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 131E12D47CD; Mon, 5 May 2025 22:54:00 +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=1746485641; cv=none; b=gkJQ16uLKlNjOMRfFq91sOE2l+7SJEvwfDpWCQwDk7IeijRtexbkwb0ELN71FV187MsFo0qhz4yKf6kxkYadPopcTNkCxWKx3g/uWdCyBF/SV9wt36rQZHvnt/wxTIArBSviNBeHPIRhp46Rg4KN9Brco2aNvKqHGVtqNRfBnWc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746485641; c=relaxed/simple; bh=+wZxgz632sHvnLOgr6eoUPj4ket6MHQdjGTN8+zbFzE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=m5fWVpr9b/ME7ZwjpYgPAXsyYVC4yj6OlqO/Da8suzNL3caMdOLMJVRPqIGQqYTywfTIcdNCEt0CZtXQwO92/Tq+bXiISXUvoIjCkDPqzVXJJzCXaTmyst4KVBOJZoaSTiexxuJXArHCPqwdjcQtFN5lm6fNfY9VTcGk6FpwspA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fGtDIoeh; 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="fGtDIoeh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 496FAC4CEED; Mon, 5 May 2025 22:53:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746485639; bh=+wZxgz632sHvnLOgr6eoUPj4ket6MHQdjGTN8+zbFzE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fGtDIoehVn0264eGyISR/0K7vi68gTim5Dz8QBX00ajpppAhpgiDCyxpKs9VX3OnV XucYYZ6BQDjwekdF5W1rQn8DXRQPCE8RWTFb4/cCCNv66ikxqN9uygr3gQURrVk5Y6 /X9Y/B4tggTtkNv2VWB+TxJtsA035QmA/KHvMf7332e3E2sMm6CECKwCJwfI00GFKW f8UPhxVtw1fcJVWBEkl21606AdJqg8yee2+df5cO16cyA4oanHKpM1tPmHU8jgB0WR b0XqBMrqS6M+v1tGlr+SjlERShzGQqTNsR/mipTqGgh18nKHFu6tP7/cnXeGqS58iz KkZAFYsrCurHw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kees Cook , Sasha Levin , linux-hardening@vger.kernel.org Subject: [PATCH AUTOSEL 6.12 400/486] pstore: Change kmsg_bytes storage size to u32 Date: Mon, 5 May 2025 18:37:56 -0400 Message-Id: <20250505223922.2682012-400-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505223922.2682012-1-sashal@kernel.org> References: <20250505223922.2682012-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.26 Content-Transfer-Encoding: 8bit From: Kees Cook [ Upstream commit 5674609535bafa834ab014d90d9bbe8e89223a0b ] The types around kmsg_bytes were inconsistent. The global was unsigned long, the argument to pstore_set_kmsg_bytes() was int, and the filesystem option was u32. Given other internal limits, there's not much sense in making a single pstore record larger than INT_MAX and it can't be negative, so use u32 everywhere. Additionally, use READ/WRITE_ONCE and a local variable in pstore_dump() to avoid kmsg_bytes changing during a dump. Link: https://lore.kernel.org/r/20250206191655.work.798-kees@kernel.org Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- fs/pstore/inode.c | 2 +- fs/pstore/internal.h | 4 ++-- fs/pstore/platform.c | 11 ++++++----- 3 files changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c index 56815799ce798..9de6b280c4f41 100644 --- a/fs/pstore/inode.c +++ b/fs/pstore/inode.c @@ -265,7 +265,7 @@ static void parse_options(char *options) static int pstore_show_options(struct seq_file *m, struct dentry *root) { if (kmsg_bytes != CONFIG_PSTORE_DEFAULT_KMSG_BYTES) - seq_printf(m, ",kmsg_bytes=%lu", kmsg_bytes); + seq_printf(m, ",kmsg_bytes=%u", kmsg_bytes); return 0; } diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h index 801d6c0b170c3..a0fc511969100 100644 --- a/fs/pstore/internal.h +++ b/fs/pstore/internal.h @@ -6,7 +6,7 @@ #include #include -extern unsigned long kmsg_bytes; +extern unsigned int kmsg_bytes; #ifdef CONFIG_PSTORE_FTRACE extern void pstore_register_ftrace(void); @@ -35,7 +35,7 @@ static inline void pstore_unregister_pmsg(void) {} extern struct pstore_info *psinfo; -extern void pstore_set_kmsg_bytes(int); +extern void pstore_set_kmsg_bytes(unsigned int bytes); extern void pstore_get_records(int); extern void pstore_get_backend_records(struct pstore_info *psi, struct dentry *root, int quiet); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index f56b066ab80ce..557cf9d40177f 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -92,8 +92,8 @@ module_param(compress, charp, 0444); MODULE_PARM_DESC(compress, "compression to use"); /* How much of the kernel log to snapshot */ -unsigned long kmsg_bytes = CONFIG_PSTORE_DEFAULT_KMSG_BYTES; -module_param(kmsg_bytes, ulong, 0444); +unsigned int kmsg_bytes = CONFIG_PSTORE_DEFAULT_KMSG_BYTES; +module_param(kmsg_bytes, uint, 0444); MODULE_PARM_DESC(kmsg_bytes, "amount of kernel log to snapshot (in bytes)"); static void *compress_workspace; @@ -107,9 +107,9 @@ static void *compress_workspace; static char *big_oops_buf; static size_t max_compressed_size; -void pstore_set_kmsg_bytes(int bytes) +void pstore_set_kmsg_bytes(unsigned int bytes) { - kmsg_bytes = bytes; + WRITE_ONCE(kmsg_bytes, bytes); } /* Tag each group of saved records with a sequence number */ @@ -278,6 +278,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, struct kmsg_dump_detail *detail) { struct kmsg_dump_iter iter; + unsigned int remaining = READ_ONCE(kmsg_bytes); unsigned long total = 0; const char *why; unsigned int part = 1; @@ -300,7 +301,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, kmsg_dump_rewind(&iter); oopscount++; - while (total < kmsg_bytes) { + while (total < remaining) { char *dst; size_t dst_size; int header_size; -- 2.39.5