fix: reject shell/exec request when Handler is nil instead of panic#258
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Yanhu007 wants to merge 1 commit intogliderlabs:masterfrom
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fix: reject shell/exec request when Handler is nil instead of panic#258Yanhu007 wants to merge 1 commit intogliderlabs:masterfrom
Yanhu007 wants to merge 1 commit intogliderlabs:masterfrom
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When a server only defines SubsystemHandlers (e.g. SFTP) without a session Handler, an SSH client sending a shell or exec request causes a nil pointer dereference panic at session.go:261. Add a nil check for sess.handler before accepting the request. When nil, the request is rejected with Reply(false, nil) instead of crashing. Fixes gliderlabs#237
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Fixes #237
Problem
When a server only defines
SubsystemHandlers(e.g. for SFTP) without setting a sessionHandler, an SSH client sending a shell or exec request causes a nil pointer dereference panic:Line 261:
sess.handler(sess)is called without checking ifhandleris nil.Fix
Add a nil check before accepting the request. When
handleris nil, reject the request withReply(false, nil)and continue processing, matching the existing pattern used for subsystem handler nil checks.Builds cleanly.