From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit c915ef890d5dc79f483e1ca3b3a5b5f1a170690c ]
If the user passes a "level" value which is higher than 31 then that leads to shift wrapping. The undefined behavior will lead to a syzkaller stack dump.
Fixes: 5632708f4452 ("drm/amd/powerplay: add dpm force multiple levels on cz/tonga/fiji/polaris (v2)") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/pm/amdgpu_pm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/pm/amdgpu_pm.c b/drivers/gpu/drm/amd/pm/amdgpu_pm.c index 529816637c731..9f383b9041d28 100644 --- a/drivers/gpu/drm/amd/pm/amdgpu_pm.c +++ b/drivers/gpu/drm/amd/pm/amdgpu_pm.c @@ -1070,7 +1070,7 @@ static ssize_t amdgpu_get_pp_dpm_sclk(struct device *dev, static ssize_t amdgpu_read_mask(const char *buf, size_t count, uint32_t *mask) { int ret; - long level; + unsigned long level; char *sub_str = NULL; char *tmp; char buf_cpy[AMDGPU_MASK_BUF_MAX + 1]; @@ -1086,8 +1086,8 @@ static ssize_t amdgpu_read_mask(const char *buf, size_t count, uint32_t *mask) while (tmp[0]) { sub_str = strsep(&tmp, delimiter); if (strlen(sub_str)) { - ret = kstrtol(sub_str, 0, &level); - if (ret) + ret = kstrtoul(sub_str, 0, &level); + if (ret || level > 31) return -EINVAL; *mask |= 1 << level; } else