From: Erick Archer Date: Mon, 15 Jan 2024 18:16:58 +0000 (+0100) Subject: eventfs: Use kcalloc() instead of kzalloc() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1057066009c4325bb1d8430c9274894d0860e7c3;p=linux.git eventfs: Use kcalloc() instead of kzalloc() As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, use the purpose specific kcalloc() function instead of the argument size * count in the kzalloc() function. [1] https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Link: https://lore.kernel.org/linux-trace-kernel/20240115181658.4562-1-erick.archer@gmx.com Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Mark Rutland Link: https://github.com/KSPP/linux/issues/162 Signed-off-by: Erick Archer Reviewed-by: Gustavo A. R. Silva Signed-off-by: Steven Rostedt (Google) --- diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 10580d6b50125..6795fda2af191 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -97,7 +97,7 @@ 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; }