[SoftCSA] Add double-buffered keys to eliminate data race in descrambling#3702
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atvcaptain merged 2 commits intoopenatv:masterfrom Feb 10, 2026
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[SoftCSA] Add double-buffered keys to eliminate data race in descrambling#3702atvcaptain merged 2 commits intoopenatv:masterfrom
atvcaptain merged 2 commits intoopenatv:masterfrom
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…ling setKey() (CWHandler thread) and descramble() (recorder thread) access the same dvbcsa_bs_key_t concurrently. key_set_ecm() rewrites the internal key schedule while decrypt() reads it, causing intermittent audio dropouts and brief freezes. Each parity now has two key slots. setKey() writes the inactive slot, then atomically publishes the new index (release). descramble() snapshots the active index once per call (acquire) and uses it throughout, so it never sees a partially-written key schedule.
- Check return value of ::write() calls to wake pipe - Replace EWOULDBLOCK with EINTR (EAGAIN == EWOULDBLOCK on Linux, causing -Werror=logical-op failure)
atvcaptain
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Feb 10, 2026
…ling (#3702) * [SoftCSA] Add double-buffered keys to eliminate data race in descrambling setKey() (CWHandler thread) and descramble() (recorder thread) access the same dvbcsa_bs_key_t concurrently. key_set_ecm() rewrites the internal key schedule while decrypt() reads it, causing intermittent audio dropouts and brief freezes. Each parity now has two key slots. setKey() writes the inactive slot, then atomically publishes the new index (release). descramble() snapshots the active index once per call (acquire) and uses it throughout, so it never sees a partially-written key schedule. * [cwhandler] Fix build warnings treated as errors - Check return value of ::write() calls to wake pipe - Replace EWOULDBLOCK with EINTR (EAGAIN == EWOULDBLOCK on Linux, causing -Werror=logical-op failure)
jbleyel
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Feb 12, 2026
* master: Use windowTitle parameter instead of setTitle after init of MessageBox [CAHandler] Send CMD_NOT_SELECTED when last service is unregistered [SoftCSA] Suppress activation when CI module handles decryption Revert "[SoftCSA] Deactivate software descrambling when CI module handles decryption" pot update translation update [servicedvb] * re-enable precise recovery feature to fix time shift issues * add extra setting for hardware latency correction for DM9x0 [ChannelSelection] Fix new crash https://www.opena.tv/viewtopic.php?p=597368&sid=6f7566164c0518ad0230b534dfb5889e#p597368 translation update [SoftCSA] Add double-buffered keys to eliminate data race in descrambling (#3702) [cahandler] Skip CLIENT_INFO on reconnects for legacy softcams (#3700)
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setKey() (CWHandler thread) and descramble() (recorder thread) access
the same dvbcsa_bs_key_t concurrently. key_set_ecm() rewrites the
internal key schedule while decrypt() reads it, causing intermittent
audio dropouts and brief freezes.
Each parity now has two key slots. setKey() writes the inactive slot,
then atomically publishes the new index (release). descramble() snapshots
the active index once per call (acquire) and uses it throughout, so it
never sees a partially-written key schedule.