Hi,
Am 2020-07-15 20:54, schrieb Chuck Lever:
> v5.4.40 does not have 31c9590ae468 and friends, but the claim is this
> one crashes?
To my knowledge 31c9590ae468 and friends are in v5.4.40.
> And v5.4.51 has those three and 89a3c9f5b9f0, which Pierre claims fixes
> the problem for him; but another commenter says v5.4.51 still crashes.
v5.4.51 still crashes for me (and afaik it does not have 89a3c9f5b9f0).
I applied 89a3c9f5b9f0 to the original v5.4.40 which helps mostly.
My krb5 etype is aes256-cts-hmac-sha1-96.
Below is the bug in the original v5.4.40 with KASAN enabled. It happened
immediately after mount of /home, no login neccessary:
[ 21.501730] ==================================================================
[ 21.501756] BUG: KASAN: slab-out-of-bounds in _copy_from_pages+0xe9/0x200 [sunrpc]
[ 21.501759] Write of size 64 at addr ffff8883bc9f3244 by task update-desktop-/1478
[ 21.501763] CPU: 0 PID: 1478 Comm: update-desktop- Tainted: G OE 5.4.0-40-generic #44
[ 21.501764] Hardware name: XXXXXXXXXXXXXXXXXXXXXX
[ 21.501765] Call Trace:
[ 21.501769] dump_stack+0x96/0xca
[ 21.501772] print_address_description.constprop.0+0x20/0x210
[ 21.501789] ? _copy_from_pages+0xe9/0x200 [sunrpc]
[ 21.501790] __kasan_report.cold+0x1b/0x41
[ 21.501806] ? _copy_from_pages+0xe9/0x200 [sunrpc]
[ 21.501807] kasan_report+0x12/0x20
[ 21.501809] check_memory_region+0x129/0x1b0
[ 21.501811] memcpy+0x38/0x50
[ 21.501825] _copy_from_pages+0xe9/0x200 [sunrpc]
[ 21.501839] ? call_decode+0x2fd/0x7e0 [sunrpc]
[ 21.501854] ? __rpc_execute+0x204/0xbd0 [sunrpc]
[ 21.501869] xdr_shrink_pagelen+0x198/0x3c0 [sunrpc]
[ 21.501871] ? trailing_symlink+0x6fe/0x810
[ 21.501886] xdr_align_pages+0x15f/0x580 [sunrpc]
[ 21.501904] ? decode_setattr+0x120/0x120 [nfsv4]
[ 21.501920] xdr_read_pages+0x44/0x290 [sunrpc]
[ 21.501935] ? __decode_op_hdr+0x29/0x430 [nfsv4]
[ 21.501949] nfs4_xdr_dec_readlink+0x238/0x390 [nfsv4]
[ 21.501963] ? nfs4_xdr_dec_read+0x3c0/0x3c0 [nfsv4]
[ 21.501966] ? __kasan_slab_free+0x14e/0x180
[ 21.501970] ? gss_validate+0x37e/0x610 [auth_rpcgss]
[ 21.501972] ? kasan_slab_free+0xe/0x10
[ 21.501985] ? nfs4_xdr_dec_read+0x3c0/0x3c0 [nfsv4]
[ 21.502001] rpcauth_unwrap_resp_decode+0xaa/0x100 [sunrpc]
[ 21.502005] gss_unwrap_resp+0x99d/0x1570 [auth_rpcgss]
[ 21.502009] ? gss_destroy_cred+0x460/0x460 [auth_rpcgss]
[ 21.502011] ? finish_task_switch+0x163/0x670
[ 21.502014] ? __switch_to_asm+0x34/0x70
[ 21.502017] ? gss_wrap_req+0x830/0x830 [auth_rpcgss]
[ 21.502020] ? prepare_to_wait+0xea/0x2b0
[ 21.502036] rpcauth_unwrap_resp+0xac/0x100 [sunrpc]
[ 21.502049] call_decode+0x454/0x7e0 [sunrpc]
[ 21.502063] ? rpc_decode_header+0x10a0/0x10a0 [sunrpc]
[ 21.502065] ? var_wake_function+0x140/0x140
[ 21.502078] ? call_transmit_status+0x31e/0x5d0 [sunrpc]
[ 21.502091] ? rpc_decode_header+0x10a0/0x10a0 [sunrpc]
[ 21.502106] __rpc_execute+0x204/0xbd0 [sunrpc]
[ 21.502119] ? xprt_wait_for_reply_request_def+0x170/0x170 [sunrpc]
[ 21.502134] ? rpc_exit+0xc0/0xc0 [sunrpc]
[ 21.502135] ? __kasan_check_read+0x11/0x20
[ 21.502137] ? wake_up_bit+0x42/0x50
[ 21.502151] rpc_execute+0x1a0/0x1f0 [sunrpc]
[ 21.502165] rpc_run_task+0x454/0x5e0 [sunrpc]
[ 21.502179] nfs4_call_sync_custom+0x12/0x70 [nfsv4]
[ 21.502192] nfs4_call_sync_sequence+0x143/0x1f0 [nfsv4]
[ 21.502194] ? __read_once_size_nocheck.constprop.0+0x10/0x10
[ 21.502207] ? nfs4_call_sync_custom+0x70/0x70 [nfsv4]
[ 21.502209] ? __kasan_check_read+0x11/0x20
[ 21.502211] ? rmqueue+0x397/0x2410
[ 21.502225] _nfs4_proc_readlink+0x1a6/0x250 [nfsv4]
[ 21.502238] ? _nfs4_proc_getdeviceinfo+0x350/0x350 [nfsv4]
[ 21.502254] nfs4_proc_readlink+0x101/0x2c0 [nfsv4]
[ 21.502268] ? nfs4_proc_link+0x1c0/0x1c0 [nfsv4]
[ 21.502271] ? add_to_page_cache_locked+0x20/0x20
[ 21.502285] nfs_symlink_filler+0xdc/0x190 [nfs]
[ 21.502287] do_read_cache_page+0x60e/0x1490
[ 21.502297] ? nfs4_do_lookup_revalidate+0x1a1/0x2d0 [nfs]
[ 21.502308] ? nfs_get_link+0x370/0x370 [nfs]
[ 21.502311] ? xas_load+0x23/0x250
[ 21.502312] ? pagecache_get_page+0x760/0x760
[ 21.502315] ? lockref_get_not_dead+0xe3/0x1c0
[ 21.502317] ? __kasan_check_write+0x14/0x20
[ 21.502318] ? lockref_get_not_dead+0xe3/0x1c0
[ 21.502320] ? __kasan_check_write+0x14/0x20
[ 21.502321] ? _raw_spin_lock+0x7b/0xd0
[ 21.502323] ? _raw_write_trylock+0x110/0x110
[ 21.502325] read_cache_page+0x4c/0x80
[ 21.502335] nfs_get_link+0x75/0x370 [nfs]
[ 21.502337] trailing_symlink+0x6fe/0x810
[ 21.502347] ? nfs_destroy_readpagecache+0x20/0x20 [nfs]
[ 21.502349] path_lookupat.isra.0+0x188/0x7d0
[ 21.502351] ? do_syscall_64+0x9f/0x3a0
[ 21.502353] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 21.502355] ? path_parentat.isra.0+0x110/0x110
[ 21.502357] ? stack_trace_save+0x94/0xc0
[ 21.502359] ? stack_trace_consume_entry+0x170/0x170
[ 21.502361] filename_lookup+0x185/0x3b0
[ 21.502362] ? nd_jump_link+0x1d0/0x1d0
[ 21.502364] ? kasan_slab_free+0xe/0x10
[ 21.502366] ? __kasan_check_read+0x11/0x20
[ 21.502367] ? __check_object_size+0x249/0x316
[ 21.502369] ? strncpy_from_user+0x80/0x290
[ 21.502370] ? kmem_cache_alloc+0x180/0x250
[ 21.502372] ? getname_flags+0x100/0x520
[ 21.502374] user_path_at_empty+0x3a/0x50
[ 21.502375] vfs_statx+0xca/0x150
[ 21.502377] ? vfs_statx_fd+0x90/0x90
[ 21.502379] ? __kasan_slab_free+0x14e/0x180
[ 21.502381] __do_sys_newstat+0x9a/0x100
[ 21.502382] ? cp_new_stat+0x5d0/0x5d0
[ 21.502384] ? __kasan_check_write+0x14/0x20
[ 21.502385] ? _raw_spin_lock_irq+0x82/0xe0
[ 21.502386] ? _raw_read_lock_irq+0x50/0x50
[ 21.502388] ? __blkcg_punt_bio_submit+0x1c0/0x1c0
[ 21.502390] ? __kasan_check_write+0x14/0x20
[ 21.502392] ? switch_fpu_return+0x13a/0x2d0
[ 21.502393] ? fpregs_mark_activate+0x150/0x150
[ 21.502395] __x64_sys_newstat+0x54/0x80
[ 21.502397] do_syscall_64+0x9f/0x3a0
[ 21.502398] ? prepare_exit_to_usermode+0xee/0x1a0
[ 21.502400] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 21.502402] RIP: 0033:0x7f9afc30049a
[ 21.502404] Code: 00 00 75 05 48 83 c4 18 c3 e8 f2 24 02 00 66 90 f3 0f 1e fa 41 89 f8 48 89 f7 48 89 d6 41 83 f8 01 77 2d b8 04 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 8b 15 c1 a9 0d 00 f7
[ 21.502405] RSP: 002b:00007ffe7cd464c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000004
[ 21.502407] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f9afc30049a
[ 21.502408] RDX: 00007ffe7cd464d0 RSI: 00007ffe7cd464d0 RDI: 000055c9330705f0
[ 21.502409] RBP: 000055c9330705f0 R08: 0000000000000001 R09: 0000000000000001
[ 21.502410] R10: 0000000000000017 R11: 0000000000000246 R12: 000055c933074de3
[ 21.502410] R13: 000055c93306e1a0 R14: 000055c93306c940 R15: 000055c93306c990
[ 21.502414] Allocated by task 1478:
[ 21.502416] save_stack+0x23/0x90
[ 21.502418] __kasan_kmalloc.constprop.0+0xcf/0xe0
[ 21.502419] kasan_slab_alloc+0xe/0x10
[ 21.502420] kmem_cache_alloc+0xd7/0x250
[ 21.502422] mempool_alloc_slab+0x17/0x20
[ 21.502424] mempool_alloc+0x126/0x330
[ 21.502439] rpc_malloc+0x1f2/0x270 [sunrpc]
[ 21.502452] call_allocate+0x3b9/0x9d0 [sunrpc]
[ 21.502467] __rpc_execute+0x204/0xbd0 [sunrpc]
[ 21.502480] rpc_execute+0x1a0/0x1f0 [sunrpc]
[ 21.502493] rpc_run_task+0x454/0x5e0 [sunrpc]
[ 21.502507] nfs4_call_sync_custom+0x12/0x70 [nfsv4]
[ 21.502520] nfs4_call_sync_sequence+0x143/0x1f0 [nfsv4]
[ 21.502533] _nfs4_proc_readlink+0x1a6/0x250 [nfsv4]
[ 21.502546] nfs4_proc_readlink+0x101/0x2c0 [nfsv4]
[ 21.502558] nfs_symlink_filler+0xdc/0x190 [nfs]
[ 21.502560] do_read_cache_page+0x60e/0x1490
[ 21.502561] read_cache_page+0x4c/0x80
[ 21.502571] nfs_get_link+0x75/0x370 [nfs]
[ 21.502572] trailing_symlink+0x6fe/0x810
[ 21.502574] path_lookupat.isra.0+0x188/0x7d0
[ 21.502575] filename_lookup+0x185/0x3b0
[ 21.502576] user_path_at_empty+0x3a/0x50
[ 21.502578] vfs_statx+0xca/0x150
[ 21.502579] __do_sys_newstat+0x9a/0x100
[ 21.502581] __x64_sys_newstat+0x54/0x80
[ 21.502582] do_syscall_64+0x9f/0x3a0
[ 21.502584] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 21.502585] Freed by task 0:
[ 21.502586] (stack is not available)
[ 21.502589] The buggy address belongs to the object at ffff8883bc9f2a80
which belongs to the cache rpc_buffers of size 2048
[ 21.502591] The buggy address is located 1988 bytes inside of
2048-byte region [ffff8883bc9f2a80, ffff8883bc9f3280)
[ 21.502592] The buggy address belongs to the page:
[ 21.502595] page:ffffea000ef27c00 refcount:1 mapcount:0 mapping:ffff8883bf61e600 index:0x0 compound_mapcount: 0
[ 21.502597] flags: 0x17ffffc0010200(slab|head)
[ 21.502600] raw: 0017ffffc0010200 dead000000000100 dead000000000122 ffff8883bf61e600
[ 21.502602] raw: 0000000000000000 00000000800f000f 00000001ffffffff 0000000000000000
[ 21.502603] page dumped because: kasan: bad access detected
[ 21.502605] Memory state around the buggy address:
[ 21.502607] ffff8883bc9f3180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 21.502608] ffff8883bc9f3200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 21.502610] >ffff8883bc9f3280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 21.502611] ^
[ 21.502612] ffff8883bc9f3300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 21.502614] ffff8883bc9f3380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 21.502615] ==================================================================
[ 21.502616] Disabling lock debugging due to kernel taint
Best Regards
--
Pierre Sauter
Studentenwerk München
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