On 12/14/2018 11:56 AM, Nicholas Mc Guire wrote: > kzalloc() return should always be checked - notably in example code > where this may be seen as reference. On failure of allocation in > livepatch_fix1_dummy_alloc() respectively dummy_alloc() previous > allocation is freed (thanks to Petr Mladek <[email protected]> for > catching this) and NULL returned. > > Signed-off-by: Nicholas Mc Guire <[email protected]> > Fixes: 439e7271dc2b ("livepatch: introduce shadow variable API") > --- > > Problem located with an experimental coccinelle script > > Patch was compile tested with: x86_64_defconfig + FTRACE=y > FUNCTION_TRACER=y, EXPERT=y, LATENCYTOP=y, SAMPLES=y, > SAMPLE_LIVEPATCH=y > > Patch is against 4.20-rc6 (localversion-next is next-20181214) > on top of 0001-livepatch-fix-non-static-warnings.patch > > samples/livepatch/livepatch-shadow-fix1.c | 5 +++++ > samples/livepatch/livepatch-shadow-mod.c | 4 ++++ > 2 files changed, 9 insertions(+) > > diff --git a/samples/livepatch/livepatch-shadow-fix1.c > b/samples/livepatch/livepatch-shadow-fix1.c > index eaab10f..1974eb5 100644 > --- a/samples/livepatch/livepatch-shadow-fix1.c > +++ b/samples/livepatch/livepatch-shadow-fix1.c > @@ -89,6 +89,11 @@ static __noclone struct dummy > *livepatch_fix1_dummy_alloc(void) > * pointer to handle resource release. > */ > leak = kzalloc(sizeof(int), GFP_KERNEL); > + if (!leak) { > + kfree(d); > + return NULL; > + } > + > klp_shadow_alloc(d, SV_LEAK, sizeof(leak), GFP_KERNEL, > shadow_leak_ctor, leak); > > diff --git a/samples/livepatch/livepatch-shadow-mod.c > b/samples/livepatch/livepatch-shadow-mod.c > index dc69da0..b4ece36 100644 > --- a/samples/livepatch/livepatch-shadow-mod.c > +++ b/samples/livepatch/livepatch-shadow-mod.c > @@ -123,6 +123,10 @@ static __noclone noinline struct dummy *dummy_alloc(void) > > /* Oops, forgot to save leak! */ > leak = kzalloc(sizeof(int), GFP_KERNEL); > + if (!leak) { > + kfree(d); > + return NULL; > + } > > pr_info("%s: dummy @ %p, expires @ %lx\n", > __func__, d, d->jiffies_expire); >
Patch v2 2/2 looks good, thanks for combining. Acked-by: Joe Lawrence <[email protected]> -- Joe
