Re: [PATCH] eventfs: Use kcalloc() instead of kzalloc()
From: Mark Rutland <mark.rutland@arm.com>
Date: 2024-01-15 10:06:32
Also in:
linux-hardening, lkml
On Sun, Jan 14, 2024 at 11:53:40AM +0100, Erick Archer wrote:
Use 2-factor multiplication argument form kcalloc() instead of kzalloc(). Link: https://github.com/KSPP/linux/issues/162 Signed-off-by: Erick Archer <redacted>
Could you put something in the commit message explaining *why* this change should be made? I assume that this is so that overflows during multiplication can be caught and handled in some way, but the commit message doesn't say that, and nor does the linked github page. The patch itself looks fine. Thanks, Mark.
quoted hunk ↗ jump to hunk
--- fs/tracefs/event_inode.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index fdff53d5a1f8..f8196289692c 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c@@ -93,7 +93,7 @@ static int eventfs_set_attr(struct mnt_idmap *idmap, struct dentry *dentry, /* Preallocate the children mode array if necessary */ if (!(dentry->d_inode->i_mode & S_IFDIR)) { if (!ei->entry_attrs) { - ei->entry_attrs = kzalloc(sizeof(*ei->entry_attrs) * ei->nr_entries, + ei->entry_attrs = kcalloc(ei->nr_entries, sizeof(*ei->entry_attrs), GFP_NOFS); if (!ei->entry_attrs) { ret = -ENOMEM;@@ -874,7 +874,7 @@ struct eventfs_inode *eventfs_create_dir(const char *name, struct eventfs_inode } if (size) { - ei->d_children = kzalloc(sizeof(*ei->d_children) * size, GFP_KERNEL); + ei->d_children = kcalloc(size, sizeof(*ei->d_children), GFP_KERNEL); if (!ei->d_children) { kfree_const(ei->name); kfree(ei);@@ -941,7 +941,7 @@ struct eventfs_inode *eventfs_create_events_dir(const char *name, struct dentry goto fail; if (size) { - ei->d_children = kzalloc(sizeof(*ei->d_children) * size, GFP_KERNEL); + ei->d_children = kcalloc(size, sizeof(*ei->d_children), GFP_KERNEL); if (!ei->d_children) goto fail; } --2.25.1