GitHub user sl4mmy opened a pull request:
https://github.com/apache/zookeeper/pull/559
ZOOKEEPER-3079: avoid unsafe use of sprintf(3)
The function format_endpoint_info declares both addrstr and buf as 128
element char arrays, however on non-Windows platforms it calls
sprintf(3) to write into buf the value of addrstr followed by ':'
followed by the the port number. This causes a compiler error when
building with GCC 8 because this could potentially overflow buf if the
value of addrstr was ever 127 characters long (or a little less
depending on how many digits are in port). Of course, this couldn't
actually happen because addrstr is initialized by inet_ntop(3) which
won't write more than INET6_ADDRSTRLEN bytes (defined in <netinet/in.h>
on POSIX-compliant systems). Of course, GCC doesn't know that, so let's
just declare addrstr as a char array of only size INET6_ADDRSTRLEN
instead of 128.
Signed-off-by: Kent R. Spillner <kspill...@acm.org>
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/sl4mmy/zookeeper zookeeper-3079
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/zookeeper/pull/559.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #559
----
commit cb26e2f8d0704e1b5074c3e89c20962c5fc7f7b5
Author: Kent R. Spillner <kspillner@...>
Date: 2018-07-03T20:44:54Z
ZOOKEEPER-3079: avoid unsafe use of sprintf(3)
The function format_endpoint_info declares both addrstr and buf as 128
element char arrays, however on non-Windows platforms it calls
sprintf(3) to write into buf the value of addrstr followed by ':'
followed by the the port number. This causes a compiler error when
building with GCC 8 because this could potentially overflow buf if the
value of addrstr was ever 127 characters long (or a little less
depending on how many digits are in port). Of course, this couldn't
actually happen because addrstr is initialized by inet_ntop(3) which
won't write more than INET6_ADDRSTRLEN bytes (defined in <netinet/in.h>
on POSIX-compliant systems). Of course, GCC doesn't know that, so let's
just declare addrstr as a char array of only size INET6_ADDRSTRLEN
instead of 128.
Signed-off-by: Kent R. Spillner <kspill...@acm.org>
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