Re: [PATCH] exportfs: do not read dentry after free

2018-11-22 Thread PanBian
On Fri, Nov 23, 2018 at 07:58:15AM +0200, Amir Goldstein wrote: > On Fri, Nov 23, 2018 at 5:16 AM Pan Bian wrote: > > > > The function dentry_connected calls dput(dentry) to drop the previously > > acquired reference to dentry. In this case, dentry can be released. > > After that, IS_ROOT(dentry)

Re: [PATCH] exportfs: do not read dentry after free

2018-11-22 Thread Amir Goldstein
On Fri, Nov 23, 2018 at 5:16 AM Pan Bian wrote: > > The function dentry_connected calls dput(dentry) to drop the previously > acquired reference to dentry. In this case, dentry can be released. > After that, IS_ROOT(dentry) checks the condition > (dentry == dentry->d_parent), which may result in a

[PATCH] exportfs: do not read dentry after free

2018-11-22 Thread Pan Bian
The function dentry_connected calls dput(dentry) to drop the previously acquired reference to dentry. In this case, dentry can be released. After that, IS_ROOT(dentry) checks the condition (dentry == dentry->d_parent), which may result in a use-after-free bug. This patch directly compares dentry wi