OS400: handle memory error in list conversion #3372
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Curl_slist_append_nodup() returns NULL when it fails to create a new item for the specified list, and since the coding here reassigned the new list on top of the old list it would result in a dangling pointer and lost memory. Also, in case we hit an allocation failure at some point during the conversion, with allocation succeeding again on the subsequent call(s) we will return a truncated list around the malloc failure point. Fix by assigning to a temporary list pointer, which can be checked (which is the common pattern for slist appending), and free all the resources on allocation failure.
bagder
approved these changes
Dec 13, 2018
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Curl_slist_append_nodup()returns NULL when it fails to create a new item for the specified list, and since the coding here reassigned the new list on top of the old list it would result in a dangling pointerand lost memory. Also, in case we hit an allocation failure at some point during the conversion, with allocation succeeding again on the subsequent call(s) we will return a truncated list around the malloc
failure point.
Fix by assigning to a temporary list pointer, which can be checked (which is the common pattern for slist appending), and free all the resources on allocation failure.
Disclaimer: I have not tested this since I have no access to an OS400 environment.