, p); > - if (h) > - sysctl_head_finish(h); > - > if (!inode) > goto out; > > @@ -124,6 +121,8 @@ static struct dentry *proc_sys_lookup(st > d_add(dentry, inode); > > out: > + if (h) > + sysctl_head_finish(h); > sysctl_head_finish(head); > return err; > } > > > Patches currently in stable-queue which might be from > [email protected] are > > queue-3.0/fs-proc-fix-potential-unregister_sysctl_table-hang.patch > > queue-3.0/net-ipv4-ipmr_expire_timer-causes-crash-when-removing-net-namespace.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
