4.19-stable review patch. If anyone has any objections, please let me know.
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From: Mikhail Kobuk m.kobuk@ispras.ru
[ Upstream commit cf92bb778eda7830e79452c6917efa8474a30c1e ]
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.kobuk@ispras.ru Signed-off-by: Danilo Krummrich dakr@redhat.com Link: https://patchwork.freedesktop.org/patch/msgid/20240411110854.16701-1-m.kobuk... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/nouveau/nouveau_bios.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
--- a/drivers/gpu/drm/nouveau/nouveau_bios.c +++ b/drivers/gpu/drm/nouveau/nouveau_bios.c @@ -25,6 +25,7 @@ #include <drm/drmP.h>
#include "nouveau_drv.h" +#include "nouveau_bios.h" #include "nouveau_reg.h" #include "dispnv04/hw.h" #include "nouveau_encoder.h" @@ -1674,7 +1675,7 @@ apply_dcb_encoder_quirks(struct drm_devi */ 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; } } @@ -1760,26 +1761,26 @@ fabricate_dcb_encoder_table(struct drm_d #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