In nvkm_acr_hsfw_load_bl(), the return value of kmalloc() is directly passed to memcpy(), which could lead to undefined behavior on failure of kmalloc().
Fix this bug by using kmemdup() instead of kmalloc()+memcpy().
This bug was found by a static analyzer.
Builds with 'make allyesconfig' show no new warnings, and our static analyzer no longer warns about this code.
Fixes: 22dcda45a3d1 ("drm/nouveau/acr: implement new subdev to replace "secure boot"") Signed-off-by: Zhou Qingyang zhou1615@umn.edu --- The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug.
drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c b/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c index 667fa016496e..a6ea89a5d51a 100644 --- a/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/acr/hsfw.c @@ -142,11 +142,12 @@ nvkm_acr_hsfw_load_bl(struct nvkm_acr *acr, const char *name, int ver,
hsfw->imem_size = desc->code_size; hsfw->imem_tag = desc->start_tag; - hsfw->imem = kmalloc(desc->code_size, GFP_KERNEL); - memcpy(hsfw->imem, data + desc->code_off, desc->code_size); - + hsfw->imem = kmemdup(data + desc->code_off, desc->code_size, GFP_KERNEL); nvkm_firmware_put(fw); - return 0; + if (!hsfw->imem) + return -ENOMEM; + else + return 0; }
int