Re: out-of-bounds access in sound/soc/sof/topology.c

Sergey Senozhatsky
2022-04-16T02:22:50Z

Hi,

On (22/04/15 11:00), Pierre-Louis Bossart wrote:
> > Now control data allocations looks as follows
> >
> > scontrol->size = struct_size(scontrol->control_data, chanv,
> > le32_to_cpu(mc->num_channels));
> > scontrol->control_data = kzalloc(scontrol->size, GFP_KERNEL);
> >
> > Which is sizeof(sof_ipc_ctrl_data) + mc->num_channels * sizeof(sof_ipc_ctrl_value_chan)

[..]

>
> I checked the v5.10.111 code and I see the same code, with the max_size being used for sof_control_load_bytes() and no channel-based arithmetic.
>
> Can I ask how you found out about this problem, is this the result of a warning/error reported by a software tool or based on your reviews of the code?

I some KASAN warnings, confirmed. This appears to be when control_data is
allocated as control_data.chanv

scontrol->size = 92 + 1 * sizeof(sof_ipc_ctrl_value_chan)

but being dereferenced as it was control_data.data, so the 8 bytes
"payload" is being used as a 32 bytes "payload".

I'd say the first one is scarier than the second one. This should be
two data->size and one data->data accesses in sof_process_load()

if (ipc_data_size) {
for (i = 0; i < widget->num_kcontrols; i++) {
memcpy(&process->data[offset],
wdata[i].pdata->data,
wdata[i].pdata->size);
offset += wdata[i].pdata->size;
}
}

[ 21.493203] ==================================================================
[ 21.493254] BUG: KASAN: slab-out-of-bounds in sof_widget_ready+0x1710/0x20a8 [snd_sof]
[ 21.493276] Read of size 4 at addr ffff888101d25865 by task udevd/2538

[ 21.493317] CPU: 6 PID: 2538 Comm: udevd Tainted: G U 5.10.111 #20 f82fe8812f39d1966e2c6a66cfdb6cc00489a69b
[ 21.493364] Call Trace:
[ 21.493424] dump_stack+0xb1/0x111
[ 21.493478] print_address_description+0x25/0x4fe
[ 21.493521] ? printk+0x76/0x96
[ 21.493568] kasan_report+0x14f/0x190
[ 21.493639] ? sof_widget_ready+0x1710/0x20a8 [snd_sof 35e04f225667e77b61e030d236a681f127c4c356]
[ 21.493708] ? sof_widget_ready+0x1710/0x20a8 [snd_sof 35e04f225667e77b61e030d236a681f127c4c356]
[ 21.493756] check_memory_region+0x17f/0x183
[ 21.493825] sof_widget_ready+0x1710/0x20a8 [snd_sof 35e04f225667e77b61e030d236a681f127c4c356]
[ 21.493910] ? sof_route_unload+0xb8/0xb8 [snd_sof 35e04f225667e77b61e030d236a681f127c4c356]
[ 21.493959] soc_tplg_dapm_widget_elems_load+0x14c2/0x1758
[ 21.494035] ? soc_tplg_dapm_graph_elems_load+0x320/0x320
[ 21.494079] snd_soc_tplg_component_load+0x309/0x5d7
[ 21.494156] snd_sof_load_topology+0x78/0x115 [snd_sof 35e04f225667e77b61e030d236a681f127c4c356]
[ 21.494228] sof_pcm_probe+0xa4/0xd7 [snd_sof 35e04f225667e77b61e030d236a681f127c4c356]
[ 21.494277] snd_soc_component_probe+0x3b/0x99
[ 21.494321] soc_probe_component+0x2a3/0x4fc
[ 21.494365] snd_soc_bind_card+0x83c/0xfe3
[ 21.494426] devm_snd_soc_register_card+0x48/0x83
[ 21.494474] platform_drv_probe+0x88/0xac
[ 21.494519] really_probe+0x1b2/0x4f1
[ 21.494565] driver_probe_device+0x98/0xd7
[ 21.494609] device_driver_attach+0x71/0x96
[ 21.494651] __driver_attach+0xda/0xe5
[ 21.494691] ? driver_attach+0x2d/0x2d
[ 21.494733] bus_for_each_dev+0xcc/0x102
[ 21.494779] bus_add_driver+0x1cb/0x2e3
[ 21.494827] driver_register+0xd7/0x19c
[ 21.494867] ? 0xffffffffc0c60000
[ 21.494909] do_one_initcall+0x158/0x30c
[ 21.494967] ? intel_bw_atomic_check+0x3ef/0x67b
[ 21.495014] do_init_module+0xe5/0x2dc
[ 21.495060] load_module+0x3d0b/0x411a
[ 21.495129] ? __kasan_slab_free+0x128/0x144
[ 21.495175] __se_sys_finit_module+0x13e/0x166
[ 21.495227] do_syscall_64+0x43/0x55
[ 21.495272] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 21.495314] RIP: 0033:0x7ee05f706899
[ 21.495362] Code: 48 8d 3d 9a bd 0c 00 0f 05 eb ad 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 9f 85 0c 00 f7 d8 64 89 01 48
[ 21.495404] RSP: 002b:00007ffc67d1a128 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 21.495464] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007ee05f706899
[ 21.495500] RDX: 0000000000000004 RSI: 00007ee05f7f8adb RDI: 0000000000000018
[ 21.495537] RBP: 00007ffc67d1a190 R08: 000056d1041460d0 R09: 00007ffc67d1a190
[ 21.495572] R10: 00000000003ebf60 R11: 0000000000000246 R12: 0000000000020000
[ 21.495608] R13: 000056d102cbf6b0 R14: 0000000000000000 R15: 00007ee05f7f8adb

[ 21.495659] Allocated by task 2538:
[ 21.495680] stack_trace_save+0x89/0xb8
[ 21.495698] kasan_save_stack+0x36/0x56
[ 21.495715] __kasan_kmalloc+0xf5/0x10c
[ 21.495734] __kmalloc+0xf4/0x2d2
[ 21.495762] sof_control_load+0x17c/0xaf9 [snd_sof]
[ 21.495782] soc_tplg_dapm_widget_elems_load+0xfa5/0x1758
[ 21.495801] snd_soc_tplg_component_load+0x309/0x5d7
[ 21.495828] snd_sof_load_topology+0x78/0x115 [snd_sof]
[ 21.495854] sof_pcm_probe+0xa4/0xd7 [snd_sof]
[ 21.495873] snd_soc_component_probe+0x3b/0x99
[ 21.495890] soc_probe_component+0x2a3/0x4fc
[ 21.495907] snd_soc_bind_card+0x83c/0xfe3
[ 21.495925] devm_snd_soc_register_card+0x48/0x83
[ 21.495944] platform_drv_probe+0x88/0xac
[ 21.495963] really_probe+0x1b2/0x4f1
[ 21.495981] driver_probe_device+0x98/0xd7
[ 21.495998] device_driver_attach+0x71/0x96
[ 21.496015] __driver_attach+0xda/0xe5
[ 21.496033] bus_for_each_dev+0xcc/0x102
[ 21.496051] bus_add_driver+0x1cb/0x2e3
[ 21.496073] driver_register+0xd7/0x19c
[ 21.496095] do_one_initcall+0x158/0x30c
[ 21.496112] do_init_module+0xe5/0x2dc
[ 21.496129] load_module+0x3d0b/0x411a
[ 21.496146] __se_sys_finit_module+0x13e/0x166
[ 21.496164] do_syscall_64+0x43/0x55
[ 21.496183] entry_SYSCALL_64_after_hwframe+0x44/0xa9

[ 21.496212] The buggy address belongs to the object at ffff888101d25800
which belongs to the cache kmalloc-128 of size 128
[ 21.496232] The buggy address is located 101 bytes inside of
128-byte region [ffff888101d25800, ffff888101d25880)
[ 21.496247] The buggy address belongs to the page:
[ 21.496270] page:000000001cb121a9 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x101d24
[ 21.496287] head:000000001cb121a9 order:1 compound_mapcount:0
[ 21.496305] flags: 0x8000000000010200(slab|head)
[ 21.496329] raw: 8000000000010200 ffffea0004268c80 0000000700000007 ffff888100043680
[ 21.496351] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[ 21.496366] page dumped because: kasan: bad access detected

[ 21.496390] Memory state around the buggy address:
[ 21.496408] ffff888101d25700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 21.496424] ffff888101d25780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 21.496440] >ffff888101d25800: 00 00 00 00 00 00 00 00 00 00 00 00 05 fc fc fc
[ 21.496455] ^
[ 21.496472] ffff888101d25880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 21.496488] ffff888101d25900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 21.496501] ==================================================================

The seconds one is sof_get_control_data()

*size += wdata[i].pdata->size;

[ 20.174619] ==================================================================
[ 20.174672] BUG: KASAN: slab-out-of-bounds in sof_widget_ready+0x1485/0x1f15 [snd_sof]
[ 20.174694] Read of size 4 at addr ffff88813f66aa64 by task udevd/2525

[ 20.174735] CPU: 6 PID: 2525 Comm: udevd Tainted: G U 5.10.111 #15 0affb963ab1ae58c88daed12d4caa605c5149ad7
[ 20.174768] Call Trace:
[ 20.174797] dump_stack+0xb1/0x111
[ 20.174823] print_address_description+0x25/0x4fe
[ 20.174844] ? printk+0x76/0x96
[ 20.174866] kasan_report+0x14f/0x190
[ 20.174898] ? sof_widget_ready+0x1485/0x1f15 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.174929] ? sof_widget_ready+0x12cb/0x1f15 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.174958] ? sof_widget_ready+0x1485/0x1f15 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.174980] check_memory_region+0x17f/0x183
[ 20.175010] sof_widget_ready+0x1485/0x1f15 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.175048] ? sof_route_unload+0xb8/0xb8 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.175072] soc_tplg_dapm_widget_elems_load+0x14c2/0x1758
[ 20.175108] ? soc_tplg_dapm_graph_elems_load+0x320/0x320
[ 20.175128] snd_soc_tplg_component_load+0x309/0x5d7
[ 20.175163] snd_sof_load_topology+0x78/0x115 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.175196] sof_pcm_probe+0xa4/0xd7 [snd_sof ed49f3db2df0d72704365322eabcc747c7cbe78c]
[ 20.175220] snd_soc_component_probe+0x3b/0x99
[ 20.175240] soc_probe_component+0x2a3/0x4fc
[ 20.175261] snd_soc_bind_card+0x83c/0xfe3
[ 20.175288] devm_snd_soc_register_card+0x48/0x83
[ 20.175310] platform_drv_probe+0x88/0xac
[ 20.175331] really_probe+0x1b2/0x4f1
[ 20.175352] driver_probe_device+0x98/0xd7
[ 20.175372] device_driver_attach+0x71/0x96
[ 20.175392] __driver_attach+0xda/0xe5
[ 20.175410] ? driver_attach+0x2d/0x2d
[ 20.175429] bus_for_each_dev+0xcc/0x102
[ 20.175451] bus_add_driver+0x1cb/0x2e3
[ 20.175473] driver_register+0xd7/0x19c
[ 20.175492] ? 0xffffffffc0ec8000
[ 20.175512] do_one_initcall+0x158/0x30c
[ 20.175539] ? intel_bw_atomic_check+0x3ef/0x67b
[ 20.175561] do_init_module+0xe5/0x2dc
[ 20.175582] load_module+0x3d0b/0x411a
[ 20.175615] ? __kasan_slab_free+0x128/0x144
[ 20.175636] __se_sys_finit_module+0x13e/0x166
[ 20.175659] do_syscall_64+0x43/0x55
[ 20.175681] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 20.175699] RIP: 0033:0x78e6c3948899
[ 20.175722] Code: 48 8d 3d 9a bd 0c 00 0f 05 eb ad 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 9f 85 0c 00 f7 d8 64 89 01 48
[ 20.175741] RSP: 002b:00007ffff7b907a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 20.175768] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000078e6c3948899
[ 20.175785] RDX: 0000000000000004 RSI: 000078e6c3a3aadb RDI: 0000000000000017
[ 20.175802] RBP: 00007ffff7b90810 R08: 00005a58cc4cde40 R09: 00007ffff7b90810
[ 20.175818] R10: 00000000003ebf60 R11: 0000000000000246 R12: 0000000000020000
[ 20.175834] R13: 00005a58cb0486b0 R14: 0000000000000000 R15: 000078e6c3a3aadb

[ 20.175865] Allocated by task 2525:
[ 20.175885] stack_trace_save+0x89/0xb8
[ 20.175903] kasan_save_stack+0x36/0x56
[ 20.175920] __kasan_kmalloc+0xf5/0x10c
[ 20.175940] __kmalloc+0xf4/0x2d2
[ 20.175966] sof_control_load+0x17c/0xaf4 [snd_sof]
[ 20.175986] soc_tplg_dapm_widget_elems_load+0xfa5/0x1758
[ 20.176005] snd_soc_tplg_component_load+0x309/0x5d7
[ 20.176032] snd_sof_load_topology+0x78/0x115 [snd_sof]
[ 20.176058] sof_pcm_probe+0xa4/0xd7 [snd_sof]
[ 20.176076] snd_soc_component_probe+0x3b/0x99
[ 20.176093] soc_probe_component+0x2a3/0x4fc
[ 20.176109] snd_soc_bind_card+0x83c/0xfe3
[ 20.176127] devm_snd_soc_register_card+0x48/0x83
[ 20.176145] platform_drv_probe+0x88/0xac
[ 20.176162] really_probe+0x1b2/0x4f1
[ 20.176179] driver_probe_device+0x98/0xd7
[ 20.176197] device_driver_attach+0x71/0x96
[ 20.176214] __driver_attach+0xda/0xe5
[ 20.176232] bus_for_each_dev+0xcc/0x102
[ 20.176249] bus_add_driver+0x1cb/0x2e3
[ 20.176267] driver_register+0xd7/0x19c
[ 20.176285] do_one_initcall+0x158/0x30c
[ 20.176302] do_init_module+0xe5/0x2dc
[ 20.176319] load_module+0x3d0b/0x411a
[ 20.176336] __se_sys_finit_module+0x13e/0x166
[ 20.176353] do_syscall_64+0x43/0x55
[ 20.176371] entry_SYSCALL_64_after_hwframe+0x44/0xa9

[ 20.176400] The buggy address belongs to the object at ffff88813f66aa00
which belongs to the cache kmalloc-128 of size 128
[ 20.176420] The buggy address is located 100 bytes inside of
128-byte region [ffff88813f66aa00, ffff88813f66aa80)
[ 20.176434] The buggy address belongs to the page:
[ 20.176457] page:0000000032124a7f refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x13f66a
[ 20.176475] head:0000000032124a7f order:1 compound_mapcount:0
[ 20.176493] flags: 0x8000000000010200(slab|head)
[ 20.176517] raw: 8000000000010200 dead000000000100 dead000000000122 ffff888100043680
[ 20.176539] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[ 20.176554] page dumped because: kasan: bad access detected

[ 20.176578] Memory state around the buggy address:
[ 20.176596] ffff88813f66a900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 fc
[ 20.176614] ffff88813f66a980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 20.176631] >ffff88813f66aa00: 00 00 00 00 00 00 00 00 00 00 00 00 04 fc fc fc
[ 20.176646] ^
[ 20.176664] ffff88813f66aa80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 20.176680] ffff88813f66ab00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 20.176694] ==================================================================