[PATCH 5.15 014/110] mISDN: Fix memory leak in dsp_pipeline_build()

Greg Kroah-Hartman
2022-03-14T12:16:04Z

From: Alexey Khoroshilov <khoroshilov@ispras.ru>

[ Upstream commit c6a502c2299941c8326d029cfc8a3bc8a4607ad5 ]

dsp_pipeline_build() allocates dup pointer by kstrdup(cfg),
but then it updates dup variable by strsep(&dup, "|").
As a result when it calls kfree(dup), the dup variable contains NULL.

Found by Linux Driver Verification project (linuxtesting.org) with SVACE.

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Fixes: 960366cf8dbb ("Add mISDN DSP")
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/isdn/mISDN/dsp_pipeline.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/isdn/mISDN/dsp_pipeline.c b/drivers/isdn/mISDN/dsp_pipeline.c
index e11ca6bbc7f4..c3b2c99b5cd5 100644
--- a/drivers/isdn/mISDN/dsp_pipeline.c
+++ b/drivers/isdn/mISDN/dsp_pipeline.c
@@ -192,7 +192,7 @@ void dsp_pipeline_destroy(struct dsp_pipeline *pipeline)
int dsp_pipeline_build(struct dsp_pipeline *pipeline, const char *cfg)
{
int found = 0;
- char *dup, *tok, *name, *args;
+ char *dup, *next, *tok, *name, *args;
struct dsp_element_entry *entry, *n;
struct dsp_pipeline_entry *pipeline_entry;
struct mISDN_dsp_element *elem;
@@ -203,10 +203,10 @@ int dsp_pipeline_build(struct dsp_pipeline *pipeline, const char *cfg)
if (!list_empty(&pipeline->list))
_dsp_pipeline_destroy(pipeline);

- dup = kstrdup(cfg, GFP_ATOMIC);
+ dup = next = kstrdup(cfg, GFP_ATOMIC);
if (!dup)
return 0;
- while ((tok = strsep(&dup, "|"))) {
+ while ((tok = strsep(&next, "|"))) {
if (!strlen(tok))
continue;
name = strsep(&tok, "(");
--
2.34.1