diff options
| author | Paul Buetow <paul@buetow.org> | 2026-05-30 21:59:43 +0300 |
|---|---|---|
| committer | Paul Buetow <paul@buetow.org> | 2026-05-30 21:59:43 +0300 |
| commit | fa7ab433b424d68e62612961d0128fbdaea3d64d (patch) | |
| tree | 9e97e959aa487aa8e04a8ea9d0309f759c04b230 /internal/generate/testdata.go | |
| parent | c1faab41f8576614f52089a972240de375237bd3 (diff) | |
test(dup): lock in fd_event handler captures oldfd (args[0])
Audit of dup(2) found the tracing implementation already correct and
consistent with its dup2/dup3 siblings: dup(int oldfd) takes a single fd
argument (the sys_enter_dup tracepoint exposes it as field "fildes",
unsigned int, at args[0]). It is classified KindFd (a plain fd_event),
the enter handler captures ev->fd from args[0] per the KindFd
convention, it is in the FS family (fd grouping), and its exit returns
the new (lowest-numbered unused) descriptor or -1 as a plain UNCLASSIFIED
ret_event (never a byte-count transfer). Like dup2, dup carries no flags
and clears FD_CLOEXEC on the duplicate; the eventloop registerDup path
registers the returned newfd onto the same underlying file with flags=0,
which it already honors (applyFdTransferOp handles SYS_ENTER_DUP).
Docs (FS, fd) and the drift tests are in sync; existing coverage already
includes TestClassifyDup, the makeFdDupTestData full-lifecycle eventloop
test, and integration TestDupBasic/TestDupInvalidFd.
No discrepancies were found, so add a lock-in test (matching the dup2
audit) asserting the generated BPF C for dup captures fd from args[0]
(not args[1]), emits an fd_event (not a dup3_event), wires no flags, and
classifies the exit UNCLASSIFIED. Adds FormatExitDup testdata to drive
the exit handler assertions.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Diffstat (limited to 'internal/generate/testdata.go')
| -rw-r--r-- | internal/generate/testdata.go | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/internal/generate/testdata.go b/internal/generate/testdata.go index 0d57029..6d6b6aa 100644 --- a/internal/generate/testdata.go +++ b/internal/generate/testdata.go @@ -540,6 +540,24 @@ format: print fmt: "fildes: 0x%08lx", ((unsigned long)(REC->fildes)) ` +// FormatExitDup mirrors the kernel's sys_exit_dup tracepoint. dup() returns the +// new (lowest-numbered unused) descriptor on success or -1 on error; that fd +// number is reported as a plain ret_event (UNCLASSIFIED), never a byte-count +// transfer, exactly like dup2/dup3. +const FormatExitDup = `name: sys_exit_dup +ID: 924 +format: + field:unsigned short common_type; offset:0; size:2; signed:0; + field:unsigned char common_flags; offset:2; size:1; signed:0; + field:unsigned char common_preempt_count; offset:3; size:1; signed:0; + field:int common_pid; offset:4; size:4; signed:1; + + field:int __syscall_nr; offset:8; size:4; signed:1; + field:long ret; offset:16; size:8; signed:1; + +print fmt: "0x%lx", REC->ret +` + const FormatDup2 = `name: sys_enter_dup2 ID: 920 format: |