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Read whole line in yes_or_no

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Do not stop after 79 characters. Read the complete line to avoid
arbitrary limitations.

Proof of Concept:

```
cat > passwd-poc << EOF
root❌0:0:root:/root:/bin/bash
root❌0:0:root:/root:/bin/bash
root❌0:0:root:/root:/bin/bash
EOF
python -c "print(80*'y')" | pwck passwd-poc
```

Two lines should still be within the file because we agreed only once
to remove a duplicated line.

Signed-off-by: Samanta Navarro <ferivoz@riseup.net>
Reviewed-by: Alejandro Colomar <alx@kernel.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
This commit is contained in:
Samanta Navarro 2023-01-27 11:53:57 +00:00 committed by Serge Hallyn
parent c80788a3ac
commit 0c83b98105
1 changed files with 8 additions and 5 deletions
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13
libmisc/yesno.c
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@ -28,7 +28,8 @@
*/ */
bool yes_or_no (bool read_only) bool yes_or_no (bool read_only)
{ {
char buf[80]; int c;
bool result;
/* /*
* In read-only mode all questions are answered "no". * In read-only mode all questions are answered "no".
@ -46,11 +47,13 @@ bool yes_or_no (bool read_only)
/* /*
* Get a line and see what the first character is. * Get a line and see what the first character is.
*/ */
c = fgetc(stdin);
/* TODO: use gettext */ /* TODO: use gettext */
if (fgets (buf, sizeof buf, stdin) == buf) { result = (c == 'y' || c == 'Y');
return buf[0] == 'y' || buf[0] == 'Y';
}
return false; while (c != '\n' && c != EOF)
c = fgetc(stdin);
return result;
} }