KMSAN: uninit-value in aes

KMSAN: uninit-value in aes_encrypt (4)
Status: upstream: reported C repro on 2020/09/10 14:09
Reported-by: syzbot+828dfc12440b4f6f305d@syzkaller.appspotmail.com
First crash: 223d, last: 220d

similar bugs (3):
Kernel	Title	Repro	Count	Last	Reported	Patched	Status
upstream	KMSAN: uninit-value in aes_encrypt	C	2	1108d	1108d	0/22	closed as invalid on 2018/06/27 14:58
upstream	KMSAN: uninit-value in aes_encrypt (2)	C	52	515d	544d	0/22	closed as dup on 2019/11/19 02:55
upstream	KMSAN: uninit-value in aes_encrypt (3)	C	2	276d	277d	0/22	closed as invalid on 2020/07/22 14:12

Patch testing requests:
Created	Duration	User	Patch	Repo	Result
2020/09/14 11:34	14m	himadrispandya@gmail.com		https://github.com/google/kmsan.git master	report log

Sample crash report:

=====================================================
BUG: KMSAN: uninit-value in subshift lib/crypto/aes.c:149 [inline]
BUG: KMSAN: uninit-value in aes_encrypt+0x12c5/0x1bc0 lib/crypto/aes.c:282
CPU: 1 PID: 8502 Comm: syz-executor773 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 subshift lib/crypto/aes.c:149 [inline]
 aes_encrypt+0x12c5/0x1bc0 lib/crypto/aes.c:282
 aesti_encrypt+0xe8/0x130 crypto/aes_ti.c:31
 cipher_crypt_one crypto/cipher.c:75 [inline]
 crypto_cipher_encrypt_one+0x1e2/0x3a0 crypto/cipher.c:82
 crypto_cbcmac_digest_update+0x3e3/0x560 crypto/ccm.c:830
 crypto_shash_update+0x455/0x5a0 crypto/shash.c:119
 shash_ahash_finup+0x20b/0x7a0 crypto/shash.c:291
 shash_async_finup+0xbb/0x110 crypto/shash.c:306
 crypto_ahash_op+0x1c3/0x770 crypto/ahash.c:370
 crypto_ahash_finup+0x8c/0xb0 crypto/ahash.c:395
 crypto_ccm_auth+0x16b6/0x1780 crypto/ccm.c:221
 crypto_ccm_encrypt+0x285/0x850 crypto/ccm.c:300
 crypto_aead_encrypt+0x107/0x190 crypto/aead.c:94
 tls_do_encryption net/tls/tls_sw.c:528 [inline]
 tls_push_record+0x3cb9/0x4fc0 net/tls/tls_sw.c:762
 bpf_exec_tx_verdict+0x195a/0x29e0 net/tls/tls_sw.c:802
 tls_sw_do_sendpage+0x138a/0x1e30 net/tls/tls_sw.c:1213
 tls_sw_sendpage+0x1da/0x250 net/tls/tls_sw.c:1277
 inet_sendpage+0x1dc/0x2f0 net/ipv4/af_inet.c:828
 kernel_sendpage net/socket.c:3642 [inline]
 sock_sendpage+0x1dc/0x2b0 net/socket.c:945
 pipe_to_sendpage+0x3f4/0x530 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x5e3/0xff0 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0x2727/0x39e0 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice+0x323/0x500 fs/splice.c:1401
 __x64_sys_splice+0x6e/0x90 fs/splice.c:1401
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x446a29
Code: Bad RIP value.
RSP: 002b:00007f11fb607d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 0000000000446a29
RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006dbc40 R08: 00080000fffffffc R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c
R13: 0000000020000680 R14: 00000000004ae948 R15: 20c49ba5e353f7cf

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 __crypto_xor+0x251/0x1610 crypto/algapi.c:1000
 crypto_xor include/crypto/algapi.h:152 [inline]
 crypto_cbcmac_digest_update+0x2b8/0x560 crypto/ccm.c:824
 crypto_shash_update+0x455/0x5a0 crypto/shash.c:119
 shash_ahash_finup+0x20b/0x7a0 crypto/shash.c:291
 shash_async_finup+0xbb/0x110 crypto/shash.c:306
 crypto_ahash_op+0x1c3/0x770 crypto/ahash.c:370
 crypto_ahash_finup+0x8c/0xb0 crypto/ahash.c:395
 crypto_ccm_auth+0x16b6/0x1780 crypto/ccm.c:221
 crypto_ccm_encrypt+0x285/0x850 crypto/ccm.c:300
 crypto_aead_encrypt+0x107/0x190 crypto/aead.c:94
 tls_do_encryption net/tls/tls_sw.c:528 [inline]
 tls_push_record+0x3cb9/0x4fc0 net/tls/tls_sw.c:762
 bpf_exec_tx_verdict+0x195a/0x29e0 net/tls/tls_sw.c:802
 tls_sw_do_sendpage+0x138a/0x1e30 net/tls/tls_sw.c:1213
 tls_sw_sendpage+0x1da/0x250 net/tls/tls_sw.c:1277
 inet_sendpage+0x1dc/0x2f0 net/ipv4/af_inet.c:828
 kernel_sendpage net/socket.c:3642 [inline]
 sock_sendpage+0x1dc/0x2b0 net/socket.c:945
 pipe_to_sendpage+0x3f4/0x530 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x5e3/0xff0 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0x2727/0x39e0 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice+0x323/0x500 fs/splice.c:1401
 __x64_sys_splice+0x6e/0x90 fs/splice.c:1401
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:269 [inline]
 kmsan_alloc_page+0xc5/0x1a0 mm/kmsan/kmsan_shadow.c:293
 __alloc_pages_nodemask+0xdf0/0x1030 mm/page_alloc.c:4889
 alloc_pages_current+0x685/0xb50 mm/mempolicy.c:2292
 alloc_pages include/linux/gfp.h:545 [inline]
 skb_page_frag_refill+0x540/0x780 net/core/sock.c:2487
 sk_page_frag_refill+0xa3/0x3b0 net/core/sock.c:2507
 sk_msg_alloc+0x26e/0x1340 net/core/skmsg.c:38
 tls_alloc_encrypted_msg net/tls/tls_sw.c:289 [inline]
 tls_sw_do_sendpage+0xb0d/0x1e30 net/tls/tls_sw.c:1191
 tls_sw_sendpage+0x1da/0x250 net/tls/tls_sw.c:1277
 inet_sendpage+0x1dc/0x2f0 net/ipv4/af_inet.c:828
 kernel_sendpage net/socket.c:3642 [inline]
 sock_sendpage+0x1dc/0x2b0 net/socket.c:945
 pipe_to_sendpage+0x3f4/0x530 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x5e3/0xff0 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 do_splice+0x2727/0x39e0 fs/splice.c:1144
 __do_sys_splice fs/splice.c:1419 [inline]
 __se_sys_splice+0x323/0x500 fs/splice.c:1401
 __x64_sys_splice+0x6e/0x90 fs/splice.c:1401
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
=====================================================

Crashes (3):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro
ci-upstream-kmsan-gce	2020/09/12 10:57	https://github.com/google/kmsan.git master	3b3ea602	79fb24e2	.config	log	report	syz	C
ci-upstream-kmsan-gce	2020/09/10 09:23	https://github.com/google/kmsan.git master	3b3ea602	409809d8	.config	log	report	syz	C
ci-upstream-kmsan-gce	2020/09/10 05:25	https://github.com/google/kmsan.git master	3b3ea602	409809d8	.config	log	report