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From: Petr Mladek <pmladek@suse.com>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	"Tobin C . Harding" <me@tobin.cc>, Joe Perches <joe@perches.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Michal Hocko <mhocko@suse.cz>,
	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
	linux-kernel@vger.kernel.org, Petr Mladek <pmladek@suse.com>
Subject: [PATCH v7 01/10] vsprintf: Shuffle restricted_pointer()
Date: Wed, 17 Apr 2019 13:53:41 +0200	[thread overview]
Message-ID: <20190417115350.20479-2-pmladek@suse.com> (raw)
In-Reply-To: <20190417115350.20479-1-pmladek@suse.com>

This is just a preparation step for further changes.

The patch does not change the code.

Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 lib/vsprintf.c | 98 +++++++++++++++++++++++++++++-----------------------------
 1 file changed, 49 insertions(+), 49 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 791b6fa36905..eb7b4a06e1f0 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -717,6 +717,55 @@ static char *ptr_to_id(char *buf, char *end, const void *ptr,
 	return pointer_string(buf, end, (const void *)hashval, spec);
 }
 
+int kptr_restrict __read_mostly;
+
+static noinline_for_stack
+char *restricted_pointer(char *buf, char *end, const void *ptr,
+			 struct printf_spec spec)
+{
+	switch (kptr_restrict) {
+	case 0:
+		/* Always print %pK values */
+		break;
+	case 1: {
+		const struct cred *cred;
+
+		/*
+		 * kptr_restrict==1 cannot be used in IRQ context
+		 * because its test for CAP_SYSLOG would be meaningless.
+		 */
+		if (in_irq() || in_serving_softirq() || in_nmi()) {
+			if (spec.field_width == -1)
+				spec.field_width = 2 * sizeof(ptr);
+			return string(buf, end, "pK-error", spec);
+		}
+
+		/*
+		 * Only print the real pointer value if the current
+		 * process has CAP_SYSLOG and is running with the
+		 * same credentials it started with. This is because
+		 * access to files is checked at open() time, but %pK
+		 * checks permission at read() time. We don't want to
+		 * leak pointer values if a binary opens a file using
+		 * %pK and then elevates privileges before reading it.
+		 */
+		cred = current_cred();
+		if (!has_capability_noaudit(current, CAP_SYSLOG) ||
+		    !uid_eq(cred->euid, cred->uid) ||
+		    !gid_eq(cred->egid, cred->gid))
+			ptr = NULL;
+		break;
+	}
+	case 2:
+	default:
+		/* Always print 0's for %pK */
+		ptr = NULL;
+		break;
+	}
+
+	return pointer_string(buf, end, ptr, spec);
+}
+
 static noinline_for_stack
 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 		  const char *fmt)
@@ -1476,55 +1525,6 @@ char *uuid_string(char *buf, char *end, const u8 *addr,
 	return string(buf, end, uuid, spec);
 }
 
-int kptr_restrict __read_mostly;
-
-static noinline_for_stack
-char *restricted_pointer(char *buf, char *end, const void *ptr,
-			 struct printf_spec spec)
-{
-	switch (kptr_restrict) {
-	case 0:
-		/* Always print %pK values */
-		break;
-	case 1: {
-		const struct cred *cred;
-
-		/*
-		 * kptr_restrict==1 cannot be used in IRQ context
-		 * because its test for CAP_SYSLOG would be meaningless.
-		 */
-		if (in_irq() || in_serving_softirq() || in_nmi()) {
-			if (spec.field_width == -1)
-				spec.field_width = 2 * sizeof(ptr);
-			return string(buf, end, "pK-error", spec);
-		}
-
-		/*
-		 * Only print the real pointer value if the current
-		 * process has CAP_SYSLOG and is running with the
-		 * same credentials it started with. This is because
-		 * access to files is checked at open() time, but %pK
-		 * checks permission at read() time. We don't want to
-		 * leak pointer values if a binary opens a file using
-		 * %pK and then elevates privileges before reading it.
-		 */
-		cred = current_cred();
-		if (!has_capability_noaudit(current, CAP_SYSLOG) ||
-		    !uid_eq(cred->euid, cred->uid) ||
-		    !gid_eq(cred->egid, cred->gid))
-			ptr = NULL;
-		break;
-	}
-	case 2:
-	default:
-		/* Always print 0's for %pK */
-		ptr = NULL;
-		break;
-	}
-
-	return pointer_string(buf, end, ptr, spec);
-}
-
 static noinline_for_stack
 char *netdev_bits(char *buf, char *end, const void *addr,
 		  struct printf_spec spec,  const char *fmt)
-- 
2.16.4


  reply	other threads:[~2019-04-17 11:54 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-17 11:53 [PATCH v7 00/10] vsprintf: Prevent silent crashes and consolidate error handling Petr Mladek
2019-04-17 11:53 ` Petr Mladek [this message]
2019-04-17 11:53 ` [PATCH v7 02/10] vsprintf: Consistent %pK handling for kptr_restrict == 0 Petr Mladek
2019-04-17 13:44   ` Steven Rostedt
2019-04-17 11:53 ` [PATCH v7 03/10] vsprintf: Do not check address of well-known strings Petr Mladek
2019-04-17 11:53 ` [PATCH v7 04/10] vsprintf: Factor out %p[iI] handler as ip_addr_string() Petr Mladek
2019-04-17 11:53 ` [PATCH v7 05/10] vsprintf: Factor out %pV handler as va_format() Petr Mladek
2019-04-17 11:53 ` [PATCH v7 06/10] vsprintf: Factor out %pO handler as kobject_string() Petr Mladek
2019-04-17 11:53 ` [PATCH v7 07/10] vsprintf: Consolidate handling of unknown pointer specifiers Petr Mladek
2019-04-18 14:34   ` Sergey Senozhatsky
2019-04-18 14:43   ` Sergey Senozhatsky
2019-04-18 14:50   ` Sergey Senozhatsky
2019-06-25 10:59   ` Geert Uytterhoeven
2019-06-26 10:46     ` Petr Mladek
2019-06-26 11:16       ` Geert Uytterhoeven
2019-04-17 11:53 ` [PATCH v7 08/10] vsprintf: Prevent crash when dereferencing invalid pointers Petr Mladek
2019-04-17 11:53 ` [PATCH v7 09/10] vsprintf: Avoid confusion between invalid address and value Petr Mladek
2019-04-17 11:53 ` [PATCH v7 10/10] vsprintf: Limit the length of inlined error messages Petr Mladek
2019-04-19  1:51 ` [PATCH v7 00/10] vsprintf: Prevent silent crashes and consolidate error handling Sergey Senozhatsky
2019-04-24 13:53   ` Petr Mladek
2019-04-26 13:02     ` Andy Shevchenko
2019-04-26 14:27       ` Petr Mladek

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