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+From e3a4b0234c813584d5bca2d9731b20a8e325e6d9 Mon Sep 17 00:00:00 2001
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+From: Ard Biesheuvel <ardb@kernel.org>
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+Date: Wed, 25 Nov 2020 08:53:03 +0100
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+Subject: [PATCH] efivarfs: revert "fix memory leak in efivarfs_create()"
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+
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+The memory leak addressed by commit fe5186cf12e3 is a false positive:
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+all allocations are recorded in a linked list, and freed when the
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+filesystem is unmounted. This leads to double frees, and as reported
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+by David, leads to crashes if SLUB is configured to self destruct when
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+double frees occur.
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+
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+So drop the redundant kfree() again, and instead, mark the offending
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+pointer variable so the allocation is ignored by kmemleak.
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+
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+Cc: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
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+Fixes: fe5186cf12e3 ("efivarfs: fix memory leak in efivarfs_create()")
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+Reported-by: David Laight <David.Laight@aculab.com>
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+Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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+---
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+ fs/efivarfs/inode.c | 1 +
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+ fs/efivarfs/super.c | 1 -
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+ 2 files changed, 1 insertion(+), 1 deletion(-)
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+
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+diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c
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+index 96c0c86f3fff..38324427a2b3 100644
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+--- a/fs/efivarfs/inode.c
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++++ b/fs/efivarfs/inode.c
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+@@ -103,6 +103,7 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry,
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+ var->var.VariableName[i] = '\0';
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+
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+ inode->i_private = var;
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++ kmemleak_ignore(var);
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+
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+ err = efivar_entry_add(var, &efivarfs_list);
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+ if (err)
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+diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c
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+index f943fd0b0699..15880a68faad 100644
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+--- a/fs/efivarfs/super.c
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++++ b/fs/efivarfs/super.c
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+@@ -21,7 +21,6 @@ LIST_HEAD(efivarfs_list);
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+ static void efivarfs_evict_inode(struct inode *inode)
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+ {
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+ clear_inode(inode);
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+- kfree(inode->i_private);
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+ }
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+
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+ static const struct super_operations efivarfs_ops = {
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+--
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+2.29.2
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+
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