From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1798535AABE for ; Thu, 11 Sep 2025 16:54:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757609644; cv=none; b=MrYkuB0AsixVjbI4APggL0vvfkIArJFUjL1QplvvCbdsuMfSswI170OFjHNmBIg27gJ7XxyJtX1h0Bzh7aZUUTrLVcd+1BDRi40fwja2CfA5CrEJhhAejjRJl5s0qT3V8SCTyttWrwLcfzBhNiR1Cb4X0QDGRJujgBd10Qj3BjM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757609644; c=relaxed/simple; bh=8FaX4inOOsmBa/0SidpGxx0RuDP0UWToatFrcOorG84=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=W9QScmgZAN6ICz2M6wmQSvD5FpoMo6fYA0yxXp4Z4KemnpshGprZWl7ZW5yt6uMvYDUD2gZt6y6wjdAVuJKh7woot4WBIlvHZDBay77Af4UmtbJhCbZu48CKd+oe05CxSWZdSBj6D37z9z6fV01oBVyTCV9OMUcV8AjldupV0oo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FeM9XyMH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FeM9XyMH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 920A6C4CEF0; Thu, 11 Sep 2025 16:54:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1757609644; bh=8FaX4inOOsmBa/0SidpGxx0RuDP0UWToatFrcOorG84=; h=From:To:Cc:Subject:Date:Reply-to:From; b=FeM9XyMHY+1tLXVZwXFj18IOaB+1/bXDE0xnGDTtlB9DIwQY5RwOAog+vpiD7+ddP yFskizdVX9f+kSmHyJHgbe9QdZSSzZfbS/4zo7HvgxpFvPyHXEEz5bH6u+TUNTcDuz PcpH0PmLd3DrGxtEpnVM/tCPfTuULylAJefunTUk= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2025-39758: RDMA/siw: Fix the sendmsg byte count in siw_tcp_sendpages Date: Thu, 11 Sep 2025 18:52:58 +0200 Message-ID: <2025091144-CVE-2025-39758-eaf0@gregkh> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reply-to: , X-Developer-Signature: v=1; a=openpgp-sha256; l=4474; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=jhSNUBsLHycXcz5V4xdr0V2qVKSPiiuCE5pW7q3y7hA=; b=owGbwMvMwCRo6H6F97bub03G02pJDBmH/sWWVzTJK5/bUNrwMmn5o61e/dPEcu7ffWtnNGths /9LFVbmjlgWBkEmBlkxRZYv23iO7q84pOhlaHsaZg4rE8gQBi5OAZjIBzWG+RH5LVpC+Yd19Gee mb5y44c54X7SeQzzI3/39jXp7lZh6iuW//jxw/dLSkt4AA== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Fix the sendmsg byte count in siw_tcp_sendpages Ever since commit c2ff29e99a76 ("siw: Inline do_tcp_sendpages()"), we have been doing this: static int siw_tcp_sendpages(struct socket *s, struct page **page, int offset, size_t size) [...] /* Calculate the number of bytes we need to push, for this page * specifically */ size_t bytes = min_t(size_t, PAGE_SIZE - offset, size); /* If we can't splice it, then copy it in, as normal */ if (!sendpage_ok(page[i])) msg.msg_flags &= ~MSG_SPLICE_PAGES; /* Set the bvec pointing to the page, with len $bytes */ bvec_set_page(&bvec, page[i], bytes, offset); /* Set the iter to $size, aka the size of the whole sendpages (!!!) */ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size); try_page_again: lock_sock(sk); /* Sendmsg with $size size (!!!) */ rv = tcp_sendmsg_locked(sk, &msg, size); This means we've been sending oversized iov_iters and tcp_sendmsg calls for a while. This has a been a benign bug because sendpage_ok() always returned true. With the recent slab allocator changes being slowly introduced into next (that disallow sendpage on large kmalloc allocations), we have recently hit out-of-bounds crashes, due to slight differences in iov_iter behavior between the MSG_SPLICE_PAGES and "regular" copy paths: (MSG_SPLICE_PAGES) skb_splice_from_iter iov_iter_extract_pages iov_iter_extract_bvec_pages uses i->nr_segs to correctly stop in its tracks before OoB'ing everywhere skb_splice_from_iter gets a "short" read (!MSG_SPLICE_PAGES) skb_copy_to_page_nocache copy=iov_iter_count [...] copy_from_iter /* this doesn't help */ if (unlikely(iter->count < len)) len = iter->count; iterate_bvec ... and we run off the bvecs Fix this by properly setting the iov_iter's byte count, plus sending the correct byte count to tcp_sendmsg_locked. The Linux kernel CVE team has assigned CVE-2025-39758 to this issue. Affected and fixed versions =========================== Issue introduced in 6.5 with commit c2ff29e99a764769eb2ce3a1a5585013633ee9a6 and fixed in 6.6.103 with commit 5661fdd218c2799001b88c17acd19f4395e4488e Issue introduced in 6.5 with commit c2ff29e99a764769eb2ce3a1a5585013633ee9a6 and fixed in 6.12.43 with commit 673cf582fd788af12cdacfb62a6a593083542481 Issue introduced in 6.5 with commit c2ff29e99a764769eb2ce3a1a5585013633ee9a6 and fixed in 6.15.11 with commit 42ebc16d9d2563f1a1ce0f05b643ee68d54fabf8 Issue introduced in 6.5 with commit c2ff29e99a764769eb2ce3a1a5585013633ee9a6 and fixed in 6.16.2 with commit edf82bc8150570167a33a7d54627d66614cbf841 Issue introduced in 6.5 with commit c2ff29e99a764769eb2ce3a1a5585013633ee9a6 and fixed in 6.17-rc1 with commit c18646248fed07683d4cee8a8af933fc4fe83c0d Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2025-39758 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: drivers/infiniband/sw/siw/siw_qp_tx.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/5661fdd218c2799001b88c17acd19f4395e4488e https://git.kernel.org/stable/c/673cf582fd788af12cdacfb62a6a593083542481 https://git.kernel.org/stable/c/42ebc16d9d2563f1a1ce0f05b643ee68d54fabf8 https://git.kernel.org/stable/c/edf82bc8150570167a33a7d54627d66614cbf841 https://git.kernel.org/stable/c/c18646248fed07683d4cee8a8af933fc4fe83c0d