This patch fixes the following KASAN report:
[ 779.044746] BUG: KASAN: slab-out-of-bounds in string+0xab/0x180
[ 779.044750] Read of size 1 at addr
ffff88814f327968 by task trace-cmd/2812
[ 779.044756] CPU: 1 PID: 2812 Comm: trace-cmd Not tainted 5.1.0-rc1+ #62
[ 779.044760] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
[ 779.044761] Call Trace:
[ 779.044769] dump_stack+0x5b/0x90
[ 779.044775] ? string+0xab/0x180
[ 779.044781] print_address_description+0x6c/0x23c
[ 779.044787] ? string+0xab/0x180
[ 779.044792] ? string+0xab/0x180
[ 779.044797] kasan_report.cold.3+0x1a/0x32
[ 779.044803] ? string+0xab/0x180
[ 779.044809] string+0xab/0x180
[ 779.044816] ? widen_string+0x160/0x160
[ 779.044822] ? vsnprintf+0x5bf/0x7f0
[ 779.044829] vsnprintf+0x4e7/0x7f0
[ 779.044836] ? pointer+0x4a0/0x4a0
[ 779.044841] ? seq_buf_vprintf+0x79/0xc0
[ 779.044848] seq_buf_vprintf+0x62/0xc0
[ 779.044855] trace_seq_printf+0x113/0x210
[ 779.044861] ? trace_seq_puts+0x110/0x110
[ 779.044867] ? trace_raw_output_prep+0xd8/0x110
[ 779.044876] trace_raw_output_smb3_tcon_class+0x9f/0xc0
[ 779.044882] print_trace_line+0x377/0x890
[ 779.044888] ? tracing_buffers_read+0x300/0x300
[ 779.044893] ? ring_buffer_read+0x58/0x70
[ 779.044899] s_show+0x6e/0x140
[ 779.044906] seq_read+0x505/0x6a0
[ 779.044913] vfs_read+0xaf/0x1b0
[ 779.044919] ksys_read+0xa1/0x130
[ 779.044925] ? kernel_write+0xa0/0xa0
[ 779.044931] ? __do_page_fault+0x3d5/0x620
[ 779.044938] do_syscall_64+0x63/0x150
[ 779.044944] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 779.044949] RIP: 0033:0x7f62c2c2db31
[ 779.044955] Code: fe ff ff 48 8d 3d 17 9e 09 00 48 83 ec 08 e8 96 02
02 00 66 0f 1f 44 00 00 8b 05 fa fc 2c 00 48 63 ff 85 c0 75 13 31 c0
0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48
89
[ 779.044958] RSP: 002b:
00007ffd6e116678 EFLAGS:
00000246 ORIG_RAX:
0000000000000000
[ 779.044964] RAX:
ffffffffffffffda RBX:
0000560a38be9260 RCX:
00007f62c2c2db31
[ 779.044966] RDX:
0000000000002000 RSI:
00007ffd6e116710 RDI:
0000000000000003
[ 779.044966] RDX:
0000000000002000 RSI:
00007ffd6e116710 RDI:
0000000000000003
[ 779.044969] RBP:
00007f62c2ef5420 R08:
0000000000000000 R09:
0000000000000003
[ 779.044972] R10:
ffffffffffffffa8 R11:
0000000000000246 R12:
00007ffd6e116710
[ 779.044975] R13:
0000000000002000 R14:
0000000000000d68 R15:
0000000000002000
[ 779.044981] Allocated by task 1257:
[ 779.044987] __kasan_kmalloc.constprop.5+0xc1/0xd0
[ 779.044992] kmem_cache_alloc+0xad/0x1a0
[ 779.044997] getname_flags+0x6c/0x2a0
[ 779.045003] user_path_at_empty+0x1d/0x40
[ 779.045008] do_faccessat+0x12a/0x330
[ 779.045012] do_syscall_64+0x63/0x150
[ 779.045017] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 779.045019] Freed by task 1257:
[ 779.045023] __kasan_slab_free+0x12e/0x180
[ 779.045029] kmem_cache_free+0x85/0x1b0
[ 779.045034] filename_lookup.part.70+0x176/0x250
[ 779.045039] do_faccessat+0x12a/0x330
[ 779.045043] do_syscall_64+0x63/0x150
[ 779.045048] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 779.045052] The buggy address belongs to the object at
ffff88814f326600
which belongs to the cache names_cache of size 4096
[ 779.045057] The buggy address is located 872 bytes to the right of
4096-byte region [
ffff88814f326600,
ffff88814f327600)
[ 779.045058] The buggy address belongs to the page:
[ 779.045062] page:
ffffea00053cc800 count:1 mapcount:0 mapping:
ffff88815b191b40 index:0x0 compound_mapcount: 0
[ 779.045067] flags: 0x200000000010200(slab|head)
[ 779.045075] raw:
0200000000010200 dead000000000100 dead000000000200 ffff88815b191b40
[ 779.045081] raw:
0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[ 779.045083] page dumped because: kasan: bad access detected
[ 779.045085] Memory state around the buggy address:
[ 779.045089]
ffff88814f327800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 779.045093]
ffff88814f327880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 779.045097] >
ffff88814f327900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 779.045099] ^
[ 779.045103]
ffff88814f327980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 779.045107]
ffff88814f327a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 779.045109] ==================================================================
[ 779.045110] Disabling lock debugging due to kernel taint
Correctly assign tree name str for smb3_tcon event.
Signed-off-by: Paulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: Steve French <stfrench@microsoft.com>