When Output Resource (dcb->or) value is assigned in
fabricate_dcb_output(), there may be out of bounds access to
dac_users array in case dcb->or is zero because ffs(dcb->or) is
used as index there.
The 'or' argument of fabricate_dcb_output() must be interpreted as a
number of bit to set, not value.
Utilize macros from 'enum nouveau_or' in calls instead of hardcoding.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 2e5702aff395 ("drm/nouveau: fabricate DCB encoder table for iMac G4")
Fixes: 670820c0e6a9 ("drm/nouveau: Workaround incorrect DCB entry on a GeForce3
Ti 200.")
Signed-off-by: Mikhail Kobuk <m.ko...@ispras.ru>
---
Changes in v2:
- Instead of checking ffs(dcb->or), adjust function calls to match
argument semantics
- Link to v1:
https://lore.kernel.org/all/20240331064552.6112-1-m.ko...@ispras.ru/
drivers/gpu/drm/nouveau/nouveau_bios.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_bios.c
b/drivers/gpu/drm/nouveau/nouveau_bios.c
index 479effcf607e..79cfab53f80e 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bios.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bios.c
@@ -23,6 +23,7 @@
*/
#include "nouveau_drv.h"
+#include "nouveau_bios.h"
#include "nouveau_reg.h"
#include "dispnv04/hw.h"
#include "nouveau_encoder.h"
@@ -1677,7 +1678,7 @@ apply_dcb_encoder_quirks(struct drm_device *dev, int idx,
u32 *conn, u32 *conf)
*/
if (nv_match_device(dev, 0x0201, 0x1462, 0x8851)) {
if (*conn == 0xf2005014 && *conf == 0xffffffff) {
- fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS, 1, 1, 1);
+ fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS, 1, 1,
DCB_OUTPUT_B);
return false;
}
}
@@ -1763,26 +1764,26 @@ fabricate_dcb_encoder_table(struct drm_device *dev,
struct nvbios *bios)
#ifdef __powerpc__
/* Apple iMac G4 NV17 */
if (of_machine_is_compatible("PowerMac4,5")) {
- fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS, 0, all_heads, 1);
- fabricate_dcb_output(dcb, DCB_OUTPUT_ANALOG, 1, all_heads, 2);
+ fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS, 0, all_heads,
DCB_OUTPUT_B);
+ fabricate_dcb_output(dcb, DCB_OUTPUT_ANALOG, 1, all_heads,
DCB_OUTPUT_C);
return;
}
#endif
/* Make up some sane defaults */
fabricate_dcb_output(dcb, DCB_OUTPUT_ANALOG,
- bios->legacy.i2c_indices.crt, 1, 1);
+ bios->legacy.i2c_indices.crt, 1, DCB_OUTPUT_B);
if (nv04_tv_identify(dev, bios->legacy.i2c_indices.tv) >= 0)
fabricate_dcb_output(dcb, DCB_OUTPUT_TV,
bios->legacy.i2c_indices.tv,
- all_heads, 0);
+ all_heads, DCB_OUTPUT_A);
else if (bios->tmds.output0_script_ptr ||
bios->tmds.output1_script_ptr)
fabricate_dcb_output(dcb, DCB_OUTPUT_TMDS,
bios->legacy.i2c_indices.panel,
- all_heads, 1);
+ all_heads, DCB_OUTPUT_B);
}
static int
--
2.44.0
