From nobody Fri Feb 27 15:41:15 2026 X-Original-To: bugs@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4fMsxR4k0Vz6TJxB for ; Fri, 27 Feb 2026 15:41:15 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R12" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4fMsxR3zG5z3mGP for ; Fri, 27 Feb 2026 15:41:15 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1772206875; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=sNLSKr1KsXoXPSsmKesnatSaw922/NLKy1ibgInXMeI=; b=UwuCfqUyTZ0NIvfAJdjO8sj7SwNWqxcKx4S+LS8xdlRqr0rFK9Wk1ceftRQjNzJIWOKvx6 LHXDLaJLarlKIQEZSw1/jKSnlAAPktXzB+Tv9rymDDcNVpo0cr+NyjBA692QR75ZYpQtBR +NQzw1F5kKW+7WkgLFHrNtXUTSQEr3N6fyWSInbXK68el50b+4oiLaO6dCI+30WdXLFQ0O LPg/tUmM8yeFErxWL4HhQ5LtN4098AejCAZz8E6Den7fSzl+MC9mG0k11ay1WXWt6ul08v R0frBHVxP3sS3Zu5gJ3EinzsqT5oYFfo9KRuYj8oJx3v5j0o+p0XcesWQxkvDg== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1772206875; a=rsa-sha256; cv=none; b=QejySEgotDAwY8+NXMTWzo9T/gsojLIzkifBnUs+BZHWh57T+xZCXp5glRziu+3pGgE5kt qDL5HfHT599ohP4OffFMc1UUiTwrU7xfo5p5wkS5DLhh/Y2Gr5csLtVx4byvrBP6E+XTPD HFZjwYDjiTv6udcGWKQn3UZhcd17J4DB+QFmrUId4pi7ayKB+6KVzzL+oP2Hur/BX952CP 9lJRFsg3cf0Wns5Ikdo8v0UxPXDqDRenjjBsXASNIGbWYVTB3bcbUWK/6+kQAxjvbuxqW5 jOxNKodln4HAFuGOJynFIRX/QVe7dlJ3DR39FHEQPkT0/nnIECbTxQOZpzITCQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1772206875; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=sNLSKr1KsXoXPSsmKesnatSaw922/NLKy1ibgInXMeI=; b=NC1HFy5s3Tr8Vp5w/L+YxmaIARBdh9P0Ja83FosUoYBpgiY/k7e4ZiUs0EyDHuWefoieT3 KxQyk3JQuQtd/hCPM1DGC+Wy7ftW6UldN9O+SoK3alfxxqdlch5F9bDuU7tE1mm/wpbNUF B/gw8myhu8RsIiY42Js9DZEbfJwcFj1Qh9p9T7aqwVgRjZPr7oGfoGxnvZXXL4xk2lFW3P ae4pyjlRwyy8PyzDqU8vRXPdSuMGEDh1OIeiGkj3Lm3sG2MspbYUhcbNMIMEgNmS/vEY0b 4/whKG14vV86GJx3ie+sWceq93BNnBsiLsnWSNhDsIqA1zCLXj0gejaSs5LV7Q== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4fMsxR3XHkz7k8 for ; Fri, 27 Feb 2026 15:41:15 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 61RFfF4e085491 for ; Fri, 27 Feb 2026 15:41:15 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 61RFfFaO085490 for bugs@FreeBSD.org; Fri, 27 Feb 2026 15:41:15 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 293489] readv(2) on cuse device never returns Date: Fri, 27 Feb 2026 15:41:15 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: 15.0-RELEASE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: unitrunker@unitrunker.net X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Bug reports List-Archive: https://lists.freebsd.org/archives/freebsd-bugs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-bugs@FreeBSD.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D293489 Bug ID: 293489 Summary: readv(2) on cuse device never returns Product: Base System Version: 15.0-RELEASE Hardware: amd64 OS: Any Status: New Severity: Affects Only Me Priority: --- Component: bin Assignee: bugs@FreeBSD.org Reporter: unitrunker@unitrunker.net Issuing a read(2) on a cuse device that has data to returns works as expect= ed. When switching to readv(2) with eight iovec-s, the readv call never returns. Logging from an instrumented cuse device shows the first read is passed the correct buffer address and size. The data appears to be transferred. All subsequent read requires processed inside the cuse device have a correct bu= ffer address but the length is zero. Code snippet follows: #include #include int okay; char chunk[8]; struct iovec list[8] =3D { {chunk + 0, 1}, {chunk + 1, 1}, {chunk + 2, 1}, {chunk + 3, 1}, {chunk + 4, 1}, {chunk + 5, 1}, {chunk + 6, 1}, {chunk + 7, 1} }; int handle =3D open(/dev/cuse123", O_RDONLY); do { okay =3D readv(handle, list, 8); if (okay < 0) break; write(2, chunk, okay); } while (true); close(handle); Switching back to a simple read(2) call works as expected. The underlying issue is likely inside the cuse kernel module but this is ju= st a guess. --=20 You are receiving this mail because: You are the assignee for the bug.=