| Message ID | 1563335704-25562-1-git-send-email-wen.yang99@zte.com.cn (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Headers | show |
| Series | [v7] cpufreq/pasemi: fix an use-after-free in pas_cpufreq_cpu_init() | expand |
On 17-07-19, 11:55, Wen Yang wrote: > The cpu variable is still being used in the of_get_property() call > after the of_node_put() call, which may result in use-after-free. > > Fixes: a9acc26b75f6 ("cpufreq/pasemi: fix possible object reference leak") > Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> > Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> > Cc: Viresh Kumar <viresh.kumar@linaro.org> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: linuxppc-dev@lists.ozlabs.org > Cc: linux-pm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > --- > v7: adapt to commit ("cpufreq: Make cpufreq_generic_init() return void") > v6: keep the blank line and fix warning: label 'out_unmap_sdcpwr' defined but not used. > v5: put together the code to get, use, and release cpu device_node. > v4: restore the blank line. > v3: fix a leaked reference. > v2: clean up the code according to the advice of viresh. > > drivers/cpufreq/pasemi-cpufreq.c | 23 +++++++++-------------- > 1 file changed, 9 insertions(+), 14 deletions(-) Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/cpufreq/pasemi-cpufreq.c b/drivers/cpufreq/pasemi-cpufreq.c index 93f39a1..c66f566 100644 --- a/drivers/cpufreq/pasemi-cpufreq.c +++ b/drivers/cpufreq/pasemi-cpufreq.c @@ -131,10 +131,18 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) int err = -ENODEV; cpu = of_get_cpu_node(policy->cpu, NULL); + if (!cpu) + goto out; + max_freqp = of_get_property(cpu, "clock-frequency", NULL); of_node_put(cpu); - if (!cpu) + if (!max_freqp) { + err = -EINVAL; goto out; + } + + /* we need the freq in kHz */ + max_freq = *max_freqp / 1000; dn = of_find_compatible_node(NULL, NULL, "1682m-sdc"); if (!dn) @@ -171,16 +179,6 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) } pr_debug("init cpufreq on CPU %d\n", policy->cpu); - - max_freqp = of_get_property(cpu, "clock-frequency", NULL); - if (!max_freqp) { - err = -EINVAL; - goto out_unmap_sdcpwr; - } - - /* we need the freq in kHz */ - max_freq = *max_freqp / 1000; - pr_debug("max clock-frequency is at %u kHz\n", max_freq); pr_debug("initializing frequency table\n"); @@ -199,9 +197,6 @@ static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency()); return 0; -out_unmap_sdcpwr: - iounmap(sdcpwr_mapbase); - out_unmap_sdcasr: iounmap(sdcasr_mapbase); out:
The cpu variable is still being used in the of_get_property() call after the of_node_put() call, which may result in use-after-free. Fixes: a9acc26b75f6 ("cpufreq/pasemi: fix possible object reference leak") Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- v7: adapt to commit ("cpufreq: Make cpufreq_generic_init() return void") v6: keep the blank line and fix warning: label 'out_unmap_sdcpwr' defined but not used. v5: put together the code to get, use, and release cpu device_node. v4: restore the blank line. v3: fix a leaked reference. v2: clean up the code according to the advice of viresh. drivers/cpufreq/pasemi-cpufreq.c | 23 +++++++++-------------- 1 file changed, 9 insertions(+), 14 deletions(-)