In the Linux kernel, the following vulnerability has been resolved: tpm: do not start chip while suspended Checking TPM_CHIP_FLAG_SUSPENDED after the call to tpm_find_get_ops() can lead to a spurious tpm_chip_start() call: [35985.503771] i2c i2c-1: Transfer while suspended [35985.503796] WARNING: CPU: 0 PID: 74 at drivers/i2c/i2c-core.h:56 __i2c_transfer+0xbe/0x810 [35985.503802] Modules linked in: [35985.503808] CPU: 0 UID: 0 PID: 74 Comm: hwrng Tainted: G W 6.13.0-next-20250203-00005-gfa0cb5642941 #19 9c3d7f78192f2d38e32010ac9c90fdc71109ef6f [35985.503814] Tainted: [W]=WARN [35985.503817] Hardware name: Google Morphius/Morphius, BIOS Google_Morphius.13434.858.0 10/26/2023 [35985.503819] RIP: 0010:__i2c_transfer+0xbe/0x810 [35985.503825] Code: 30 01 00 00 4c 89 f7 e8 40 fe d8 ff 48 8b 93 80 01 00 00 48 85 d2 75 03 49 8b 16 48 c7 c7 0a fb 7c a7 48 89 c6 e8 32 ad b0 fe <0f> 0b b8 94 ff ff ff e9 33 04 00 00 be 02 00 00 00 83 fd 02 0f 5 [35985.503828] RSP: 0018:ffffa106c0333d30 EFLAGS: 00010246 [35985.503833] RAX: 074ba64aa20f7000 RBX: ffff8aa4c1167120 RCX: 0000000000000000 [35985.503836] RDX: 0000000000000000 RSI: ffffffffa77ab0e4 RDI: 0000000000000001 [35985.503838] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 [35985.503841] R10: 0000000000000004 R11: 00000001000313d5 R12: ffff8aa4c10f1820 [35985.503843] R13: ffff8aa4c0e243c0 R14: ffff8aa4c1167250 R15: ffff8aa4c1167120 [35985.503846] FS: 0000000000000000(0000) GS:ffff8aa4eae00000(0000) knlGS:0000000000000000 [35985.503849] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [35985.503852] CR2: 00007fab0aaf1000 CR3: 0000000105328000 CR4: 00000000003506f0 [35985.503855] Call Trace: [35985.503859] <TASK> [35985.503863] ? __warn+0xd4/0x260 [35985.503868] ? __i2c_transfer+0xbe/0x810 [35985.503874] ? report_bug+0xf3/0x210 [35985.503882] ? handle_bug+0x63/0xb0 [35985.503887] ? exc_invalid_op+0x16/0x50 [35985.503892] ? asm_exc_invalid_op+0x16/0x20 [35985.503904] ? __i2c_transfer+0xbe/0x810 [35985.503913] tpm_cr50_i2c_transfer_message+0x24/0xf0 [35985.503920] tpm_cr50_i2c_read+0x8e/0x120 [35985.503928] tpm_cr50_request_locality+0x75/0x170 [35985.503935] tpm_chip_start+0x116/0x160 [35985.503942] tpm_try_get_ops+0x57/0x90 [35985.503948] tpm_find_get_ops+0x26/0xd0 [35985.503955] tpm_get_random+0x2d/0x80 Don't move forward with tpm_chip_start() inside tpm_try_get_ops(), unless TPM_CHIP_FLAG_SUSPENDED is not set. tpm_find_get_ops() will return NULL in such a failure case.
tpm: do not start chip while suspended