| Message ID | 1433364818-6682-1-git-send-email-sboyd@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Stephen, On Wed, Jun 03, 2015 at 09:53:37PM +0100, Stephen Boyd wrote: > It's possible, albeit unlikely, that using the of_node here will > reference freed memory. Call of_node_put() after printing the > name to be safe. > > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > --- > arch/arm64/kernel/perf_event.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c > index 702591f6180a..8af7784a8e35 100644 > --- a/arch/arm64/kernel/perf_event.c > +++ b/arch/arm64/kernel/perf_event.c > @@ -1340,12 +1340,13 @@ static int armpmu_device_probe(struct platform_device *pdev) > if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL)) > break; > > - of_node_put(dn); > if (cpu >= nr_cpu_ids) { > pr_warn("Failed to find logical CPU for %s\n", > dn->name); > + of_node_put(dn); > break; > } > + of_node_put(dn); > > irqs[i] = cpu; > } Yeah, I agree this needs changing but given (a) the CPU node isn't going to disappear and (b) this patch will conflict horribly with my queue for 4.2, do you mind if I sit on this until after the merge window (as a fix for 4.2)? Will
On 06/05/2015 07:45 AM, Will Deacon wrote: > On Wed, Jun 03, 2015 at 09:53:37PM +0100, Stephen Boyd wrote: >> arch/arm64/kernel/perf_event.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c >> index 702591f6180a..8af7784a8e35 100644 >> --- a/arch/arm64/kernel/perf_event.c >> +++ b/arch/arm64/kernel/perf_event.c >> @@ -1340,12 +1340,13 @@ static int armpmu_device_probe(struct platform_device *pdev) >> if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL)) >> break; >> >> - of_node_put(dn); >> if (cpu >= nr_cpu_ids) { >> pr_warn("Failed to find logical CPU for %s\n", >> dn->name); >> + of_node_put(dn); >> break; >> } >> + of_node_put(dn); >> >> irqs[i] = cpu; >> } > Yeah, I agree this needs changing but given (a) the CPU node isn't going > to disappear and (b) this patch will conflict horribly with my queue for > 4.2, do you mind if I sit on this until after the merge window (as a fix > for 4.2)? > > Sure, no problem.
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index 702591f6180a..8af7784a8e35 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -1340,12 +1340,13 @@ static int armpmu_device_probe(struct platform_device *pdev) if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL)) break; - of_node_put(dn); if (cpu >= nr_cpu_ids) { pr_warn("Failed to find logical CPU for %s\n", dn->name); + of_node_put(dn); break; } + of_node_put(dn); irqs[i] = cpu; }
It's possible, albeit unlikely, that using the of_node here will reference freed memory. Call of_node_put() after printing the name to be safe. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> --- arch/arm64/kernel/perf_event.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)