+ zram-correctly-handle-all-next_arg-cases.patch added to mm-unstable branch

+ zram-correctly-handle-all-next_arg-cases.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: zram: correctly handle all next_arg() cases
has been added to the -mm mm-unstable branch.  Its filename is
     zram-correctly-handle-all-next_arg-cases.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zram-correctly-handle-all-next_arg-cases.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@chromium.org>
Subject: zram: correctly handle all next_arg() cases
Date: Tue, 3 Jan 2023 12:01:19 +0900

When supplied buffer does not have assignment sign next_arg() sets `val`
pointer to NULL, so we cannot dereference it.  Add a NULL pointer test to
handle `param` case, in addition to `*val` test, which handles cases when
param has no value assigned to it: `param=`.

Link: https://lkml.kernel.org/r/20230103030119.1496358-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/block/zram/zram_drv.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/block/zram/zram_drv.c~zram-correctly-handle-all-next_arg-cases
+++ a/drivers/block/zram/zram_drv.c
@@ -1140,7 +1140,7 @@ static ssize_t recomp_algorithm_store(st
 	while (*args) {
 		args = next_arg(args, &param, &val);
 
-		if (!*val)
+		if (!val || !*val)
 			return -EINVAL;
 
 		if (!strcmp(param, "algo")) {
@@ -1824,7 +1824,7 @@ static ssize_t recompress_store(struct d
 	while (*args) {
 		args = next_arg(args, &param, &val);
 
-		if (!*val)
+		if (!val || !*val)
 			return -EINVAL;
 
 		if (!strcmp(param, "type")) {
_

Patches currently in -mm which might be from senozhatsky@chromium.org are

zram-correctly-handle-all-next_arg-cases.patch