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Subject[PATCH v2] livepatch: Reorder to use before freeing a pointer
Date
From: Tom Rix <trix@redhat.com>

Clang static analysis reports this issue
livepatch-shadow-fix1.c:113:2: warning: Use of
memory after it is freed
pr_info("%s: dummy @ %p, prevented leak @ %p\n",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The pointer is freed in the previous statement.
Reorder the pr_info to report before the free.

Similar issue in livepatch-shadow-fix2.c

Signed-off-by: Tom Rix <trix@redhat.com>
---
v2: Fix similar issue in livepatch-shadow-fix2.c

samples/livepatch/livepatch-shadow-fix1.c | 2 +-
samples/livepatch/livepatch-shadow-fix2.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c
index 918ce17b43fda..6701641bf12d4 100644
--- a/samples/livepatch/livepatch-shadow-fix1.c
+++ b/samples/livepatch/livepatch-shadow-fix1.c
@@ -109,9 +109,9 @@ static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data)
void *d = obj;
int **shadow_leak = shadow_data;

- kfree(*shadow_leak);
pr_info("%s: dummy @ %p, prevented leak @ %p\n",
__func__, d, *shadow_leak);
+ kfree(*shadow_leak);
}

static void livepatch_fix1_dummy_free(struct dummy *d)
diff --git a/samples/livepatch/livepatch-shadow-fix2.c b/samples/livepatch/livepatch-shadow-fix2.c
index 29fe5cd420472..361046a4f10cf 100644
--- a/samples/livepatch/livepatch-shadow-fix2.c
+++ b/samples/livepatch/livepatch-shadow-fix2.c
@@ -61,9 +61,9 @@ static void livepatch_fix2_dummy_leak_dtor(void *obj, void *shadow_data)
void *d = obj;
int **shadow_leak = shadow_data;

- kfree(*shadow_leak);
pr_info("%s: dummy @ %p, prevented leak @ %p\n",
__func__, d, *shadow_leak);
+ kfree(*shadow_leak);
}

static void livepatch_fix2_dummy_free(struct dummy *d)
--
2.26.3
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