re: fs/ntfs3: Add option "nocase"

[Colin King (gmail)]

Hi,

Static analysis with clang scan build has detected an issue in the 
following commit:

commit a3a956c78efaa202b1d75190136671cf6e87bfbe
Author: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
Date:   Fri Sep 23 12:42:18 2022 +0300

    fs/ntfs3: Add option "nocase"


The issue is as follows in fs/ntfs3/index.c in function ntfs_d_compare:

        /* First try fast implementation. */
        for (;;) {
                if (!lm--) {
                        ret = len1 == len2 ? 0 : 1;
                        goto out;
                }

                if ((c1 = *n1++) == (c2 = *n2++))
                        continue;

                if (c1 >= 0x80 || c2 >= 0x80)
                        break;

                if (toupper(c1) != toupper(c2)) {
                        ret = 1;
                        goto out;
                }
        }

...
...

out:
        __putname(uni1);
        return ret;
}

The exits in the for-loop via label out are ending up with __putname() 
being called on an uninitialized uni1 pointer.

Colin