diff options
| author | Sivan Zohar-Kotzer <sivany32@gmail.com> | 2025-07-02 01:13:55 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-15 12:13:36 +0200 |
| commit | 8374ac7d69a57d737e701a851ffe980a0d27d3ad (patch) | |
| tree | 84ac8806911aa56525ee363c6e3436d1c8d0600d | |
| parent | 3e3ebf358cda26135075b9754a78b6a89a0ae846 (diff) | |
powercap: dtpm_cpu: Fix NULL pointer dereference in get_pd_power_uw()
[ Upstream commit 46dc57406887dd02565cb264224194a6776d882b ]
The get_pd_power_uw() function can crash with a NULL pointer dereference
when em_cpu_get() returns NULL. This occurs when a CPU becomes impossible
during runtime, causing get_cpu_device() to return NULL, which propagates
through em_cpu_get() and leads to a crash when em_span_cpus() dereferences
the NULL pointer.
Add a NULL check after em_cpu_get() and return 0 if unavailable,
matching the existing fallback behavior in __dtpm_cpu_setup().
Fixes: eb82bace8931 ("powercap/drivers/dtpm: Scale the power with the load")
Signed-off-by: Sivan Zohar-Kotzer <sivany32@gmail.com>
Link: https://patch.msgid.link/20250701221355.96916-1-sivany32@gmail.com
[ rjw: Drop an excess empty code line ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/powercap/dtpm_cpu.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c index 6b6f51b21550..99390ec1481f 100644 --- a/drivers/powercap/dtpm_cpu.c +++ b/drivers/powercap/dtpm_cpu.c @@ -96,6 +96,8 @@ static u64 get_pd_power_uw(struct dtpm *dtpm) int i; pd = em_cpu_get(dtpm_cpu->cpu); + if (!pd) + return 0; pd_mask = em_span_cpus(pd); |