| Message ID | 20220902191149.112434-1-sj@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] mm/damon/dbgfs: fix memory leak when using | expand |
On Fri, Sep 02, 2022 at 07:11:49PM +0000, SeongJae Park wrote: > From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > debugfs_lookup() > Date: Fri, 2 Sep 2022 14:56:31 +0200 [thread overview] > Message-ID: <20220902125631.128329-1-gregkh@linuxfoundation.org> (raw) > > When calling debugfs_lookup() the result must have dput() called on it, > otherwise the memory will leak over time. Fix this up by properly > calling dput(). > > Fixes: 75c1c2b53c78b ("mm/damon/dbgfs: support multiple contexts") > Cc: <stable@vger.kernel.org> # 5.15.x > Cc: SeongJae Park <sj@kernel.org> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: damon@lists.linux.dev > Cc: linux-mm@kvack.org > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Signed-off-by: Andrew Morton <akpm@linux-foundation.org> > Signed-off-by: SeongJae Park <sj@kernel.org> > --- > Changes from v1 > (https://lore.kernel.org/damon/20220902125631.128329-1-gregkh@linuxfoundation.org/) > - Call dput() for failure-return case (Andrew Morton) Thanks for fixing this up, I missed the other return error cases in my rush to audit the whole tree at once. This version looks great, and I see Andrew has taken it now into his tree, thanks! greg k-h
diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 3b55a1b219b5..652a94deafe3 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -884,6 +884,7 @@ static int dbgfs_rm_context(char *name) struct dentry *root, *dir, **new_dirs; struct damon_ctx **new_ctxs; int i, j; + int ret = 0; if (damon_nr_running_ctxs()) return -EBUSY; @@ -898,14 +899,16 @@ static int dbgfs_rm_context(char *name) new_dirs = kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_dirs), GFP_KERNEL); - if (!new_dirs) - return -ENOMEM; + if (!new_dirs) { + ret = -ENOMEM; + goto out_dput; + } new_ctxs = kmalloc_array(dbgfs_nr_ctxs - 1, sizeof(*dbgfs_ctxs), GFP_KERNEL); if (!new_ctxs) { - kfree(new_dirs); - return -ENOMEM; + ret = -ENOMEM; + goto out_new_dirs; } for (i = 0, j = 0; i < dbgfs_nr_ctxs; i++) { @@ -925,7 +928,13 @@ static int dbgfs_rm_context(char *name) dbgfs_ctxs = new_ctxs; dbgfs_nr_ctxs--; - return 0; + goto out_dput; + +out_new_dirs: + kfree(new_dirs); +out_dput: + dput(dir); + return ret; } static ssize_t dbgfs_rm_context_write(struct file *file,