Add integer overflow checks to apreq parameter and cookie allocation#616
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kodareef5 wants to merge 2 commits intoapache:trunkfrom
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Add integer overflow checks to apreq parameter and cookie allocation#616kodareef5 wants to merge 2 commits intoapache:trunkfrom
kodareef5 wants to merge 2 commits intoapache:trunkfrom
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ap_escape_path_segment, ap_os_escape_path, and ap_escape_urlencoded allocate output buffers using 3 * strlen(input) + constant without checking for overflow. On platforms where size_t is 32-bit, large inputs cause the multiplication to wrap, resulting in undersized allocation. The HTML escape function ap_escape_html2 in the same file already has overflow protection (abort on overflow). Apply the same pattern to the three URL escape functions for consistency.
apreq_param_make(), apreq_param_decode(), apreq_param_encode(), and apreq_cookie_make() compute allocation sizes as nlen + vlen + constant without checking for overflow. On platforms where size_t is 32-bit, large parameter values can cause the sum to wrap, resulting in undersized allocation. Add overflow checks before each allocation, returning NULL or APR_ENOMEM on overflow. The URL-encode path (apreq_param_encode) also checks the 3 * (nlen + dlen) multiplication.
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apreq_param_make(),apreq_param_decode(),apreq_param_encode(), andapreq_cookie_make()compute allocation sizes asnlen + vlen + constantwithout checking for integer overflow. On platforms wheresize_tis 32-bit, large parameter or cookie values can cause the sum to wrap, resulting in undersized allocation.This adds overflow checks before each
apr_palloccall:apreq_param_make(server/apreq_param.c:38): checksnlen + vlen + 1 + sizeof *paramapreq_param_decode(server/apreq_param.c:84): same patternapreq_param_encode(server/apreq_param.c:144): checksnlen + dlenaddition and3 * summultiplicationapreq_cookie_make(server/apreq_cookie.c:143): checksnlen + vlen + 1 + sizeof *cOn overflow, each function returns
NULL(orAPR_ENOMEMforapreq_param_decode), consistent with existing allocation failure handling.