ext4: fix possible use-after-free in ext4_remove_li_request()
ext4: fix possible use-after-free in ext4_remove_li_request()

We need to take reference to the s_li_request after we take a mutex,
because it might be freed since then, hence result in accessing old
already freed memory. Also we should protect the whole
ext4_remove_li_request() because ext4_li_info might be in the process of
being freed in ext4_lazyinit_thread().

Signed-off-by: Lukas Czerner <6c9141d0e2318b390a8a6bf8ecd9f819d16f05b4@redhat.com>
Signed-off-by: "Theodore Ts'o" <4ed386e0495d3e109932df055831d9ec2f824927@mit.edu>
Reviewed-by: Eric Sandeen <d55521028c14e0f378be5444e4ea388161c0d7e7@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs