From patchwork Fri Jan 10 12:57:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugen Hristev X-Patchwork-Id: 13934536 Received: from mail-wm1-f42.google.com (mail-wm1-f42.google.com [209.85.128.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 18A5520DD56 for ; Fri, 10 Jan 2025 12:57:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.42 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736513846; cv=none; b=qw4CFEtk6EorQ4ffru/4eKD8JzGDz/5p31Mt8WrT6MdcosdjeyvRMgi40YRImcwaby4LsUeKMa4nX2cG2LnKbmlx5QSQkxBpS7TdyFNpWt3JUPeUvTNNiNJAfczSkpeLdBy6gfOA8Fk/arXmR03UIfEktUxhpFkX4PT5Y7S5/ZE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736513846; c=relaxed/simple; bh=O7s4+YeAaeOezbUQ0uUAF3HuaRoXn0zbYMHRN4K94VA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ccelgRyJL6J++ylYMYK5Lvk53VRE/zCBG0FVvDJUj8PJZf1Fvt6zibVpPX+e5l67JGcFYcCW7mQ4P/ZYT6HhVsgXuZP2kp2E3i75A0Y/1C9RelERZHBytQfD49VzS5OD+VfecKHtc5GvKvDFCrOhHyJ1DBFD0hlithdz+ot5bPM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=UkKQlMQB; arc=none smtp.client-ip=209.85.128.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="UkKQlMQB" Received: by mail-wm1-f42.google.com with SMTP id 5b1f17b1804b1-43625c4a50dso15513015e9.0 for ; Fri, 10 Jan 2025 04:57:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1736513841; x=1737118641; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=JuO/PfXVbd8eOsHL6xLYlrc5CHMwEpP9FRyOGs7V7z0=; b=UkKQlMQBprwPiUHiXM8r9Q16K05oJlM4GRY1hZjF/gbZfhkubsyXL7rZFL1DbhYmo3 2C/9n0D2KTzqkUMmjDLpmZAoux12gZUWsDY0v00PPSKC56eaAhW5BDNJl2othY/1odoo qQG6d/t6bqQ2FifpJlo2tE1rRGoZn8QxmoaqmuYWyCJexP/nI1sovhaXT6J2xTZEIh4c PYwgyNZ0wGk7kJQeU1/BofJPgUQ+p9d+QRF9mRzLEmXzE9oVbqxzsN51Pubm4IBPbTRm mkVELCeFAzx2uo4xxBlFLIJ0XEOkJWaRXV42EnN4PveFx6MkcJbse4rB95Wk/T5Ud7z5 QgSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736513841; x=1737118641; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=JuO/PfXVbd8eOsHL6xLYlrc5CHMwEpP9FRyOGs7V7z0=; b=ZBvBoJDQ6LW63LgwGxSs/POSRocvVe5svlVHRaxtqnmBiXowucO1XYdf8DMGVbxELy W6NHNXF+eALpO9QteCW8xcVhEkBN1C93RDmlyngIDzwYvBjyfxRMylpNNOS3eh15l7Gm o1pkd7xMyajODgwYVZUS/u7f9WUHTpmw61n/ulWJLXaW34c9B37KLNvCQ8E8Gt5ESYzU WSiyAKprh9dT+Qr4l98o/vVt0Wr7OhQBs3XE/5cnZKmc6FQfLIGBQzh2wE7j5yXim9rV mUY3CQSngfWUpw1dof1CRF/5mQbQkOgvD/6NHs4qutFZTakGlXVJB4D9q9xkH1d6QKra 9VbA== X-Forwarded-Encrypted: i=1; AJvYcCW/pvm2T8jDvnW+/zhXthoDifH1a03RUKDzJLTCQTgWfoZcEgHh7+7AfbqTsaLQbYT/GdB+K6qWM2L3/Iju8ro=@vger.kernel.org X-Gm-Message-State: AOJu0Yz1cOnecA3dvpS2IYDEBSI9/irt27yWlcCyeKGT4csN+l6+QF6g 8Pz0JK2jGFBeOPfgAGrgtosp/MawiEHUDhsJWIrFP26p3xf0L8aoRgj5o0Drnqi9A5aC2U0WXAA rwgagwQ== X-Gm-Gg: ASbGncuCLbx+NUHs1VkDT+ihTyUpsqEvKzKvqEm66ieVS93emHiESXYgpBWzgS5viId HN89Fd5jZOoDQ7m8wbzhQm7X+o0tV1Xn+DpLv6SSI5mpUYcBsUjzX8ZE6TTtO1xN8ZJd5oUYNud CNqjkCxl04RvmaBXlpT/PNurSb/UNQZlR3Dv5YUCurzc6f0fuhis3PrYjDbXY/pm8EqOl5BZ62V 43D9m5afQXUVc+Lzvx5UNYZvZROIRBRJ3zyHH9lrm9OgmO9A2SHErrdvJGTcapWnoA= X-Google-Smtp-Source: AGHT+IF1ZIPyhPMIsBOrLkPqMM0CspLLHLyCMAkP93UYVxdRI64cHbeoj+KnpGweyYlZfjm5rQo/Ww== X-Received: by 2002:a05:600c:a09:b0:434:f1e9:afb3 with SMTP id 5b1f17b1804b1-436e267863emr91888235e9.3.1736513841515; Fri, 10 Jan 2025 04:57:21 -0800 (PST) Received: from eugen-station.. ([91.75.105.130]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-436e2ddcb5bsm87602755e9.23.2025.01.10.04.57.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Jan 2025 04:57:20 -0800 (PST) From: Eugen Hristev To: liaoweixiong@allwinnertech.com, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org Cc: kees@kernel.org, gpiccoli@igalia.com, tony.luck@intel.com, Eugen Hristev Subject: [PATCH v2] pstore/zone: avoid dereferencing zero sized ptr after init zones Date: Fri, 10 Jan 2025 14:57:14 +0200 Message-ID: <20250110125714.2594719-1-eugen.hristev@linaro.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In psz_init_zones, if the requested area has a total_size less than record_size, kcalloc will be called with c == 0 and will return ZERO_SIZE_PTR. Further, this will lead to an oops. With this patch, in this scenario, it will look like this : [ 6.865545] pstore_zone: total size : 28672 Bytes [ 6.865547] pstore_zone: kmsg size : 65536 Bytes [ 6.865549] pstore_zone: pmsg size : 0 Bytes [ 6.865551] pstore_zone: console size : 0 Bytes [ 6.865553] pstore_zone: ftrace size : 0 Bytes [ 6.872095] pstore_zone: zone dmesg total_size too small [ 6.878234] pstore_zone: alloc zones failed Signed-off-by: Eugen Hristev --- Changes in v2: - reworked to check for c==0 instead of ZERO_SIZE_PTR as suggested by Kees Cook fs/pstore/zone.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c index 694db616663f..ceb5639a0629 100644 --- a/fs/pstore/zone.c +++ b/fs/pstore/zone.c @@ -1212,6 +1212,11 @@ static struct pstore_zone **psz_init_zones(enum pstore_type_id type, } c = total_size / record_size; + if (unlikely(!c)) { + pr_err("zone %s total_size too small\n", name); + return ERR_PTR(-EINVAL); + } + zones = kcalloc(c, sizeof(*zones), GFP_KERNEL); if (!zones) { pr_err("allocate for zones %s failed\n", name);