system/popen: close newfd correctly #3352
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Fixes a bug where newfd is not properly closed when newfd[0] equals newfd[1]. This can cause file descriptor leaks in certain edge cases where the read and write sides of the pipe are duplicated. Signed-off-by: hongfengchen <hongfengchen@xiaomi.com>
xiaoxiang781216
approved these changes
Jan 21, 2026
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Summary
This PR fixes a file descriptor leak in the
popen()implementation when the read and write file descriptors are duplicated (when newfd[0] equals newfd[1]).The bug was in the file descriptor cleanup logic where the condition
if (rw)alone was insufficient to handle the edge case where both pipe ends point to the same descriptor.Changes
system/popen/popen.cnewfd[0] != newfd[1]before closing the write-side file descriptorTesting
Tested with:
Verification Checklist