From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
To: Jason Baron <jbaron@akamai.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org,
Rasmus Villemoes <linux@rasmusvillemoes.dk>
Subject: [PATCH v2 23/23] x86: dynamic_debug: protect against dynamic debug identifier reuse
Date: Tue, 9 Oct 2018 13:20:13 +0200 [thread overview]
Message-ID: <20181009112013.14238-24-linux@rasmusvillemoes.dk> (raw)
In-Reply-To: <20181009112013.14238-1-linux@rasmusvillemoes.dk>
Most invocations of DEFINE_DYNAMIC_DEBUG_METADATA happen through
"public" macros such as pr_debug or netdev_dbg, which have been updated
to ensure they pass a unique identifier to use as the name for the
struct _ddebug instance. But it is still possible that someone invokes
DEFINE_DYNAMIC_DEBUG_METADATA directly, or creates a new wrapper macro
that does not do the extra-level-of-macros-passing-on-a__UNIQUE_ID
dance. On x86-64, all subsequent uses of that same identifier would
silently reuse the first instance, which is bad.
But we can catch such cases by defining a guard symbol that is unique
per expansion of DEFINE_DYNAMIC_DEBUG_METADATA. This still allows gcc to
emit multiple copies of some static inline function that has a pr_debug
call (because all such copies would pass the same value of %5 to the
assembler), but prevents repeated naked
DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, "bla") - even with a helpful
error message saying that '"descriptor" used as _ddebug identifer more
than once'.
Acked-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
---
arch/x86/include/asm/dynamic_debug.h | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/dynamic_debug.h b/arch/x86/include/asm/dynamic_debug.h
index 350ef6e2feff..69167f40482c 100644
--- a/arch/x86/include/asm/dynamic_debug.h
+++ b/arch/x86/include/asm/dynamic_debug.h
@@ -26,10 +26,15 @@
"\t.long 0 \t# <padding>\n" \
_DPRINTK_ASM_KEY_INIT \
".popsection\n" \
+ ".set "__stringify(name)".ddebug.once, %c5\n" \
+ ".elseif "__stringify(name)".ddebug.once - %c5\n" \
+ ".line "__stringify(__LINE__) " - 1\n" \
+ ".error \"'"__stringify(name)"' used as _ddebug identifier more than once\"\n" \
".endif\n" \
: : "i" (KBUILD_MODNAME), "i" (__func__), \
"i" (__FILE__), "i" (fmt), \
- "i" (_DPRINTK_FLAGS_LINENO_INIT))
+ "i" (_DPRINTK_FLAGS_LINENO_INIT), \
+ "i" (__COUNTER__))
#endif /* _ASM_X86_DYNAMIC_DEBUG_H */
--
2.19.1.3.g1d92a00e68
next prev parent reply other threads:[~2018-10-09 11:20 UTC|newest]
Thread overview: 107+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-19 22:04 [PATCH 00/22] various dynamic_debug patches Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 01/22] linux/device.h: use DYNAMIC_DEBUG_BRANCH in dev_dbg_ratelimited Rasmus Villemoes
2018-09-20 8:47 ` Greg Kroah-Hartman
2018-09-19 22:04 ` [PATCH 02/22] linux/device.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-09-20 8:47 ` Greg Kroah-Hartman
2018-09-19 22:04 ` [PATCH 03/22] linux/net.h: use DYNAMIC_DEBUG_BRANCH in net_dbg_ratelimited Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 04/22] linux/net.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 05/22] linux/printk.h: use DYNAMIC_DEBUG_BRANCH in pr_debug_ratelimited Rasmus Villemoes
2018-09-27 7:52 ` Petr Mladek
2018-09-19 22:04 ` [PATCH 06/22] linux/printk.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-09-27 8:22 ` Petr Mladek
2018-09-27 8:41 ` Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 07/22] dynamic_debug: consolidate DEFINE_DYNAMIC_DEBUG_METADATA definitions Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 08/22] dynamic_debug: don't duplicate modname in ddebug_add_module Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 09/22] dynamic_debug: use pointer comparison in ddebug_remove_module Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 10/22] dynamic_debug: remove unused EXPORT_SYMBOLs Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 11/22] dynamic_debug: move pr_err from module.c to ddebug_add_module Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 12/22] dynamic_debug: add static inline stub for ddebug_add_module Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 13/22] dynamic_debug: refactor dynamic_pr_debug and friends Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 14/22] btrfs: implement btrfs_debug* in terms of helper macro Rasmus Villemoes
2018-09-20 13:10 ` David Sterba
2018-09-20 14:11 ` Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 15/22] ACPI: use proper DYNAMIC_DEBUG_BRANCH macro Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 16/22] ACPI: remove unused __acpi_handle_debug macro Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 17/22] ACPI: implement acpi_handle_debug in terms of _dynamic_func_call Rasmus Villemoes
2018-09-20 8:05 ` Rafael J. Wysocki
2018-09-19 22:04 ` [PATCH 18/22] dynamic_debug: introduce accessors for string members of struct _ddebug Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 19/22] dynamic_debug: drop use of bitfields in " Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 20/22] dynamic_debug: introduce CONFIG_DYNAMIC_DEBUG_RELATIVE_POINTERS Rasmus Villemoes
2018-09-19 22:04 ` [PATCH 21/22] x86: jump_label: introduce ASM_STATIC_KEY_INIT_{TRUE,FALSE} Rasmus Villemoes
2018-10-02 8:21 ` Rasmus Villemoes
2018-10-02 9:48 ` Ingo Molnar
2018-09-19 22:04 ` [PATCH 22/22] x86_64: use relative pointers with dynamic debug Rasmus Villemoes
2018-09-20 10:56 ` [PATCH 23/22] x86: dynamic_debug: protect against dynamic debug identifier reuse Rasmus Villemoes
2018-10-02 9:50 ` [PATCH 22/22] x86_64: use relative pointers with dynamic debug Ingo Molnar
2018-10-03 21:40 ` Rasmus Villemoes
2018-09-20 8:05 ` [PATCH 00/22] various dynamic_debug patches Rafael J. Wysocki
2018-10-03 9:25 ` Rafael J. Wysocki
2018-09-22 0:27 ` Jason Baron
2018-10-09 11:19 ` [PATCH v2 00/23] " Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 01/23] linux/device.h: use DYNAMIC_DEBUG_BRANCH in dev_dbg_ratelimited Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 02/23] linux/device.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 03/23] linux/net.h: use DYNAMIC_DEBUG_BRANCH in net_dbg_ratelimited Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 04/23] linux/net.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 05/23] linux/printk.h: use DYNAMIC_DEBUG_BRANCH in pr_debug_ratelimited Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 06/23] linux/printk.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 07/23] dynamic_debug: consolidate DEFINE_DYNAMIC_DEBUG_METADATA definitions Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 08/23] dynamic_debug: don't duplicate modname in ddebug_add_module Rasmus Villemoes
2018-10-09 11:19 ` [PATCH v2 09/23] dynamic_debug: use pointer comparison in ddebug_remove_module Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 10/23] dynamic_debug: remove unused EXPORT_SYMBOLs Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 11/23] dynamic_debug: move pr_err from module.c to ddebug_add_module Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 12/23] dynamic_debug: add static inline stub for ddebug_add_module Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 13/23] dynamic_debug: refactor dynamic_pr_debug and friends Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 14/23] btrfs: implement btrfs_debug* in terms of helper macro Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 15/23] ACPI: use proper DYNAMIC_DEBUG_BRANCH macro Rasmus Villemoes
2018-10-10 9:38 ` Rafael J. Wysocki
2018-10-09 11:20 ` [PATCH v2 16/23] ACPI: remove unused __acpi_handle_debug macro Rasmus Villemoes
2018-10-10 9:38 ` Rafael J. Wysocki
2018-10-09 11:20 ` [PATCH v2 17/23] ACPI: implement acpi_handle_debug in terms of _dynamic_func_call Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 18/23] dynamic_debug: introduce accessors for string members of struct _ddebug Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 19/23] dynamic_debug: drop use of bitfields in " Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 20/23] dynamic_debug: introduce CONFIG_DYNAMIC_DEBUG_RELATIVE_POINTERS Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 21/23] x86: jump_label: introduce ASM_STATIC_KEY_INIT_{TRUE,FALSE} Rasmus Villemoes
2018-10-09 11:20 ` [PATCH v2 22/23] x86_64: use relative pointers with dynamic debug Rasmus Villemoes
2018-10-09 11:20 ` Rasmus Villemoes [this message]
2018-10-10 9:37 ` [PATCH v2 00/23] various dynamic_debug patches Rafael J. Wysocki
2018-11-09 23:09 ` [PATCH v3 " Rasmus Villemoes
2018-11-09 23:09 ` [PATCH v3 01/23] linux/device.h: use DYNAMIC_DEBUG_BRANCH in dev_dbg_ratelimited Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 02/23] linux/device.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 03/23] linux/net.h: use DYNAMIC_DEBUG_BRANCH in net_dbg_ratelimited Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 04/23] linux/net.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-11-09 23:22 ` Joe Perches
2018-11-09 23:31 ` Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 05/23] linux/printk.h: use DYNAMIC_DEBUG_BRANCH in pr_debug_ratelimited Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 06/23] linux/printk.h: use unique identifier for each struct _ddebug Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 07/23] dynamic_debug: consolidate DEFINE_DYNAMIC_DEBUG_METADATA definitions Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 08/23] dynamic_debug: don't duplicate modname in ddebug_add_module Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 09/23] dynamic_debug: use pointer comparison in ddebug_remove_module Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 10/23] dynamic_debug: remove unused EXPORT_SYMBOLs Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 11/23] dynamic_debug: move pr_err from module.c to ddebug_add_module Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 12/23] dynamic_debug: add static inline stub for ddebug_add_module Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 13/23] dynamic_debug: refactor dynamic_pr_debug and friends Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 14/23] btrfs: implement btrfs_debug* in terms of helper macro Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 15/23] ACPI: use proper DYNAMIC_DEBUG_BRANCH macro Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 16/23] ACPI: remove unused __acpi_handle_debug macro Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 17/23] ACPI: implement acpi_handle_debug in terms of _dynamic_func_call Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 18/23] dynamic_debug: introduce accessors for string members of struct _ddebug Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 19/23] dynamic_debug: drop use of bitfields in " Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 20/23] dynamic_debug: introduce CONFIG_DYNAMIC_DEBUG_RELATIVE_POINTERS Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 21/23] jump_label: move JUMP_TYPE_* constants to new asm-generic file Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 22/23] x86: jump_label: introduce asm macros STATIC_KEY_INIT{,_TRUE,_FALSE} Rasmus Villemoes
2018-11-09 23:10 ` [PATCH v3 23/23] x86_64: use relative pointers with dynamic debug Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 00/14] various dynamic_debug patches Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 01/14] linux/device.h: use DYNAMIC_DEBUG_BRANCH in dev_dbg_ratelimited Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 02/14] linux/net.h: use DYNAMIC_DEBUG_BRANCH in net_dbg_ratelimited Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 03/14] linux/printk.h: use DYNAMIC_DEBUG_BRANCH in pr_debug_ratelimited Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 04/14] dynamic_debug: consolidate DEFINE_DYNAMIC_DEBUG_METADATA definitions Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 05/14] dynamic_debug: don't duplicate modname in ddebug_add_module Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 06/14] dynamic_debug: use pointer comparison in ddebug_remove_module Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 07/14] dynamic_debug: remove unused EXPORT_SYMBOLs Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 08/14] dynamic_debug: move pr_err from module.c to ddebug_add_module Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 09/14] dynamic_debug: add static inline stub for ddebug_add_module Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 10/14] dynamic_debug: refactor dynamic_pr_debug and friends Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 11/14] btrfs: implement btrfs_debug* in terms of helper macro Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 12/14] ACPI: use proper DYNAMIC_DEBUG_BRANCH macro Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 13/14] ACPI: remove unused __acpi_handle_debug macro Rasmus Villemoes
2019-02-12 21:41 ` [PATCH v4 14/14] ACPI: implement acpi_handle_debug in terms of _dynamic_func_call Rasmus Villemoes
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