linux-stable.git/drivers/gpu/drm/meson, branch v6.0.3 Linux kernel stable tree drm/meson: remove drm bridges at aggregate driver unbind time 2022-10-21T10:39:16+00:00 Adrián Larumbe adrian.larumbe@collabora.com 2022-09-20T22:28:42+00:00 fc1fd114dde3d2623ac37676df3d74ffeedb0da8 [ Upstream commit 09847723c12fc2753749cec3939a02ee92dac468 ] drm bridges added by meson_encoder_hdmi_init and meson_encoder_cvbs_init were not manually removed at module unload time, which caused dangling references to freed memory to remain linked in the global bridge_list. When loading the driver modules back in, the same functions would again call drm_bridge_add, and when traversing the global bridge_list, would end up peeking into freed memory. Once again KASAN revealed the problem: [ +0.000095] ============================================================= [ +0.000008] BUG: KASAN: use-after-free in __list_add_valid+0x9c/0x120 [ +0.000018] Read of size 8 at addr ffff00003da291f0 by task modprobe/2483 [ +0.000018] CPU: 3 PID: 2483 Comm: modprobe Tainted: G C O 5.19.0-rc6-lrmbkasan+ #1 [ +0.000011] Hardware name: Hardkernel ODROID-N2Plus (DT) [ +0.000008] Call trace: [ +0.000006] dump_backtrace+0x1ec/0x280 [ +0.000012] show_stack+0x24/0x80 [ +0.000008] dump_stack_lvl+0x98/0xd4 [ +0.000011] print_address_description.constprop.0+0x80/0x520 [ +0.000011] print_report+0x128/0x260 [ +0.000008] kasan_report+0xb8/0xfc [ +0.000008] __asan_report_load8_noabort+0x3c/0x50 [ +0.000009] __list_add_valid+0x9c/0x120 [ +0.000009] drm_bridge_add+0x6c/0x104 [drm] [ +0.000165] dw_hdmi_probe+0x1900/0x2360 [dw_hdmi] [ +0.000022] meson_dw_hdmi_bind+0x520/0x814 [meson_dw_hdmi] [ +0.000014] component_bind+0x174/0x520 [ +0.000012] component_bind_all+0x1a8/0x38c [ +0.000010] meson_drv_bind_master+0x5e8/0xb74 [meson_drm] [ +0.000032] meson_drv_bind+0x20/0x2c [meson_drm] [ +0.000027] try_to_bring_up_aggregate_device+0x19c/0x390 [ +0.000010] component_master_add_with_match+0x1c8/0x284 [ +0.000009] meson_drv_probe+0x274/0x280 [meson_drm] [ +0.000026] platform_probe+0xd0/0x220 [ +0.000009] really_probe+0x3ac/0xa80 [ +0.000009] __driver_probe_device+0x1f8/0x400 [ +0.000009] driver_probe_device+0x68/0x1b0 [ +0.000009] __driver_attach+0x20c/0x480 [ +0.000008] bus_for_each_dev+0x114/0x1b0 [ +0.000009] driver_attach+0x48/0x64 [ +0.000008] bus_add_driver+0x390/0x564 [ +0.000009] driver_register+0x1a8/0x3e4 [ +0.000009] __platform_driver_register+0x6c/0x94 [ +0.000008] meson_drm_platform_driver_init+0x3c/0x1000 [meson_drm] [ +0.000027] do_one_initcall+0xc4/0x2b0 [ +0.000011] do_init_module+0x154/0x570 [ +0.000011] load_module+0x1a78/0x1ea4 [ +0.000008] __do_sys_init_module+0x184/0x1cc [ +0.000009] __arm64_sys_init_module+0x78/0xb0 [ +0.000009] invoke_syscall+0x74/0x260 [ +0.000009] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000012] el0t_64_sync_handler+0x11c/0x150 [ +0.000008] el0t_64_sync+0x18c/0x190 [ +0.000016] Allocated by task 879: [ +0.000008] kasan_save_stack+0x2c/0x5c [ +0.000011] __kasan_kmalloc+0x90/0xd0 [ +0.000007] __kmalloc+0x278/0x4a0 [ +0.000011] mpi_resize+0x13c/0x1d0 [ +0.000011] mpi_powm+0xd24/0x1570 [ +0.000009] rsa_enc+0x1a4/0x30c [ +0.000009] pkcs1pad_verify+0x3f0/0x580 [ +0.000009] public_key_verify_signature+0x7a8/0xba4 [ +0.000010] public_key_verify_signature_2+0x40/0x60 [ +0.000008] verify_signature+0xb4/0x114 [ +0.000008] pkcs7_validate_trust_one.constprop.0+0x3b8/0x574 [ +0.000009] pkcs7_validate_trust+0xb8/0x15c [ +0.000008] verify_pkcs7_message_sig+0xec/0x1b0 [ +0.000012] verify_pkcs7_signature+0x78/0xac [ +0.000007] mod_verify_sig+0x110/0x190 [ +0.000009] module_sig_check+0x114/0x1e0 [ +0.000009] load_module+0xa0/0x1ea4 [ +0.000008] __do_sys_init_module+0x184/0x1cc [ +0.000008] __arm64_sys_init_module+0x78/0xb0 [ +0.000008] invoke_syscall+0x74/0x260 [ +0.000009] el0_svc_common.constprop.0+0x1a8/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000009] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64_sync+0x18c/0x190 [ +0.000013] Freed by task 2422: [ +0.000008] kasan_save_stack+0x2c/0x5c [ +0.000009] kasan_set_track+0x2c/0x40 [ +0.000007] kasan_set_free_info+0x28/0x50 [ +0.000009] ____kasan_slab_free+0x128/0x1d4 [ +0.000008] __kasan_slab_free+0x18/0x24 [ +0.000007] slab_free_freelist_hook+0x108/0x230 [ +0.000010] kfree+0x110/0x35c [ +0.000008] release_nodes+0xf0/0x16c [ +0.000009] devres_release_group+0x180/0x270 [ +0.000008] take_down_aggregate_device+0xcc/0x160 [ +0.000010] component_del+0x18c/0x360 [ +0.000009] meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi] [ +0.000013] platform_remove+0x64/0xb0 [ +0.000008] device_remove+0xb8/0x154 [ +0.000009] device_release_driver_internal+0x398/0x5b0 [ +0.000009] driver_detach+0xac/0x1b0 [ +0.000009] bus_remove_driver+0x158/0x29c [ +0.000008] driver_unregister+0x70/0xb0 [ +0.000009] platform_driver_unregister+0x20/0x2c [ +0.000007] meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi] [ +0.000012] __do_sys_delete_module+0x288/0x400 [ +0.000009] __arm64_sys_delete_module+0x5c/0x80 [ +0.000009] invoke_syscall+0x74/0x260 [ +0.000008] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000008] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64_sync+0x18c/0x190 [ +0.000013] The buggy address belongs to the object at ffff00003da29000 which belongs to the cache kmalloc-1k of size 1024 [ +0.000008] The buggy address is located 496 bytes inside of 1024-byte region [ffff00003da29000, ffff00003da29400) [ +0.000015] The buggy address belongs to the physical page: [ +0.000009] page:fffffc0000f68a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3da28 [ +0.000012] head:fffffc0000f68a00 order:3 compound_mapcount:0 compound_pincount:0 [ +0.000009] flags: 0xffff00000010200(slab|head|node=0|zone=0|lastcpupid=0xffff) [ +0.000019] raw: 0ffff00000010200 fffffc0000eb5c08 fffffc0000d96608 ffff000000002a80 [ +0.000008] raw: 0000000000000000 00000000000a000a 00000001ffffffff 0000000000000000 [ +0.000008] page dumped because: kasan: bad access detected [ +0.000011] Memory state around the buggy address: [ +0.000009] ffff00003da29080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ffff00003da29100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] >ffff00003da29180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ^ [ +0.000008] ffff00003da29200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000006] ffff00003da29280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ================================================================== Fix by keeping track of which encoders were initialised in the meson_drm structure and manually removing their bridges at aggregate driver's unbind time. Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220920222842.1053234-1-adrian.larumbe@collabora.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 09847723c12fc2753749cec3939a02ee92dac468 ]

drm bridges added by meson_encoder_hdmi_init and meson_encoder_cvbs_init
were not manually removed at module unload time, which caused dangling
references to freed memory to remain linked in the global bridge_list.

When loading the driver modules back in, the same functions would again
call drm_bridge_add, and when traversing the global bridge_list, would
end up peeking into freed memory.

Once again KASAN revealed the problem:

[  +0.000095] =============================================================
[  +0.000008] BUG: KASAN: use-after-free in __list_add_valid+0x9c/0x120
[  +0.000018] Read of size 8 at addr ffff00003da291f0 by task modprobe/2483

[  +0.000018] CPU: 3 PID: 2483 Comm: modprobe Tainted: G         C O      5.19.0-rc6-lrmbkasan+ #1
[  +0.000011] Hardware name: Hardkernel ODROID-N2Plus (DT)
[  +0.000008] Call trace:
[  +0.000006]  dump_backtrace+0x1ec/0x280
[  +0.000012]  show_stack+0x24/0x80
[  +0.000008]  dump_stack_lvl+0x98/0xd4
[  +0.000011]  print_address_description.constprop.0+0x80/0x520
[  +0.000011]  print_report+0x128/0x260
[  +0.000008]  kasan_report+0xb8/0xfc
[  +0.000008]  __asan_report_load8_noabort+0x3c/0x50
[  +0.000009]  __list_add_valid+0x9c/0x120
[  +0.000009]  drm_bridge_add+0x6c/0x104 [drm]
[  +0.000165]  dw_hdmi_probe+0x1900/0x2360 [dw_hdmi]
[  +0.000022]  meson_dw_hdmi_bind+0x520/0x814 [meson_dw_hdmi]
[  +0.000014]  component_bind+0x174/0x520
[  +0.000012]  component_bind_all+0x1a8/0x38c
[  +0.000010]  meson_drv_bind_master+0x5e8/0xb74 [meson_drm]
[  +0.000032]  meson_drv_bind+0x20/0x2c [meson_drm]
[  +0.000027]  try_to_bring_up_aggregate_device+0x19c/0x390
[  +0.000010]  component_master_add_with_match+0x1c8/0x284
[  +0.000009]  meson_drv_probe+0x274/0x280 [meson_drm]
[  +0.000026]  platform_probe+0xd0/0x220
[  +0.000009]  really_probe+0x3ac/0xa80
[  +0.000009]  __driver_probe_device+0x1f8/0x400
[  +0.000009]  driver_probe_device+0x68/0x1b0
[  +0.000009]  __driver_attach+0x20c/0x480
[  +0.000008]  bus_for_each_dev+0x114/0x1b0
[  +0.000009]  driver_attach+0x48/0x64
[  +0.000008]  bus_add_driver+0x390/0x564
[  +0.000009]  driver_register+0x1a8/0x3e4
[  +0.000009]  __platform_driver_register+0x6c/0x94
[  +0.000008]  meson_drm_platform_driver_init+0x3c/0x1000 [meson_drm]
[  +0.000027]  do_one_initcall+0xc4/0x2b0
[  +0.000011]  do_init_module+0x154/0x570
[  +0.000011]  load_module+0x1a78/0x1ea4
[  +0.000008]  __do_sys_init_module+0x184/0x1cc
[  +0.000009]  __arm64_sys_init_module+0x78/0xb0
[  +0.000009]  invoke_syscall+0x74/0x260
[  +0.000009]  el0_svc_common.constprop.0+0xcc/0x260
[  +0.000008]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000012]  el0t_64_sync_handler+0x11c/0x150
[  +0.000008]  el0t_64_sync+0x18c/0x190

[  +0.000016] Allocated by task 879:
[  +0.000008]  kasan_save_stack+0x2c/0x5c
[  +0.000011]  __kasan_kmalloc+0x90/0xd0
[  +0.000007]  __kmalloc+0x278/0x4a0
[  +0.000011]  mpi_resize+0x13c/0x1d0
[  +0.000011]  mpi_powm+0xd24/0x1570
[  +0.000009]  rsa_enc+0x1a4/0x30c
[  +0.000009]  pkcs1pad_verify+0x3f0/0x580
[  +0.000009]  public_key_verify_signature+0x7a8/0xba4
[  +0.000010]  public_key_verify_signature_2+0x40/0x60
[  +0.000008]  verify_signature+0xb4/0x114
[  +0.000008]  pkcs7_validate_trust_one.constprop.0+0x3b8/0x574
[  +0.000009]  pkcs7_validate_trust+0xb8/0x15c
[  +0.000008]  verify_pkcs7_message_sig+0xec/0x1b0
[  +0.000012]  verify_pkcs7_signature+0x78/0xac
[  +0.000007]  mod_verify_sig+0x110/0x190
[  +0.000009]  module_sig_check+0x114/0x1e0
[  +0.000009]  load_module+0xa0/0x1ea4
[  +0.000008]  __do_sys_init_module+0x184/0x1cc
[  +0.000008]  __arm64_sys_init_module+0x78/0xb0
[  +0.000008]  invoke_syscall+0x74/0x260
[  +0.000009]  el0_svc_common.constprop.0+0x1a8/0x260
[  +0.000008]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000009]  el0t_64_sync_handler+0x11c/0x150
[  +0.000009]  el0t_64_sync+0x18c/0x190

[  +0.000013] Freed by task 2422:
[  +0.000008]  kasan_save_stack+0x2c/0x5c
[  +0.000009]  kasan_set_track+0x2c/0x40
[  +0.000007]  kasan_set_free_info+0x28/0x50
[  +0.000009]  ____kasan_slab_free+0x128/0x1d4
[  +0.000008]  __kasan_slab_free+0x18/0x24
[  +0.000007]  slab_free_freelist_hook+0x108/0x230
[  +0.000010]  kfree+0x110/0x35c
[  +0.000008]  release_nodes+0xf0/0x16c
[  +0.000009]  devres_release_group+0x180/0x270
[  +0.000008]  take_down_aggregate_device+0xcc/0x160
[  +0.000010]  component_del+0x18c/0x360
[  +0.000009]  meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi]
[  +0.000013]  platform_remove+0x64/0xb0
[  +0.000008]  device_remove+0xb8/0x154
[  +0.000009]  device_release_driver_internal+0x398/0x5b0
[  +0.000009]  driver_detach+0xac/0x1b0
[  +0.000009]  bus_remove_driver+0x158/0x29c
[  +0.000008]  driver_unregister+0x70/0xb0
[  +0.000009]  platform_driver_unregister+0x20/0x2c
[  +0.000007]  meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi]
[  +0.000012]  __do_sys_delete_module+0x288/0x400
[  +0.000009]  __arm64_sys_delete_module+0x5c/0x80
[  +0.000009]  invoke_syscall+0x74/0x260
[  +0.000008]  el0_svc_common.constprop.0+0xcc/0x260
[  +0.000008]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000008]  el0t_64_sync_handler+0x11c/0x150
[  +0.000009]  el0t_64_sync+0x18c/0x190

[  +0.000013] The buggy address belongs to the object at ffff00003da29000
               which belongs to the cache kmalloc-1k of size 1024
[  +0.000008] The buggy address is located 496 bytes inside of
               1024-byte region [ffff00003da29000, ffff00003da29400)

[  +0.000015] The buggy address belongs to the physical page:
[  +0.000009] page:fffffc0000f68a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3da28
[  +0.000012] head:fffffc0000f68a00 order:3 compound_mapcount:0 compound_pincount:0
[  +0.000009] flags: 0xffff00000010200(slab|head|node=0|zone=0|lastcpupid=0xffff)
[  +0.000019] raw: 0ffff00000010200 fffffc0000eb5c08 fffffc0000d96608 ffff000000002a80
[  +0.000008] raw: 0000000000000000 00000000000a000a 00000001ffffffff 0000000000000000
[  +0.000008] page dumped because: kasan: bad access detected

[  +0.000011] Memory state around the buggy address:
[  +0.000009]  ffff00003da29080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007]  ffff00003da29100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007] >ffff00003da29180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007]                                                              ^
[  +0.000008]  ffff00003da29200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000006]  ffff00003da29280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007] ==================================================================

Fix by keeping track of which encoders were initialised in the meson_drm
structure and manually removing their bridges at aggregate driver's unbind
time.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220920222842.1053234-1-adrian.larumbe@collabora.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/meson: explicitly remove aggregate driver at module unload time 2022-10-21T10:39:16+00:00 Adrián Larumbe adrian.larumbe@collabora.com 2022-09-19T01:09:39+00:00 6ef20de2fe0ee1decedbfabb17782897ca27bfe5 [ Upstream commit 8616f2a0589a80e08434212324250eb22f6a66ce ] Because component_master_del wasn't being called when unloading the meson_drm module, the aggregate device would linger forever in the global aggregate_devices list. That means when unloading and reloading the meson_dw_hdmi module, component_add would call into try_to_bring_up_aggregate_device and find the unbound meson_drm aggregate device. This would in turn dereference some of the aggregate_device's struct entries which point to memory automatically freed by the devres API when unbinding the aggregate device from meson_drv_unbind, and trigger an use-after-free bug: [ +0.000014] ============================================================= [ +0.000007] BUG: KASAN: use-after-free in find_components+0x468/0x500 [ +0.000017] Read of size 8 at addr ffff000006731688 by task modprobe/2536 [ +0.000018] CPU: 4 PID: 2536 Comm: modprobe Tainted: G C O 5.19.0-rc6-lrmbkasan+ #1 [ +0.000010] Hardware name: Hardkernel ODROID-N2Plus (DT) [ +0.000008] Call trace: [ +0.000005] dump_backtrace+0x1ec/0x280 [ +0.000011] show_stack+0x24/0x80 [ +0.000007] dump_stack_lvl+0x98/0xd4 [ +0.000010] print_address_description.constprop.0+0x80/0x520 [ +0.000011] print_report+0x128/0x260 [ +0.000007] kasan_report+0xb8/0xfc [ +0.000007] __asan_report_load8_noabort+0x3c/0x50 [ +0.000009] find_components+0x468/0x500 [ +0.000008] try_to_bring_up_aggregate_device+0x64/0x390 [ +0.000009] __component_add+0x1dc/0x49c [ +0.000009] component_add+0x20/0x30 [ +0.000008] meson_dw_hdmi_probe+0x28/0x34 [meson_dw_hdmi] [ +0.000013] platform_probe+0xd0/0x220 [ +0.000008] really_probe+0x3ac/0xa80 [ +0.000008] __driver_probe_device+0x1f8/0x400 [ +0.000008] driver_probe_device+0x68/0x1b0 [ +0.000008] __driver_attach+0x20c/0x480 [ +0.000009] bus_for_each_dev+0x114/0x1b0 [ +0.000007] driver_attach+0x48/0x64 [ +0.000009] bus_add_driver+0x390/0x564 [ +0.000007] driver_register+0x1a8/0x3e4 [ +0.000009] __platform_driver_register+0x6c/0x94 [ +0.000007] meson_dw_hdmi_platform_driver_init+0x30/0x1000 [meson_dw_hdmi] [ +0.000014] do_one_initcall+0xc4/0x2b0 [ +0.000008] do_init_module+0x154/0x570 [ +0.000010] load_module+0x1a78/0x1ea4 [ +0.000008] __do_sys_init_module+0x184/0x1cc [ +0.000008] __arm64_sys_init_module+0x78/0xb0 [ +0.000008] invoke_syscall+0x74/0x260 [ +0.000008] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000009] do_el0_svc+0x50/0x70 [ +0.000008] el0_svc+0x68/0x1a0 [ +0.000009] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64_sync+0x18c/0x190 [ +0.000014] Allocated by task 902: [ +0.000007] kasan_save_stack+0x2c/0x5c [ +0.000009] __kasan_kmalloc+0x90/0xd0 [ +0.000007] __kmalloc_node+0x240/0x580 [ +0.000010] memcg_alloc_slab_cgroups+0xa4/0x1ac [ +0.000010] memcg_slab_post_alloc_hook+0xbc/0x4c0 [ +0.000008] kmem_cache_alloc_node+0x1d0/0x490 [ +0.000009] __alloc_skb+0x1d4/0x310 [ +0.000010] alloc_skb_with_frags+0x8c/0x620 [ +0.000008] sock_alloc_send_pskb+0x5ac/0x6d0 [ +0.000010] unix_dgram_sendmsg+0x2e0/0x12f0 [ +0.000010] sock_sendmsg+0xcc/0x110 [ +0.000007] sock_write_iter+0x1d0/0x304 [ +0.000008] new_sync_write+0x364/0x460 [ +0.000007] vfs_write+0x420/0x5ac [ +0.000008] ksys_write+0x19c/0x1f0 [ +0.000008] __arm64_sys_write+0x78/0xb0 [ +0.000007] invoke_syscall+0x74/0x260 [ +0.000008] el0_svc_common.constprop.0+0x1a8/0x260 [ +0.000009] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000008] el0t_64_sync_handler+0x11c/0x150 [ +0.000008] el0t_64_sync+0x18c/0x190 [ +0.000013] Freed by task 2509: [ +0.000008] kasan_save_stack+0x2c/0x5c [ +0.000007] kasan_set_track+0x2c/0x40 [ +0.000008] kasan_set_free_info+0x28/0x50 [ +0.000008] ____kasan_slab_free+0x128/0x1d4 [ +0.000008] __kasan_slab_free+0x18/0x24 [ +0.000007] slab_free_freelist_hook+0x108/0x230 [ +0.000010] kfree+0x110/0x35c [ +0.000008] release_nodes+0xf0/0x16c [ +0.000008] devres_release_all+0xfc/0x180 [ +0.000008] device_unbind_cleanup+0x24/0x164 [ +0.000008] device_release_driver_internal+0x3e8/0x5b0 [ +0.000010] driver_detach+0xac/0x1b0 [ +0.000008] bus_remove_driver+0x158/0x29c [ +0.000008] driver_unregister+0x70/0xb0 [ +0.000009] platform_driver_unregister+0x20/0x2c [ +0.000007] 0xffff800003722d98 [ +0.000012] __do_sys_delete_module+0x288/0x400 [ +0.000009] __arm64_sys_delete_module+0x5c/0x80 [ +0.000008] invoke_syscall+0x74/0x260 [ +0.000008] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000008] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64_sync+0x18c/0x190 [ +0.000013] Last potentially related work creation: [ +0.000007] kasan_save_stack+0x2c/0x5c [ +0.000007] __kasan_record_aux_stack+0xb8/0xf0 [ +0.000009] kasan_record_aux_stack_noalloc+0x14/0x20 [ +0.000008] insert_work+0x54/0x290 [ +0.000009] __queue_work+0x48c/0xd24 [ +0.000008] queue_work_on+0x90/0x11c [ +0.000008] call_usermodehelper_exec+0x188/0x404 [ +0.000010] kobject_uevent_env+0x5a8/0x794 [ +0.000010] kobject_uevent+0x14/0x20 [ +0.000008] driver_register+0x230/0x3e4 [ +0.000009] __platform_driver_register+0x6c/0x94 [ +0.000007] gxbb_driver_init+0x28/0x34 [ +0.000010] do_one_initcall+0xc4/0x2b0 [ +0.000008] do_initcalls+0x20c/0x24c [ +0.000010] kernel_init_freeable+0x22c/0x278 [ +0.000009] kernel_init+0x3c/0x170 [ +0.000008] ret_from_fork+0x10/0x20 [ +0.000013] The buggy address belongs to the object at ffff000006731600 which belongs to the cache kmalloc-256 of size 256 [ +0.000009] The buggy address is located 136 bytes inside of 256-byte region [ffff000006731600, ffff000006731700) [ +0.000015] The buggy address belongs to the physical page: [ +0.000008] page:fffffc000019cc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff000006730a00 pfn:0x6730 [ +0.000011] head:fffffc000019cc00 order:2 compound_mapcount:0 compound_pincount:0 [ +0.000008] flags: 0xffff00000010200(slab|head|node=0|zone=0|lastcpupid=0xffff) [ +0.000016] raw: 0ffff00000010200 fffffc00000c3d08 fffffc0000ef2b08 ffff000000002680 [ +0.000009] raw: ffff000006730a00 0000000000150014 00000001ffffffff 0000000000000000 [ +0.000006] page dumped because: kasan: bad access detected [ +0.000011] Memory state around the buggy address: [ +0.000007] ffff000006731580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ +0.000007] ffff000006731600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] >ffff000006731680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ^ [ +0.000006] ffff000006731700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ +0.000007] ffff000006731780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ +0.000006] ================================================================== Fix by adding 'remove' driver callback for meson-drm, and explicitly deleting the aggregate device. Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220919010940.419893-3-adrian.larumbe@collabora.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 8616f2a0589a80e08434212324250eb22f6a66ce ]

Because component_master_del wasn't being called when unloading the
meson_drm module, the aggregate device would linger forever in the global
aggregate_devices list. That means when unloading and reloading the
meson_dw_hdmi module, component_add would call into
try_to_bring_up_aggregate_device and find the unbound meson_drm aggregate
device.

This would in turn dereference some of the aggregate_device's struct
entries which point to memory automatically freed by the devres API when
unbinding the aggregate device from meson_drv_unbind, and trigger an
use-after-free bug:

[  +0.000014] =============================================================
[  +0.000007] BUG: KASAN: use-after-free in find_components+0x468/0x500
[  +0.000017] Read of size 8 at addr ffff000006731688 by task modprobe/2536
[  +0.000018] CPU: 4 PID: 2536 Comm: modprobe Tainted: G         C O      5.19.0-rc6-lrmbkasan+ #1
[  +0.000010] Hardware name: Hardkernel ODROID-N2Plus (DT)
[  +0.000008] Call trace:
[  +0.000005]  dump_backtrace+0x1ec/0x280
[  +0.000011]  show_stack+0x24/0x80
[  +0.000007]  dump_stack_lvl+0x98/0xd4
[  +0.000010]  print_address_description.constprop.0+0x80/0x520
[  +0.000011]  print_report+0x128/0x260
[  +0.000007]  kasan_report+0xb8/0xfc
[  +0.000007]  __asan_report_load8_noabort+0x3c/0x50
[  +0.000009]  find_components+0x468/0x500
[  +0.000008]  try_to_bring_up_aggregate_device+0x64/0x390
[  +0.000009]  __component_add+0x1dc/0x49c
[  +0.000009]  component_add+0x20/0x30
[  +0.000008]  meson_dw_hdmi_probe+0x28/0x34 [meson_dw_hdmi]
[  +0.000013]  platform_probe+0xd0/0x220
[  +0.000008]  really_probe+0x3ac/0xa80
[  +0.000008]  __driver_probe_device+0x1f8/0x400
[  +0.000008]  driver_probe_device+0x68/0x1b0
[  +0.000008]  __driver_attach+0x20c/0x480
[  +0.000009]  bus_for_each_dev+0x114/0x1b0
[  +0.000007]  driver_attach+0x48/0x64
[  +0.000009]  bus_add_driver+0x390/0x564
[  +0.000007]  driver_register+0x1a8/0x3e4
[  +0.000009]  __platform_driver_register+0x6c/0x94
[  +0.000007]  meson_dw_hdmi_platform_driver_init+0x30/0x1000 [meson_dw_hdmi]
[  +0.000014]  do_one_initcall+0xc4/0x2b0
[  +0.000008]  do_init_module+0x154/0x570
[  +0.000010]  load_module+0x1a78/0x1ea4
[  +0.000008]  __do_sys_init_module+0x184/0x1cc
[  +0.000008]  __arm64_sys_init_module+0x78/0xb0
[  +0.000008]  invoke_syscall+0x74/0x260
[  +0.000008]  el0_svc_common.constprop.0+0xcc/0x260
[  +0.000009]  do_el0_svc+0x50/0x70
[  +0.000008]  el0_svc+0x68/0x1a0
[  +0.000009]  el0t_64_sync_handler+0x11c/0x150
[  +0.000009]  el0t_64_sync+0x18c/0x190

[  +0.000014] Allocated by task 902:
[  +0.000007]  kasan_save_stack+0x2c/0x5c
[  +0.000009]  __kasan_kmalloc+0x90/0xd0
[  +0.000007]  __kmalloc_node+0x240/0x580
[  +0.000010]  memcg_alloc_slab_cgroups+0xa4/0x1ac
[  +0.000010]  memcg_slab_post_alloc_hook+0xbc/0x4c0
[  +0.000008]  kmem_cache_alloc_node+0x1d0/0x490
[  +0.000009]  __alloc_skb+0x1d4/0x310
[  +0.000010]  alloc_skb_with_frags+0x8c/0x620
[  +0.000008]  sock_alloc_send_pskb+0x5ac/0x6d0
[  +0.000010]  unix_dgram_sendmsg+0x2e0/0x12f0
[  +0.000010]  sock_sendmsg+0xcc/0x110
[  +0.000007]  sock_write_iter+0x1d0/0x304
[  +0.000008]  new_sync_write+0x364/0x460
[  +0.000007]  vfs_write+0x420/0x5ac
[  +0.000008]  ksys_write+0x19c/0x1f0
[  +0.000008]  __arm64_sys_write+0x78/0xb0
[  +0.000007]  invoke_syscall+0x74/0x260
[  +0.000008]  el0_svc_common.constprop.0+0x1a8/0x260
[  +0.000009]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000008]  el0t_64_sync_handler+0x11c/0x150
[  +0.000008]  el0t_64_sync+0x18c/0x190

[  +0.000013] Freed by task 2509:
[  +0.000008]  kasan_save_stack+0x2c/0x5c
[  +0.000007]  kasan_set_track+0x2c/0x40
[  +0.000008]  kasan_set_free_info+0x28/0x50
[  +0.000008]  ____kasan_slab_free+0x128/0x1d4
[  +0.000008]  __kasan_slab_free+0x18/0x24
[  +0.000007]  slab_free_freelist_hook+0x108/0x230
[  +0.000010]  kfree+0x110/0x35c
[  +0.000008]  release_nodes+0xf0/0x16c
[  +0.000008]  devres_release_all+0xfc/0x180
[  +0.000008]  device_unbind_cleanup+0x24/0x164
[  +0.000008]  device_release_driver_internal+0x3e8/0x5b0
[  +0.000010]  driver_detach+0xac/0x1b0
[  +0.000008]  bus_remove_driver+0x158/0x29c
[  +0.000008]  driver_unregister+0x70/0xb0
[  +0.000009]  platform_driver_unregister+0x20/0x2c
[  +0.000007]  0xffff800003722d98
[  +0.000012]  __do_sys_delete_module+0x288/0x400
[  +0.000009]  __arm64_sys_delete_module+0x5c/0x80
[  +0.000008]  invoke_syscall+0x74/0x260
[  +0.000008]  el0_svc_common.constprop.0+0xcc/0x260
[  +0.000008]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000008]  el0t_64_sync_handler+0x11c/0x150
[  +0.000009]  el0t_64_sync+0x18c/0x190

[  +0.000013] Last potentially related work creation:
[  +0.000007]  kasan_save_stack+0x2c/0x5c
[  +0.000007]  __kasan_record_aux_stack+0xb8/0xf0
[  +0.000009]  kasan_record_aux_stack_noalloc+0x14/0x20
[  +0.000008]  insert_work+0x54/0x290
[  +0.000009]  __queue_work+0x48c/0xd24
[  +0.000008]  queue_work_on+0x90/0x11c
[  +0.000008]  call_usermodehelper_exec+0x188/0x404
[  +0.000010]  kobject_uevent_env+0x5a8/0x794
[  +0.000010]  kobject_uevent+0x14/0x20
[  +0.000008]  driver_register+0x230/0x3e4
[  +0.000009]  __platform_driver_register+0x6c/0x94
[  +0.000007]  gxbb_driver_init+0x28/0x34
[  +0.000010]  do_one_initcall+0xc4/0x2b0
[  +0.000008]  do_initcalls+0x20c/0x24c
[  +0.000010]  kernel_init_freeable+0x22c/0x278
[  +0.000009]  kernel_init+0x3c/0x170
[  +0.000008]  ret_from_fork+0x10/0x20

[  +0.000013] The buggy address belongs to the object at ffff000006731600
               which belongs to the cache kmalloc-256 of size 256
[  +0.000009] The buggy address is located 136 bytes inside of
               256-byte region [ffff000006731600, ffff000006731700)

[  +0.000015] The buggy address belongs to the physical page:
[  +0.000008] page:fffffc000019cc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff000006730a00 pfn:0x6730
[  +0.000011] head:fffffc000019cc00 order:2 compound_mapcount:0 compound_pincount:0
[  +0.000008] flags: 0xffff00000010200(slab|head|node=0|zone=0|lastcpupid=0xffff)
[  +0.000016] raw: 0ffff00000010200 fffffc00000c3d08 fffffc0000ef2b08 ffff000000002680
[  +0.000009] raw: ffff000006730a00 0000000000150014 00000001ffffffff 0000000000000000
[  +0.000006] page dumped because: kasan: bad access detected

[  +0.000011] Memory state around the buggy address:
[  +0.000007]  ffff000006731580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  +0.000007]  ffff000006731600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007] >ffff000006731680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007]                       ^
[  +0.000006]  ffff000006731700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  +0.000007]  ffff000006731780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  +0.000006] ==================================================================

Fix by adding 'remove' driver callback for meson-drm, and explicitly deleting the
aggregate device.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220919010940.419893-3-adrian.larumbe@collabora.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/meson: reorder driver deinit sequence to fix use-after-free bug 2022-10-21T10:39:16+00:00 Adrián Larumbe adrian.larumbe@collabora.com 2022-09-19T01:09:38+00:00 9d33348513c36337f91f1991da23f41514d4de39 [ Upstream commit 31c519981eb141c7ec39bfd5be25d35f02edb868 ] Unloading the driver triggers the following KASAN warning: [ +0.006275] ============================================================= [ +0.000029] BUG: KASAN: use-after-free in __list_del_entry_valid+0xe0/0x1a0 [ +0.000026] Read of size 8 at addr ffff000020c395e0 by task rmmod/2695 [ +0.000019] CPU: 5 PID: 2695 Comm: rmmod Tainted: G C O 5.19.0-rc6-lrmbkasan+ #1 [ +0.000013] Hardware name: Hardkernel ODROID-N2Plus (DT) [ +0.000008] Call trace: [ +0.000007] dump_backtrace+0x1ec/0x280 [ +0.000013] show_stack+0x24/0x80 [ +0.000008] dump_stack_lvl+0x98/0xd4 [ +0.000011] print_address_description.constprop.0+0x80/0x520 [ +0.000011] print_report+0x128/0x260 [ +0.000007] kasan_report+0xb8/0xfc [ +0.000008] __asan_report_load8_noabort+0x3c/0x50 [ +0.000010] __list_del_entry_valid+0xe0/0x1a0 [ +0.000009] drm_atomic_private_obj_fini+0x30/0x200 [drm] [ +0.000172] drm_bridge_detach+0x94/0x260 [drm] [ +0.000145] drm_encoder_cleanup+0xa4/0x290 [drm] [ +0.000144] drm_mode_config_cleanup+0x118/0x740 [drm] [ +0.000143] drm_mode_config_init_release+0x1c/0x2c [drm] [ +0.000144] drm_managed_release+0x170/0x414 [drm] [ +0.000142] drm_dev_put.part.0+0xc0/0x124 [drm] [ +0.000143] drm_dev_put+0x20/0x30 [drm] [ +0.000142] meson_drv_unbind+0x1d8/0x2ac [meson_drm] [ +0.000028] take_down_aggregate_device+0xb0/0x160 [ +0.000016] component_del+0x18c/0x360 [ +0.000009] meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi] [ +0.000015] platform_remove+0x64/0xb0 [ +0.000009] device_remove+0xb8/0x154 [ +0.000009] device_release_driver_internal+0x398/0x5b0 [ +0.000009] driver_detach+0xac/0x1b0 [ +0.000009] bus_remove_driver+0x158/0x29c [ +0.000009] driver_unregister+0x70/0xb0 [ +0.000008] platform_driver_unregister+0x20/0x2c [ +0.000008] meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi] [ +0.000012] __do_sys_delete_module+0x288/0x400 [ +0.000011] __arm64_sys_delete_module+0x5c/0x80 [ +0.000009] invoke_syscall+0x74/0x260 [ +0.000009] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000009] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000012] el0t_64_sync_handler+0x11c/0x150 [ +0.000008] el0t_64_sync+0x18c/0x190 [ +0.000018] Allocated by task 0: [ +0.000007] (stack is not available) [ +0.000011] Freed by task 2695: [ +0.000008] kasan_save_stack+0x2c/0x5c [ +0.000011] kasan_set_track+0x2c/0x40 [ +0.000008] kasan_set_free_info+0x28/0x50 [ +0.000009] ____kasan_slab_free+0x128/0x1d4 [ +0.000008] __kasan_slab_free+0x18/0x24 [ +0.000007] slab_free_freelist_hook+0x108/0x230 [ +0.000011] kfree+0x110/0x35c [ +0.000008] release_nodes+0xf0/0x16c [ +0.000009] devres_release_group+0x180/0x270 [ +0.000008] component_unbind+0x128/0x1e0 [ +0.000010] component_unbind_all+0x1b8/0x264 [ +0.000009] meson_drv_unbind+0x1a0/0x2ac [meson_drm] [ +0.000025] take_down_aggregate_device+0xb0/0x160 [ +0.000009] component_del+0x18c/0x360 [ +0.000009] meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi] [ +0.000012] platform_remove+0x64/0xb0 [ +0.000008] device_remove+0xb8/0x154 [ +0.000009] device_release_driver_internal+0x398/0x5b0 [ +0.000009] driver_detach+0xac/0x1b0 [ +0.000009] bus_remove_driver+0x158/0x29c [ +0.000008] driver_unregister+0x70/0xb0 [ +0.000008] platform_driver_unregister+0x20/0x2c [ +0.000008] meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi] [ +0.000011] __do_sys_delete_module+0x288/0x400 [ +0.000010] __arm64_sys_delete_module+0x5c/0x80 [ +0.000008] invoke_syscall+0x74/0x260 [ +0.000008] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000009] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64_sync+0x18c/0x190 [ +0.000014] The buggy address belongs to the object at ffff000020c39000 which belongs to the cache kmalloc-4k of size 4096 [ +0.000008] The buggy address is located 1504 bytes inside of 4096-byte region [ffff000020c39000, ffff000020c3a000) [ +0.000016] The buggy address belongs to the physical page: [ +0.000009] page:fffffc0000830e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20c38 [ +0.000013] head:fffffc0000830e00 order:3 compound_mapcount:0 compound_pincount:0 [ +0.000008] flags: 0xffff00000010200(slab|head|node=0|zone=0|lastcpupid=0xffff) [ +0.000019] raw: 0ffff00000010200 fffffc0000fd4808 fffffc0000126208 ffff000000002e80 [ +0.000009] raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000 [ +0.000008] page dumped because: kasan: bad access detected [ +0.000011] Memory state around the buggy address: [ +0.000008] ffff000020c39480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ffff000020c39500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] >ffff000020c39580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ^ [ +0.000007] ffff000020c39600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ffff000020c39680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000006] ================================================================== The reason this is happening is unloading meson-dw-hdmi will cause the component API to take down the aggregate device, which in turn will cause all devres-managed memory to be freed, including the struct dw_hdmi allocated in dw_hdmi_probe. This struct embeds a struct drm_bridge that is added at the end of the function, and which is later on picked up in meson_encoder_hdmi_init. However, when attaching the bridge to the encoder created in meson_encoder_hdmi_init, it's linked to the encoder's bridge chain, from where it never leaves, even after devres_release_group is called when the driver's components are unbound and the embedding structure freed. Then, when calling drm_dev_put in the aggregate driver's unbind function, drm_bridge_detach is called for every single bridge linked to the encoder, including the one whose memory had already been deallocated. Fix by calling component_unbind_all after drm_dev_put. Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220919010940.419893-2-adrian.larumbe@collabora.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 31c519981eb141c7ec39bfd5be25d35f02edb868 ]

Unloading the driver triggers the following KASAN warning:

[  +0.006275] =============================================================
[  +0.000029] BUG: KASAN: use-after-free in __list_del_entry_valid+0xe0/0x1a0
[  +0.000026] Read of size 8 at addr ffff000020c395e0 by task rmmod/2695

[  +0.000019] CPU: 5 PID: 2695 Comm: rmmod Tainted: G         C O      5.19.0-rc6-lrmbkasan+ #1
[  +0.000013] Hardware name: Hardkernel ODROID-N2Plus (DT)
[  +0.000008] Call trace:
[  +0.000007]  dump_backtrace+0x1ec/0x280
[  +0.000013]  show_stack+0x24/0x80
[  +0.000008]  dump_stack_lvl+0x98/0xd4
[  +0.000011]  print_address_description.constprop.0+0x80/0x520
[  +0.000011]  print_report+0x128/0x260
[  +0.000007]  kasan_report+0xb8/0xfc
[  +0.000008]  __asan_report_load8_noabort+0x3c/0x50
[  +0.000010]  __list_del_entry_valid+0xe0/0x1a0
[  +0.000009]  drm_atomic_private_obj_fini+0x30/0x200 [drm]
[  +0.000172]  drm_bridge_detach+0x94/0x260 [drm]
[  +0.000145]  drm_encoder_cleanup+0xa4/0x290 [drm]
[  +0.000144]  drm_mode_config_cleanup+0x118/0x740 [drm]
[  +0.000143]  drm_mode_config_init_release+0x1c/0x2c [drm]
[  +0.000144]  drm_managed_release+0x170/0x414 [drm]
[  +0.000142]  drm_dev_put.part.0+0xc0/0x124 [drm]
[  +0.000143]  drm_dev_put+0x20/0x30 [drm]
[  +0.000142]  meson_drv_unbind+0x1d8/0x2ac [meson_drm]
[  +0.000028]  take_down_aggregate_device+0xb0/0x160
[  +0.000016]  component_del+0x18c/0x360
[  +0.000009]  meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi]
[  +0.000015]  platform_remove+0x64/0xb0
[  +0.000009]  device_remove+0xb8/0x154
[  +0.000009]  device_release_driver_internal+0x398/0x5b0
[  +0.000009]  driver_detach+0xac/0x1b0
[  +0.000009]  bus_remove_driver+0x158/0x29c
[  +0.000009]  driver_unregister+0x70/0xb0
[  +0.000008]  platform_driver_unregister+0x20/0x2c
[  +0.000008]  meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi]
[  +0.000012]  __do_sys_delete_module+0x288/0x400
[  +0.000011]  __arm64_sys_delete_module+0x5c/0x80
[  +0.000009]  invoke_syscall+0x74/0x260
[  +0.000009]  el0_svc_common.constprop.0+0xcc/0x260
[  +0.000009]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000012]  el0t_64_sync_handler+0x11c/0x150
[  +0.000008]  el0t_64_sync+0x18c/0x190

[  +0.000018] Allocated by task 0:
[  +0.000007] (stack is not available)

[  +0.000011] Freed by task 2695:
[  +0.000008]  kasan_save_stack+0x2c/0x5c
[  +0.000011]  kasan_set_track+0x2c/0x40
[  +0.000008]  kasan_set_free_info+0x28/0x50
[  +0.000009]  ____kasan_slab_free+0x128/0x1d4
[  +0.000008]  __kasan_slab_free+0x18/0x24
[  +0.000007]  slab_free_freelist_hook+0x108/0x230
[  +0.000011]  kfree+0x110/0x35c
[  +0.000008]  release_nodes+0xf0/0x16c
[  +0.000009]  devres_release_group+0x180/0x270
[  +0.000008]  component_unbind+0x128/0x1e0
[  +0.000010]  component_unbind_all+0x1b8/0x264
[  +0.000009]  meson_drv_unbind+0x1a0/0x2ac [meson_drm]
[  +0.000025]  take_down_aggregate_device+0xb0/0x160
[  +0.000009]  component_del+0x18c/0x360
[  +0.000009]  meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi]
[  +0.000012]  platform_remove+0x64/0xb0
[  +0.000008]  device_remove+0xb8/0x154
[  +0.000009]  device_release_driver_internal+0x398/0x5b0
[  +0.000009]  driver_detach+0xac/0x1b0
[  +0.000009]  bus_remove_driver+0x158/0x29c
[  +0.000008]  driver_unregister+0x70/0xb0
[  +0.000008]  platform_driver_unregister+0x20/0x2c
[  +0.000008]  meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi]
[  +0.000011]  __do_sys_delete_module+0x288/0x400
[  +0.000010]  __arm64_sys_delete_module+0x5c/0x80
[  +0.000008]  invoke_syscall+0x74/0x260
[  +0.000008]  el0_svc_common.constprop.0+0xcc/0x260
[  +0.000008]  do_el0_svc+0x50/0x70
[  +0.000007]  el0_svc+0x68/0x1a0
[  +0.000009]  el0t_64_sync_handler+0x11c/0x150
[  +0.000009]  el0t_64_sync+0x18c/0x190

[  +0.000014] The buggy address belongs to the object at ffff000020c39000
               which belongs to the cache kmalloc-4k of size 4096
[  +0.000008] The buggy address is located 1504 bytes inside of
               4096-byte region [ffff000020c39000, ffff000020c3a000)

[  +0.000016] The buggy address belongs to the physical page:
[  +0.000009] page:fffffc0000830e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20c38
[  +0.000013] head:fffffc0000830e00 order:3 compound_mapcount:0 compound_pincount:0
[  +0.000008] flags: 0xffff00000010200(slab|head|node=0|zone=0|lastcpupid=0xffff)
[  +0.000019] raw: 0ffff00000010200 fffffc0000fd4808 fffffc0000126208 ffff000000002e80
[  +0.000009] raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
[  +0.000008] page dumped because: kasan: bad access detected

[  +0.000011] Memory state around the buggy address:
[  +0.000008]  ffff000020c39480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007]  ffff000020c39500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007] >ffff000020c39580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007]                                                        ^
[  +0.000007]  ffff000020c39600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000007]  ffff000020c39680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  +0.000006] ==================================================================

The reason this is happening is unloading meson-dw-hdmi will cause the
component API to take down the aggregate device, which in turn will cause
all devres-managed memory to be freed, including the struct dw_hdmi
allocated in dw_hdmi_probe. This struct embeds a struct drm_bridge that is
added at the end of the function, and which is later on picked up in
meson_encoder_hdmi_init.

However, when attaching the bridge to the encoder created in
meson_encoder_hdmi_init, it's linked to the encoder's bridge chain, from
where it never leaves, even after devres_release_group is called when the
driver's components are unbound and the embedding structure freed.

Then, when calling drm_dev_put in the aggregate driver's unbind function,
drm_bridge_detach is called for every single bridge linked to the encoder,
including the one whose memory had already been deallocated.

Fix by calling component_unbind_all after drm_dev_put.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220919010940.419893-2-adrian.larumbe@collabora.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
drm/meson: Fix OSD1 RGB to YCbCr coefficient 2022-09-09T11:34:06+00:00 Stuart Menefy stuart.menefy@mathembedded.com 2022-09-08T15:52:43+00:00 6463d3930ba5b6addcfc8f80a4543976a2fc7656 VPP_WRAP_OSD1_MATRIX_COEF22.Coeff22 is documented as being bits 0-12, not 16-28. Without this the output tends to have a pink hue, changing it results in better color accuracy. The vendor kernel doesn't use this register. However the code which sets VIU2_OSD1_MATRIX_COEF22 also uses bits 0-12. There is a slightly different style of registers for configuring some of the other matrices, which do use bits 16-28 for this coefficient, but those have names ending in MATRIX_COEF22_30, and this is not one of those. Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com> Fixes: 728883948b0d ("drm/meson: Add G12A Support for VIU setup") Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220908155243.687143-1-stuart.menefy@mathembedded.com 
VPP_WRAP_OSD1_MATRIX_COEF22.Coeff22 is documented as being bits 0-12,
not 16-28.

Without this the output tends to have a pink hue, changing it results
in better color accuracy.

The vendor kernel doesn't use this register. However the code which
sets VIU2_OSD1_MATRIX_COEF22 also uses bits 0-12. There is a slightly
different style of registers for configuring some of the other matrices,
which do use bits 16-28 for this coefficient, but those have names
ending in MATRIX_COEF22_30, and this is not one of those.

Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com>
Fixes: 728883948b0d ("drm/meson: Add G12A Support for VIU setup")
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908155243.687143-1-stuart.menefy@mathembedded.com
drm/meson: Correct OSD1 global alpha value 2022-09-09T11:33:44+00:00 Stuart Menefy stuart.menefy@mathembedded.com 2022-09-08T15:51:03+00:00 6836829c8ea453c9e3e518e61539e35881c8ed5f VIU_OSD1_CTRL_STAT.GLOBAL_ALPHA is a 9 bit field, so the maximum value is 0x100 not 0xff. This matches the vendor kernel. Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com> Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller") Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220908155103.686904-1-stuart.menefy@mathembedded.com 
VIU_OSD1_CTRL_STAT.GLOBAL_ALPHA is a 9 bit field, so the maximum
value is 0x100 not 0xff.

This matches the vendor kernel.

Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com>
Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller")
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908155103.686904-1-stuart.menefy@mathembedded.com
Merge drm/drm-fixes into drm-misc-fixes 2022-08-17T06:40:32+00:00 Thomas Zimmermann tzimmermann@suse.de 2022-08-17T06:40:32+00:00 cf36ae3e5802716617b9e4d902a31048240396b0 Backmerging for v6.0-rc1. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> 
Backmerging for v6.0-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
drm/meson: Fix refcount bugs in meson_vpu_has_available_connectors() 2022-08-08T07:46:22+00:00 Liang He windhl@126.com 2022-07-26T01:07:22+00:00 91b3c8dbe898df158fd2a84675f3a284ff6666f7 In this function, there are two refcount leak bugs: (1) when breaking out of for_each_endpoint_of_node(), we need call the of_node_put() for the 'ep'; (2) we should call of_node_put() for the reference returned by of_graph_get_remote_port() when it is not used anymore. Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller") Signed-off-by: Liang He <windhl@126.com> Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220726010722.1319416-1-windhl@126.com 
In this function, there are two refcount leak bugs:
(1) when breaking out of for_each_endpoint_of_node(), we need call
the of_node_put() for the 'ep';
(2) we should call of_node_put() for the reference returned by
of_graph_get_remote_port() when it is not used anymore.

Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller")
Signed-off-by: Liang He <windhl@126.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220726010722.1319416-1-windhl@126.com
Merge tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic 2022-08-05T17:07:23+00:00 Linus Torvalds torvalds@linux-foundation.org 2022-08-05T17:07:23+00:00 3bd6e5854bf9bb5436d6b533e206561839e3b284 Pull asm-generic updates from Arnd Bergmann: "There are three independent sets of changes: - Sai Prakash Ranjan adds tracing support to the asm-generic version of the MMIO accessors, which is intended to help understand problems with device drivers and has been part of Qualcomm's vendor kernels for many years - A patch from Sebastian Siewior to rework the handling of IRQ stacks in softirqs across architectures, which is needed for enabling PREEMPT_RT - The last patch to remove the CONFIG_VIRT_TO_BUS option and some of the code behind that, after the last users of this old interface made it in through the netdev, scsi, media and staging trees" * tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: uapi: asm-generic: fcntl: Fix typo 'the the' in comment arch/*/: remove CONFIG_VIRT_TO_BUS soc: qcom: geni: Disable MMIO tracing for GENI SE serial: qcom_geni_serial: Disable MMIO tracing for geni serial asm-generic/io: Add logging support for MMIO accessors KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM lib: Add register read/write tracing support drm/meson: Fix overflow implicit truncation warnings irqchip/tegra: Fix overflow implicit truncation warnings coresight: etm4x: Use asm-generic IO memory barriers arm64: io: Use asm-generic high level MMIO accessors arch/*: Disable softirq stacks on PREEMPT_RT. 
Pull asm-generic updates from Arnd Bergmann:
 "There are three independent sets of changes:

   - Sai Prakash Ranjan adds tracing support to the asm-generic version
     of the MMIO accessors, which is intended to help understand
     problems with device drivers and has been part of Qualcomm's vendor
     kernels for many years

   - A patch from Sebastian Siewior to rework the handling of IRQ stacks
     in softirqs across architectures, which is needed for enabling
     PREEMPT_RT

   - The last patch to remove the CONFIG_VIRT_TO_BUS option and some of
     the code behind that, after the last users of this old interface
     made it in through the netdev, scsi, media and staging trees"

* tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  uapi: asm-generic: fcntl: Fix typo 'the the' in comment
  arch/*/: remove CONFIG_VIRT_TO_BUS
  soc: qcom: geni: Disable MMIO tracing for GENI SE
  serial: qcom_geni_serial: Disable MMIO tracing for geni serial
  asm-generic/io: Add logging support for MMIO accessors
  KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM
  lib: Add register read/write tracing support
  drm/meson: Fix overflow implicit truncation warnings
  irqchip/tegra: Fix overflow implicit truncation warnings
  coresight: etm4x: Use asm-generic IO memory barriers
  arm64: io: Use asm-generic high level MMIO accessors
  arch/*: Disable softirq stacks on PREEMPT_RT.
drm: Drop drm_blend.h from drm_crtc.h 2022-06-20T20:53:55+00:00 Ville Syrjälä ville.syrjala@linux.intel.com 2022-06-13T20:03:12+00:00 90bb087f66745ca48f6f5e43df99a1212d89e712 drm_crtc.h has no need for drm_blend.h, so don't include it. Avoids useless rebuilds of the entire universe when touching drm_blend.h. Quite a few placs do currently depend on drm_blend.h without actually including it directly. All of those need to be fixed up. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220613200317.11305-4-ville.syrjala@linux.intel.com Acked-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Jani Nikula <jani.nikula@intel.com> 
drm_crtc.h has no need for drm_blend.h, so don't include it.
Avoids useless rebuilds of the entire universe when
touching drm_blend.h.

Quite a few placs do currently depend on drm_blend.h without
actually including it directly. All of those need to be fixed
up.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220613200317.11305-4-ville.syrjala@linux.intel.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
drm: Drop drm_framebuffer.h from drm_crtc.h 2022-06-20T20:53:55+00:00 Ville Syrjälä ville.syrjala@linux.intel.com 2022-06-14T09:54:49+00:00 720cf96d8fecde29b72e1101f8a567a0ce99594f drm_crtc.h has no need for drm_frambuffer.h, so don't include it. Avoids useless rebuilds of the entire universe when touching drm_framebuffer.h. Quite a few placs do currently depend on drm_framebuffer.h without actually including it directly. All of those need to be fixed up. v2: Fix up msm some more v2: Deal with ingenic and shmobile as well Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220614095449.29311-1-ville.syrjala@linux.intel.com Acked-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Jani Nikula <jani.nikula@intel.com> 
drm_crtc.h has no need for drm_frambuffer.h, so don't include it.
Avoids useless rebuilds of the entire universe when
touching drm_framebuffer.h.

Quite a few placs do currently depend on drm_framebuffer.h without
actually including it directly. All of those need to be fixed
up.

v2: Fix up msm some more
v2: Deal with ingenic and shmobile as well

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220614095449.29311-1-ville.syrjala@linux.intel.com
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>