From 911bf86238bb54f16c10790e82fa1d2610f4648d Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 25 Nov 2020 08:45:55 +0100 Subject: [PATCH] efivarfs: revert "fix memory leak in efivarfs_create()" [ Upstream commit ff04f3b6f2e27f8ae28a498416af2a8dd5072b43 ] The memory leak addressed by commit fe5186cf12e3 is a false positive: all allocations are recorded in a linked list, and freed when the filesystem is unmounted. This leads to double frees, and as reported by David, leads to crashes if SLUB is configured to self destruct when double frees occur. So drop the redundant kfree() again, and instead, mark the offending pointer variable so the allocation is ignored by kmemleak. Cc: Vamshi K Sthambamkadi Fixes: fe5186cf12e3 ("efivarfs: fix memory leak in efivarfs_create()") Reported-by: David Laight Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin --- fs/efivarfs/inode.c | 2 ++ fs/efivarfs/super.c | 1 - 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c index 71fccccf317e..5decb3e06563 100644 --- a/fs/efivarfs/inode.c +++ b/fs/efivarfs/inode.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -104,6 +105,7 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry, var->var.VariableName[i] = '\0'; inode->i_private = var; + kmemleak_ignore(var); err = efivar_entry_add(var, &efivarfs_list); if (err) diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index bbf056191aaa..b1e6acec5304 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -23,7 +23,6 @@ LIST_HEAD(efivarfs_list); static void efivarfs_evict_inode(struct inode *inode) { clear_inode(inode); - kfree(inode->i_private); } static const struct super_operations efivarfs_ops = {