The patch titled
Subject: mm/zsmalloc: do not attempt to free IS_ERR handle
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-zsmalloc-do-not-attempt-to-free-is_err-handle.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-zsmalloc-do-not-attempt-to-free-is_err-handle.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Subject: mm/zsmalloc: do not attempt to free IS_ERR handle
Date: Tue, 16 Aug 2022 14:09:06 +0900
zsmalloc() now returns ERR_PTR values as handles, which zram accidentally
can pass to zs_free(). Another bad scenario is when zcomp_compress()
fails - handle has default -ENOMEM value, and zs_free() will try to free
that "pointer value".
Add the missing check and make sure that zs_free() bails out when
ERR_PTR() is passed to it.
Link: https://lkml.kernel.org/r/20220816050906.2583956-1-senozhatsky@xxxxxxxxxxxx
Fixes: c7e6f17b52e9 ("zsmalloc: zs_malloc: return ERR_PTR on failure")
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nitin Gupta <ngupta@xxxxxxxxxx>,
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/zsmalloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/zsmalloc.c~mm-zsmalloc-do-not-attempt-to-free-is_err-handle
+++ a/mm/zsmalloc.c
@@ -1487,7 +1487,7 @@ void zs_free(struct zs_pool *pool, unsig
struct size_class *class;
enum fullness_group fullness;
- if (unlikely(!handle))
+ if (IS_ERR_OR_NULL((void *)handle))
return;
/*
_
Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are
mm-zsmalloc-do-not-attempt-to-free-is_err-handle.patch
