linux-surface/patches/4.19/0012-efivarfs-revert-fix-memory-leak-in-efivarfs_create.patch
Maximilian Luz 4703879435
Update v4.19 patches
Changes:
 - SAM:
   - Clean up code

 - Misc:
   - Revert erroneous efivarfs change in v4.19.160

Links:
 - SAM: b97b5d8f9e
 - kernel: b2de1a748f
2020-11-28 03:44:40 +01:00

38 lines
1.3 KiB
Diff

From 5818e8950d59deadd95d41d1d3747461a2e4df94 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Wed, 25 Nov 2020 08:53:03 +0100
Subject: [PATCH] efivarfs: revert "fix memory leak in efivarfs_create()"
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>
---
fs/efivarfs/super.c | 1 -
1 file changed, 1 deletion(-)
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 = {
--
2.29.2