The patch titled
Subject: mm/damon/dbgfs: fix memory leak when using debugfs_lookup()
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-damon-dbgfs-fix-memory-leak-when-using.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-dbgfs-fix-memory-leak-when-using.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Subject: mm/damon/dbgfs: fix memory leak when using debugfs_lookup()
Date: Fri, 2 Sep 2022 19:11:49 +0000
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().
Link: https://lkml.kernel.org/r/20220902191149.112434-1-sj@xxxxxxxxxx
Fixes: 75c1c2b53c78b ("mm/damon/dbgfs: support multiple contexts")
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/damon/dbgfs.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)
--- a/mm/damon/dbgfs.c~mm-damon-dbgfs-fix-memory-leak-when-using
+++ a/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,
_
Patches currently in -mm which might be from gregkh@xxxxxxxxxxxxxxxxxxx are
mm-damon-dbgfs-fix-memory-leak-when-using.patch
