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Error out in rfbProcessFileTransferReadBuffer if length can not be allocated
re #273
1 parent a64c3b3 commit 15bb719

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Diff for: libvncserver/rfbserver.c

+12-2
Original file line numberDiff line numberDiff line change
@@ -1461,11 +1461,21 @@ char *rfbProcessFileTransferReadBuffer(rfbClientPtr cl, uint32_t length)
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int n=0;
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FILEXFER_ALLOWED_OR_CLOSE_AND_RETURN("", cl, NULL);
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/*
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rfbLog("rfbProcessFileTransferReadBuffer(%dlen)\n", length);
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We later alloc length+1, which might wrap around on 32-bit systems if length equals
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0XFFFFFFFF, i.e. SIZE_MAX for 32-bit systems. On 64-bit systems, a length of 0XFFFFFFFF
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will safely be allocated since this check will never trigger and malloc() can digest length+1
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without problems as length is a uint32_t.
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*/
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if(length == SIZE_MAX) {
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rfbErr("rfbProcessFileTransferReadBuffer: too big file transfer length requested: %u", (unsigned int)length);
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rfbCloseClient(cl);
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return NULL;
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}
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if (length>0) {
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buffer=malloc((uint64_t)length+1);
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buffer=malloc((size_t)length+1);
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if (buffer!=NULL) {
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if ((n = rfbReadExact(cl, (char *)buffer, length)) <= 0) {
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if (n != 0)

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