mirror of
https://github.com/tailscale/tailscale.git
synced 2026-10-23 03:37:19 +09:00
Mike Jensenandchaosinthecrd
144f6b20f0
* k8s-operator,sessionrecording: fix SPDY protocol DoS risks There was a risk that a malicious kubectl client could cause a DoS issue for the Tailscale proxy performing a k8s recording by defining large quantities of headers, or using a decompression bomb. This change adds limits of 1000 header pairs, and a maximum of 1MB for the decompressed header block size. In addition fuzz testing is added and integrated with oss-fuzz to review for other protocol issues. Credit to Eresus Security for reporting the header quantity DoS risk. Fixes tailscale/corp#45112 Updates tailscale/corp#46608 Change-Id: Ie27b241b9f1cac58198560a88a44ffaa0927b96e Signed-off-by: Mike Jensen <mikej@tailscale.com> * k8s-operator/sessionrecording/spdy: test consecutive header blocks share one zlib context kubectl compresses every stream's header block against one zlib stream for the life of the connection, so the proxy decodes them all through a single zlibReader (conn.zlibReqReader). This test compresses two blocks onto one writer and decodes both from one reader. It fails on the second block: parseHeaders' ended() reads one byte past the first block, which on the shared context is the start of the next block, leaving the reader unable to decode it ("unexpected EOF"). In a real session that means every stream after the first fails to parse and its output is never recorded. Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk> * k8s-operator,sessionrecording: parse full 31-bit SPDY stream IDs dataFrameStreamID masked stream IDs to 7 bits while storeStreamID kept all 32, so output on any stream with ID >= 128 was never matched against a stored stdout/stderr stream and went unrecorded. Keep the 31 spec bits in both places. controlFrameVersion gets the matching 15-bit mask for its version field. Mask storeStreamID to 31 bits as well: the reserved flag bit in a SYN_STREAM ID field can never appear in a data frame, so an ID stored with the bit set matches nothing. Change-Id: Icf05a29a2838f2f2492b8d2da9e821f4e2459877 Signed-off-by: Mike Jensen <mikej@tailscale.com> --------- Signed-off-by: Mike Jensen <mikej@tailscale.com> Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk> Co-authored-by: chaosinthecrd <tom@tmlabs.co.uk>