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 87C4E2FE584 for ; Tue, 12 Aug 2025 18:47:45 +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=1755024465; cv=none; b=Mg/htacwvrt+DokXDxFLhZV6ifxl7Oegbizw5DM+GA1WGOGoDdFb+ZArlAw1UycEiyXVOdxZjJBaXG9I0Cn2qTvefqYVRDo+o2ZkOEVsE601Q3GRF7ATyho7dfv0FpGtV40VQmoKRyQrQp1FQd+/sFiHfq9kPna50XSR7FmA5ZE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755024465; c=relaxed/simple; bh=CziuQVh4iq7lLlvhoxXKN6Q55B4af9Mr5xTJrXqsevw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XqYBnujZGNaLLOAt6I/kTThe+R4vwOt3xxThChGJ1BoeYFTsxs4R44hbWkYQVE35uSbuQuT3ycgAv66d1cE5UpagARDvXeg4xZybP7dW8fYqbHEsC1k0k+8WE4PbsTLN0hemIhXXimUcKltrdPgoEUR1AbBr9F+OwLO/5h8R+ZI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mU2Jz2sT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mU2Jz2sT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20F9EC4CEF0; Tue, 12 Aug 2025 18:47:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755024465; bh=CziuQVh4iq7lLlvhoxXKN6Q55B4af9Mr5xTJrXqsevw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mU2Jz2sT0KfDULUgAILmkgcQUcyEJxPzGzof4NEhgKSSji0+vbOxgq+O0kmZJunxQ 5wZbxYYKbETSCgBn9LlkS3QOlc8J2/9tCvymxMKnlPVGhuoCnXS9uLfC443FAlkJzF UtccAjcMl8mpJz88NnmJp7Y6ncoWj8bWOIFkJW4tG/T357Bcgr2CWS9tNmbgY35Joz CaPqIFoN1Pa8R6LjMEMoAlTE8ndS2KuvUF7tadz26IlVrXe27v/pF0PLxkqMCnCs/w hhBpWKNUDjo2qaz7uWzKY9NR8FpUFmKgefRZx3lULVSLzTfg0LmxWlNmdxXfZGGUoN z+Nx6a6zKk0fQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Thorsten Blum , Namjae Jeon , Steve French , Sasha Levin Subject: [PATCH 6.16.y] smb: server: Fix extension string in ksmbd_extract_shortname() Date: Tue, 12 Aug 2025 14:47:40 -0400 Message-Id: <20250812184740.2027825-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <2025081238-unnamed-nappy-9be5@gregkh> References: <2025081238-unnamed-nappy-9be5@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Thorsten Blum [ Upstream commit 8e7d178d06e8937454b6d2f2811fa6a15656a214 ] In ksmbd_extract_shortname(), strscpy() is incorrectly called with the length of the source string (excluding the NUL terminator) rather than the size of the destination buffer. This results in "__" being copied to 'extension' rather than "___" (two underscores instead of three). Use the destination buffer size instead to ensure that the string "___" (three underscores) is copied correctly. Cc: stable@vger.kernel.org Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Signed-off-by: Thorsten Blum Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/smb/server/smb_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/smb/server/smb_common.c b/fs/smb/server/smb_common.c index 425c756bcfb8..b23203a1c286 100644 --- a/fs/smb/server/smb_common.c +++ b/fs/smb/server/smb_common.c @@ -515,7 +515,7 @@ int ksmbd_extract_shortname(struct ksmbd_conn *conn, const char *longname, p = strrchr(longname, '.'); if (p == longname) { /*name starts with a dot*/ - strscpy(extension, "___", strlen("___")); + strscpy(extension, "___", sizeof(extension)); } else { if (p) { p++; -- 2.39.5