Fix race condition in CFPreferences #4903
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In __CFWriteBytesToFileWithAtomicity(), we first write the contents of the plist to an auxiliary copy file, and then move that copy to where the original used to be. Because that file needs to have the same owner as the original, we would use chown() to change ownership as the last step. This allows a race condition where the new file is in its final location, but doesn't have the correct permissions. To fix this, call chown() on the file before moving. rdar://121597642
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@swift-ci please test |
parkera
approved these changes
Mar 12, 2024
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In __CFWriteBytesToFileWithAtomicity(), we first write the contents of the plist to an auxiliary copy file, and then move that copy to where the original used to be. Because that file needs to have the same owner as the original, we would use chown() to change ownership as the last step. This allows a race condition where the new file is in its final location, but doesn't have the correct permissions. To fix this, call chown() on the file before moving.
rdar://121597642