Fix GH-16232: bitshift overflow on wbmp file content reading. #16239
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nielsdos
requested changes
Oct 5, 2024
ext/gd/libgd/wbmp.c
Outdated
| @@ -44,6 +44,9 @@ getmbi (int (*getin) (void *in), void *in) | |||
| i = getin (in); | |||
| if (i < 0) | |||
| return (-1); | |||
| long long chk = (long long)(mbi) << 7; | |||
| if (chk > INT_MAX || (chk | (long long)(i & 0x7f)) > INT_MAX) | |||
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How can the second condition ever be true? i & 0x7f is at most 0x7f, ORing t hat with chk will not allow you to reach the limit.
Note that this bug was already fixed upstream by libgd/libgd@a8f1d5c
nielsdos
approved these changes
Oct 5, 2024
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