sam2p -- multiple issues

sam2p developers report:

In sam2p 0.49.3, a heap-based buffer overflow exists in the pcxLoadImage24 function of the file in_pcx.cpp.
In sam2p 0.49.3, the in_xpm_reader function in in_xpm.cpp has an integer signedness error, leading to a crash when writing to an out-of-bounds array element.
In sam2p 0.49.3, an integer overflow exists in the pcxLoadImage24 function of the file in_pcx.cpp, leading to an invalid write operation.
In sam2p 0.49.3, the pcxLoadRaster function in in_pcx.cpp has an integer signedness error leading to a heap-based buffer overflow.
Because of an integer overflow in sam2p 0.49.3, a loop executes 0xffffffff times, ending with an invalid read of size 1 in the Image::Indexed::sortPal function in image.cpp. However, this also causes memory corruption because of an attempted write to the invalid d[0xfffffffe] array element.
In sam2p 0.49.3, there is an invalid read of size 2 in the parse_rgb function in in_xpm.cpp. However, this can also cause a write to an illegal address.