From 69e75c8581e15328454bb6e2f1dc347f73616b37 Mon Sep 17 00:00:00 2001 From: Alan Donovan Date: Tue, 23 Apr 2024 12:44:54 -0400 Subject: runtime: properly frame panic values in tracebacks This CL causes the printing of panic values to ensure that all newlines in the output are immediately followed by a tab, so that there is no way for a maliciously crafted panic value to fool a program attempting to parse the traceback into thinking that the panic value is in fact a goroutine stack. See https://github.com/golang/go/issues/64590#issuecomment-1932675696 + release note Updates #64590 Updates #63455 Change-Id: I5142acb777383c0c122779d984e73879567dc627 Reviewed-on: https://go-review.googlesource.com/c/go/+/581215 Auto-Submit: Alan Donovan LUCI-TryBot-Result: Go LUCI Reviewed-by: Michael Pratt --- src/runtime/panic.go | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'src/runtime/panic.go') diff --git a/src/runtime/panic.go b/src/runtime/panic.go index 51b57520c1..27fcf73ff4 100644 --- a/src/runtime/panic.go +++ b/src/runtime/panic.go @@ -656,7 +656,7 @@ func printpanics(p *_panic) { return } print("panic: ") - printany(p.arg) + printpanicval(p.arg) if p.recovered { print(" [recovered]") } @@ -718,20 +718,20 @@ func gopanic(e any) { gp := getg() if gp.m.curg != gp { print("panic: ") - printany(e) + printpanicval(e) print("\n") throw("panic on system stack") } if gp.m.mallocing != 0 { print("panic: ") - printany(e) + printpanicval(e) print("\n") throw("panic during malloc") } if gp.m.preemptoff != "" { print("panic: ") - printany(e) + printpanicval(e) print("\n") print("preempt off reason: ") print(gp.m.preemptoff) @@ -740,7 +740,7 @@ func gopanic(e any) { } if gp.m.locks != 0 { print("panic: ") - printany(e) + printpanicval(e) print("\n") throw("panic holding locks") } @@ -1015,7 +1015,9 @@ func throw(s string) { // Everything throw does should be recursively nosplit so it // can be called even when it's unsafe to grow the stack. systemstack(func() { - print("fatal error: ", s, "\n") + print("fatal error: ") + printpanicval(s) + print("\n") }) fatalthrow(throwTypeRuntime) @@ -1034,7 +1036,9 @@ func fatal(s string) { // Everything fatal does should be recursively nosplit so it // can be called even when it's unsafe to grow the stack. systemstack(func() { - print("fatal error: ", s, "\n") + print("fatal error: ") + printpanicval(s) + print("\n") }) fatalthrow(throwTypeUser) -- cgit v1.3