Hi Herbert, here is a reliably producable bug that I triggered while educating my libkcapi about AIO support. [70129.671557] page:ffffea0001361d80 count:0 mapcount:0 mapping: (null) index:0x0 [70129.671560] flags: 0x1ffffc00000000() [70129.671562] page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) [70129.671581] ------------[ cut here ]------------ [70129.671599] kernel BUG at include/linux/mm.h:420! [70129.671612] invalid opcode: 0000 [#2] SMP [70129.671623] Modules linked in: serpent_avx2 serpent_avx_x86_64 serpent_sse2_x86_64 serpent_generic loop crypto_user vhost_net vhost macvtap macvlan rfcomm xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 tun ip6t_REJECT nf_reject_ipv6 ip6t_rpfilter xt_conntrack ip_set nfnetlink ebtable_nat ebtable_broute bridge stp llc ip6table_security ip6table_mangle ip6table_raw ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 iptable_security iptable_mangle iptable_raw iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack ebtable_filter ebtables ip6table_filter ip6_tables bnep nls_utf8 hfsplus intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel brcmfmac kvm joydev iTCO_wdt iTCO_vendor_support applesmc irqbypass input_polldev brcmutil intel_cstate intel_uncore cfg80211 [70129.671875] btusb intel_rapl_perf snd_hda_codec_hdmi snd_hda_codec_cirrus snd_hda_codec_generic btrtl btbcm snd_hda_intel snd_hda_codec btintel bluetooth snd_hda_core snd_hwdep mmc_core snd_seq i2c_i801 intel_pch_thermal snd_seq_device thunderbolt snd_pcm rfkill bcm5974 snd_timer mei_me snd lpc_ich mei shpchp dw_dmac_pci soundcore spi_pxa2xx_pci acpi_als kfifo_buf industrialio spi_pxa2xx_platform sbs apple_bl tpm_tis sbshc tpm nfsd auth_rpcgss binfmt_misc nfs_acl lockd grace sunrpc dm_crypt hid_apple i915 crct10dif_pclmul crc32_pclmul crc32c_intel i2c_algo_bit drm_kms_helper uas usb_storage ghash_clmulni_intel drm fjes video [70129.672075] CPU: 2 PID: 24751 Comm: kcapi Tainted: G D 4.7.2-201.fc24.x86_64 #1 [70129.672095] Hardware name: Apple Inc. MacBookPro12,1/Mac-E43C1C25D4880AD6, BIOS MBP121.88Z.0167.B17.1606231721 06/23/2016 [70129.672120] task: ffff8801f2f53d00 ti: ffff88004f5c4000 task.ti: ffff88004f5c4000 [70129.672138] RIP: 0010:[<ffffffff81398811>] [<ffffffff81398811>] skcipher_pull_sgl+0x171/0x180 [70129.672163] RSP: 0018:ffff88004f5c7d38 EFLAGS: 00010246 [70129.672176] RAX: 000000000000003e RBX: ffff880228ae1018 RCX: 0000000000000006 [70129.672193] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88046ec8e060 [70129.672210] RBP: ffff88004f5c7d80 R08: 0000000000000922 R09: 0000000000000005 [70129.672227] R10: ffff8803fc90efb0 R11: ffffffff81f3edad R12: 0000000000000001 [70129.672244] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88044a671800 [70129.672262] FS: 00007f99962aa700(0000) GS:ffff88046ec80000(0000) knlGS: 0000000000000000 [70129.672281] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [70129.672296] CR2: 000000000170e1d8 CR3: 00000000250b0000 CR4: 00000000003406e0 [70129.672313] Stack: [70129.672318] ffff88044a677800 ffff8803fc90e1d0 ffff8803fc90e0b0 ffff8803fc90e1d0 [70129.672340] ffff88044a677ac8 ffff88044a671800 ffff88044a677800 ffff88044a4a6ba8 [70129.672361] ffff88020f5ae900 ffff88004f5c7db0 ffffffff8139889a ffff88044a677ac8 [70129.672382] Call Trace: [70129.672390] [<ffffffff8139889a>] skcipher_sock_destruct+0x7a/0xc0 [70129.672406] [<ffffffff816b2746>] __sk_destruct+0x26/0x140 [70129.672420] [<ffffffff816b42a0>] sk_destruct+0x20/0x30 [70129.672434] [<ffffffff816b42f3>] __sk_free+0x43/0xa0 [70129.672447] [<ffffffff816b4368>] sk_free+0x18/0x20 [70129.672460] [<ffffffff81397963>] af_alg_release+0x23/0x30 [70129.672474] [<ffffffff816ad79f>] sock_release+0x1f/0x80 [70129.672488] [<ffffffff816ad812>] sock_close+0x12/0x20 [70129.672502] [<ffffffff812481df>] __fput+0xdf/0x1f0 [70129.672514] [<ffffffff8124832e>] ____fput+0xe/0x10 [70129.672527] [<ffffffff810bd923>] task_work_run+0x83/0xb0 [70129.672542] [<ffffffff81003342>] exit_to_usermode_loop+0xc2/0xd0 [70129.672557] [<ffffffff81003ce1>] syscall_return_slowpath+0xa1/0xb0 [70129.672574] [<ffffffff817eb8fa>] entry_SYSCALL_64_fastpath+0xa2/0xa4 [70129.672589] Code: 00 00 00 75 08 41 c6 87 fd 02 00 00 00 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c6 68 46 a1 81 48 89 c7 e8 1f e7 e4 ff <0f> 0b 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 [70129.672692] RIP [<ffffffff81398811>] skcipher_pull_sgl+0x171/0x180 [70129.672709] RSP <ffff88004f5c7d38> [70129.672726] ---[ end trace e16e0f71a7a79252 ]--- Ciao Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
