kconfig: Fix expr_free() E_NOT leak
authorUlf Magnusson <ulfalizer@gmail.com>
Sun, 8 Oct 2017 17:35:45 +0000 (19:35 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 26 Apr 2018 09:02:08 +0000 (11:02 +0200)
commit18004e6f26ec406ee762fd3f8cceaf4ab5acde41
treefb831a976dfd2ed9889788769e6a7f2918ce1d47
parent0f511f3dda8c6fb2c799eab22acfb39056047a49
kconfig: Fix expr_free() E_NOT leak

[ Upstream commit 5b1374b3b3c2fc4f63a398adfa446fb8eff791a4 ]

Only the E_NOT operand and not the E_NOT node itself was freed, due to
accidentally returning too early in expr_free(). Outline of leak:

switch (e->type) {
...
case E_NOT:
expr_free(e->left.expr);
return;
...
}
*Never reached, 'e' leaked*
free(e);

Fix by changing the 'return' to a 'break'.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

LEAK SUMMARY:
   definitely lost: 44,448 bytes in 1,852 blocks
   ...

Summary after the fix:

LEAK SUMMARY:
   definitely lost: 1,608 bytes in 67 blocks
   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scripts/kconfig/expr.c