On Tue, 31 May 2011, Lukas Czerner wrote: > 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 <[email protected]> > Reviewed-by: Eric Sandeen <[email protected]> > --- > fs/ext4/super.c | 10 ++++++---- > 1 files changed, 6 insertions(+), 4 deletions(-) > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index fd51a4a..ed5e80e 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -2735,14 +2735,16 @@ static void ext4_remove_li_request(struct > ext4_li_request *elr) > > static void ext4_unregister_li_request(struct super_block *sb) > { > - struct ext4_li_request *elr = EXT4_SB(sb)->s_li_request; > - > - if (!ext4_li_info) > + mutex_lock(&ext4_li_mtx); > + if (!ext4_li_info) { > + mutex_unlock(&ext4_li_mtx); > return; > + } > > mutex_lock(&ext4_li_info->li_list_mtx); > - ext4_remove_li_request(elr); > + ext4_remove_li_request(EXT4_SB(sb)->s_li_request); > mutex_unlock(&ext4_li_info->li_list_mtx); > + mutex_unlock(&ext4_li_mtx); > } > > static struct task_struct *ext4_lazyinit_task; >
This is upstream commit 1bb933fb1fa8e4cb337a0d5dfd2ff4c0dc2073e8 _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
