xe: Fix CFI violation when accessing sysfs files #21
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When an attribute is created with sysfs_create_files(), callbacks is set to kobj_attr_show() and kobj_attr_store() respectively. When CFI is strictly enforced, attribute show and store callbacks needs to be the same type as the callbacks in 'struct kobj_attribute'.
As the show/store function of some of the gt attributes are not matching the callback signature, CFI violation is seen.
CFI failure seen while accessing sysfs files under following directory /sys/class/drm/card0/device/tile0/gt*/gtidle/*
/sys/class/drm/card0/device/tile0/gt1/freq0/*
[ 2599.618075] RIP: 0010:__cfi_cur_freq_show+0xd/0x10 [xe] [ 2599.624452] Code: 44 c1 44 89 fa e8 03 95 39 f2 48 98 5b 41 5e 41 5f 5d c3 c9 [ 2599.646638] RSP: 0018:ffffbe438ead7d10 EFLAGS: 00010286 [ 2599.652823] RAX: ffff9f7d8b3845d8 RBX: ffff9f7dee8c95d8 RCX: 0000000000000000 [ 2599.661246] RDX: ffff9f7e6f439000 RSI: ffffffffc13ada30 RDI: ffff9f7d975d4b00 [ 2599.669669] RBP: ffffbe438ead7d18 R08: 0000000000001000 R09: ffff9f7e6f439000 [ 2599.678092] R10: 00000000e07304a6 R11: ffffffffc1241ca0 R12: ffffffffb4836ea0 [ 2599.688435] R13: ffff9f7e45fb1180 R14: ffff9f7d975d4b00 R15: ffff9f7e6f439000 [ 2599.696860] FS: 000076b02b66cfc0(0000) GS:ffff9f80ef400000(0000) knlGS:00000 [ 2599.706412] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2599.713196] CR2: 00005f80d94641a9 CR3: 00000001e44ec006 CR4: 0000000100f72ef0 [ 2599.721618] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2599.730041] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400 [ 2599.738464] PKRU: 55555554
[ 2599.741655] Call Trace:
[ 2599.744541]
[ 2599.747017] ? __die_body+0x69/0xb0
[ 2599.751151] ? die+0xa9/0xd0
[ 2599.754548] ? do_trap+0x89/0x160
[ 2599.758476] ? __cfi_cur_freq_show+0xd/0x10 [xe b37985c94829727668bd7c5b33c1] [ 2599.768315] ? handle_invalid_op+0x69/0x90
[ 2599.773167] ? __cfi_cur_freq_show+0xd/0x10 [xe b37985c94829727668bd7c5b33c1] [ 2599.783010] ? exc_invalid_op+0x36/0x60
[ 2599.787552] ? fred_hwexc+0x123/0x1a0
[ 2599.791873] ? fred_entry_from_kernel+0x7b/0xd0
[ 2599.797219] ? asm_fred_entrypoint_kernel+0x45/0x70 [ 2599.802976] ? act_freq_show+0x70/0x70 [xe b37985c94829727668bd7c5b33c1d9998] [ 2599.812301] ? __cfi_cur_freq_show+0xd/0x10 [xe b37985c94829727668bd7c5b33c1] [ 2599.822137] ? __kmalloc_node_noprof+0x1f3/0x420 [ 2599.827594] ? __kvmalloc_node_noprof+0xcb/0x180 [ 2599.833045] ? kobj_attr_show+0x22/0x40
[ 2599.837571] sysfs_kf_seq_show+0xa8/0x110
[ 2599.842302] kernfs_seq_show+0x38/0x50
Changed the gt attribute callback function to the show/store attribute callback functions in struct kobj_attribute.
Tracked-On: CHRMOS-17893