From: Ard Biesheuvel ardb@kernel.org
[ 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 vamshi.k.sthambamkadi@gmail.com Fixes: fe5186cf12e3 ("efivarfs: fix memory leak in efivarfs_create()") Reported-by: David Laight David.Laight@aculab.com Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 8c6ab6c95727..7f40343b39b0 100644 --- a/fs/efivarfs/inode.c +++ b/fs/efivarfs/inode.c @@ -10,6 +10,7 @@ #include <linux/efi.h> #include <linux/fs.h> #include <linux/ctype.h> +#include <linux/kmemleak.h> #include <linux/slab.h> #include <linux/uuid.h>
@@ -106,6 +107,7 @@ 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 7808a26bd33f..834615f13f3e 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 = {