AW: [PATCH 5.5 110/176] MIPS: VPE: Fix a double free and a memory leak in release_vpe()

From: Walter Harms
Date: Wed Mar 04 2020 - 16:38:36 EST



________________________________________
Von: kernel-janitors-owner@xxxxxxxxxxxxxxx <kernel-janitors-owner@xxxxxxxxxxxxxxx> im Auftrag von Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Gesendet: Dienstag, 3. März 2020 18:42
An: linux-kernel@xxxxxxxxxxxxxxx
Cc: Greg Kroah-Hartman; stable@xxxxxxxxxxxxxxx; Christophe JAILLET; Paul Burton; ralf@xxxxxxxxxxxxxx; linux-mips@xxxxxxxxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx
Betreff: [PATCH 5.5 110/176] MIPS: VPE: Fix a double free and a memory leak in release_vpe()

From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

commit bef8e2dfceed6daeb6ca3e8d33f9c9d43b926580 upstream.

Pointer on the memory allocated by 'alloc_progmem()' is stored in
'v->load_addr'. So this is this memory that should be freed by
'release_progmem()'.

'release_progmem()' is only a call to 'kfree()'.

With the current code, there is both a double free and a memory leak.
Fix it by passing the correct pointer to 'release_progmem()'.

Fixes: e01402b115ccc ("More AP / SP bits for the 34K, the Malta bits and things. Still wants")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Signed-off-by: Paul Burton <paulburton@xxxxxxxxxx>
Cc: ralf@xxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: kernel-janitors@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/mips/kernel/vpe.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/kernel/vpe.c
+++ b/arch/mips/kernel/vpe.c
@@ -134,7 +134,7 @@ void release_vpe(struct vpe *v)
{
list_del(&v->list);
if (v->load_addr)
- release_progmem(v);
+ release_progmem(v->load_addr);
kfree(v);
}


since release_progmem() is kfree() it is also possible to drop "if (v->load_addr)"

jm2c

re,
wh