Path printed twice, separated by numerous empty linesusing bpf_d_path(&file->f_path , d_path_buf , MAX_STR);

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#define MAX_STR  128
char d_path_buf[MAX_STR] = {};
bpf_d_path(&file->f_path , d_path_buf , MAX_STR);

I am using bpf_d_path helper function to extract full path. path "/proc/4581/cmdline" is printed twice, separated by numerous empty lines.

return value shows here that bpf_d_path wrote 19 char but when i printed all char one by one it shows path then empty spaces and the path again (path___path).

kernel 6.5.0-14-generic

                                                                    char (loop value)   
            node-1346    [005] ...11 28932.918673: bpf_trace_printk:  /     0
            node-1346    [005] ...11 28932.918674: bpf_trace_printk:  p     1
            node-1346    [005] ...11 28932.918675: bpf_trace_printk:  r     2
            node-1346    [005] ...11 28932.918676: bpf_trace_printk:  o     3
            node-1346    [005] ...11 28932.918677: bpf_trace_printk:  c     4
            node-1346    [005] ...11 28932.918677: bpf_trace_printk:  /     5
            node-1346    [005] ...11 28932.918678: bpf_trace_printk:  6     6
            node-1346    [005] ...11 28932.918680: bpf_trace_printk:  6     7
            node-1346    [005] ...11 28932.918680: bpf_trace_printk:  6     8
            node-1346    [005] ...11 28932.918681: bpf_trace_printk:  2     9
            node-1346    [005] ...11 28932.918682: bpf_trace_printk:  /     10
            node-1346    [005] ...11 28932.918683: bpf_trace_printk:  c     11
            node-1346    [005] ...11 28932.918684: bpf_trace_printk:  m     12
            node-1346    [005] ...11 28932.918685: bpf_trace_printk:  d     13
            node-1346    [005] ...11 28932.918685: bpf_trace_printk:  l     14
            node-1346    [005] ...11 28932.918686: bpf_trace_printk:  i     15
            node-1346    [005] ...11 28932.918687: bpf_trace_printk:  n     16
            node-1346    [005] ...11 28932.918688: bpf_trace_printk:  e     17
            node-1346    [005] ...11 28932.918689: bpf_trace_printk:
            node-1346    [005] ...11 28932.918690: bpf_trace_printk:
            node-1346    [005] ...11 28932.918690: bpf_trace_printk:
            node-1346    [005] ...11 28932.918691: bpf_trace_printk:
            node-1346    [005] ...11 28932.918692: bpf_trace_printk:
            node-1346    [005] ...11 28932.918693: bpf_trace_printk:
            node-1346    [005] ...11 28932.918694: bpf_trace_printk:
            node-1346    [005] ...11 28932.918694: bpf_trace_printk:
            node-1346    [005] ...11 28932.918696: bpf_trace_printk:
            node-1346    [005] ...11 28932.918697: bpf_trace_printk:
            node-1346    [005] ...11 28932.918697: bpf_trace_printk:
            node-1346    [005] ...11 28932.918698: bpf_trace_printk:
            node-1346    [005] ...11 28932.918698: bpf_trace_printk:
            node-1346    [005] ...11 28932.918700: bpf_trace_printk:
            node-1346    [005] ...11 28932.918700: bpf_trace_printk:
            node-1346    [005] ...11 28932.918701: bpf_trace_printk:
            node-1346    [005] ...11 28932.918702: bpf_trace_printk:
            node-1346    [005] ...11 28932.918703: bpf_trace_printk:
            node-1346    [005] ...11 28932.918704: bpf_trace_printk:
            node-1346    [005] ...11 28932.918705: bpf_trace_printk:
            node-1346    [005] ...11 28932.918706: bpf_trace_printk:
            node-1346    [005] ...11 28932.918706: bpf_trace_printk:
            node-1346    [005] ...11 28932.918707: bpf_trace_printk:
            node-1346    [005] ...11 28932.918708: bpf_trace_printk:
            node-1346    [005] ...11 28932.918709: bpf_trace_printk:
            node-1346    [005] ...11 28932.918710: bpf_trace_printk:
            node-1346    [005] ...11 28932.918710: bpf_trace_printk:
            node-1346    [005] ...11 28932.918711: bpf_trace_printk:
            node-1346    [005] ...11 28932.918712: bpf_trace_printk:
            node-1346    [005] ...11 28932.918713: bpf_trace_printk:
            node-1346    [005] ...11 28932.918714: bpf_trace_printk:
            node-1346    [005] ...11 28932.918714: bpf_trace_printk:
            node-1346    [005] ...11 28932.918715: bpf_trace_printk:
            node-1346    [005] ...11 28932.918716: bpf_trace_printk:
            node-1346    [005] ...11 28932.918717: bpf_trace_printk:
            node-1346    [005] ...11 28932.918718: bpf_trace_printk:
            node-1346    [005] ...11 28932.918718: bpf_trace_printk:
            node-1346    [005] ...11 28932.918719: bpf_trace_printk:
            node-1346    [005] ...11 28932.918720: bpf_trace_printk:
            node-1346    [005] ...11 28932.918721: bpf_trace_printk:
            node-1346    [005] ...11 28932.918722: bpf_trace_printk:
            node-1346    [005] ...11 28932.918722: bpf_trace_printk:
            node-1346    [005] ...11 28932.918723: bpf_trace_printk:
            node-1346    [005] ...11 28932.918725: bpf_trace_printk:
            node-1346    [005] ...11 28932.918726: bpf_trace_printk:
            node-1346    [005] ...11 28932.918726: bpf_trace_printk:
            node-1346    [005] ...11 28932.918727: bpf_trace_printk:
            node-1346    [005] ...11 28932.918728: bpf_trace_printk:
            node-1346    [005] ...11 28932.918729: bpf_trace_printk:
            node-1346    [005] ...11 28932.918730: bpf_trace_printk:
            node-1346    [005] ...11 28932.918731: bpf_trace_printk:
            node-1346    [005] ...11 28932.918731: bpf_trace_printk:
            node-1346    [005] ...11 28932.918732: bpf_trace_printk:
            node-1346    [005] ...11 28932.918732: bpf_trace_printk:
            node-1346    [005] ...11 28932.918734: bpf_trace_printk:
            node-1346    [005] ...11 28932.918735: bpf_trace_printk:
            node-1346    [005] ...11 28932.918736: bpf_trace_printk:
            node-1346    [005] ...11 28932.918736: bpf_trace_printk:
            node-1346    [005] ...11 28932.918737: bpf_trace_printk:
            node-1346    [005] ...11 28932.918738: bpf_trace_printk:
            node-1346    [005] ...11 28932.918738: bpf_trace_printk:
            node-1346    [005] ...11 28932.918739: bpf_trace_printk:
            node-1346    [005] ...11 28932.918740: bpf_trace_printk:
            node-1346    [005] ...11 28932.918740: bpf_trace_printk:
            node-1346    [005] ...11 28932.918741: bpf_trace_printk:
            node-1346    [005] ...11 28932.918742: bpf_trace_printk:
            node-1346    [005] ...11 28932.918743: bpf_trace_printk:
            node-1346    [005] ...11 28932.918744: bpf_trace_printk:
            node-1346    [005] ...11 28932.918744: bpf_trace_printk:
            node-1346    [005] ...11 28932.918745: bpf_trace_printk:
            node-1346    [005] ...11 28932.918746: bpf_trace_printk:
            node-1346    [005] ...11 28932.918747: bpf_trace_printk:
            node-1346    [005] ...11 28932.918748: bpf_trace_printk:
            node-1346    [005] ...11 28932.918749: bpf_trace_printk:
            node-1346    [005] ...11 28932.918749: bpf_trace_printk:
            node-1346    [005] ...11 28932.918750: bpf_trace_printk:
            node-1346    [005] ...11 28932.918751: bpf_trace_printk:
            node-1346    [005] ...11 28932.918752: bpf_trace_printk:
            node-1346    [005] ...11 28932.918753: bpf_trace_printk:
            node-1346    [005] ...11 28932.918754: bpf_trace_printk:
            node-1346    [005] ...11 28932.918755: bpf_trace_printk:
            node-1346    [005] ...11 28932.918756: bpf_trace_printk:
            node-1346    [005] ...11 28932.918756: bpf_trace_printk:
            node-1346    [005] ...11 28932.918757: bpf_trace_printk:
            node-1346    [005] ...11 28932.918758: bpf_trace_printk:
            node-1346    [005] ...11 28932.918759: bpf_trace_printk:
            node-1346    [005] ...11 28932.918760: bpf_trace_printk:
            node-1346    [005] ...11 28932.918760: bpf_trace_printk:
            node-1346    [005] ...11 28932.918761: bpf_trace_printk:
            node-1346    [005] ...11 28932.918762: bpf_trace_printk:
            node-1346    [005] ...11 28932.918763: bpf_trace_printk:
            node-1346    [005] ...11 28932.918764: bpf_trace_printk:  /     109
            node-1346    [005] ...11 28932.918765: bpf_trace_printk:  p     110
            node-1346    [005] ...11 28932.918766: bpf_trace_printk:  r     111
            node-1346    [005] ...11 28932.918766: bpf_trace_printk:  o     112
            node-1346    [005] ...11 28932.918768: bpf_trace_printk:  c     113
            node-1346    [005] ...11 28932.918768: bpf_trace_printk:  /     114
            node-1346    [005] ...11 28932.918769: bpf_trace_printk:  6     115
            node-1346    [005] ...11 28932.918770: bpf_trace_printk:  6     116
            node-1346    [005] ...11 28932.918770: bpf_trace_printk:  6     117
            node-1346    [005] ...11 28932.918771: bpf_trace_printk:  2     118
            node-1346    [005] ...11 28932.918773: bpf_trace_printk:  /     119
            node-1346    [005] ...11 28932.918774: bpf_trace_printk:  c     120
            node-1346    [005] ...11 28932.918774: bpf_trace_printk:  m     121
            node-1346    [005] ...11 28932.918775: bpf_trace_printk:  d     122
            node-1346    [005] ...11 28932.918776: bpf_trace_printk:  l     123
            node-1346    [005] ...11 28932.918776: bpf_trace_printk:  i     124
            node-1346    [005] ...11 28932.918777: bpf_trace_printk:  n     125
            node-1346    [005] ...11 28932.918778: bpf_trace_printk:  e     126
            node-1346    [005] ...11 28932.918778: bpf_trace_printk:

Not sure what causing this. if any one have anything please let me know

I was expecting simple full path

0

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