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[v5,03/15] Escape names used in symbol whitelisting regex.

Message ID 20200504164520.93024-1-gprocida@google.com
State Committed
Headers
Series None |

Commit Message

Giuliano Procida May 4, 2020, 4:45 p.m. UTC 
  There is the theoretical possibility that symbols may contain special
regex characters like '.' and '$'. This patch ensures all such
characters in symbol names are escaped before they are added to the
whitelisting regex.

	* include/regex.h (escape): New string reference holder
	class. (operator<<): Declaration of std::ostream,
	regex::escape overload.
	* include/regex.cc (operator<<): New std::ostream,
	regex::escape overload that outputs regex-escaped strings.
	* src/abg-tools-utils.cc
	(gen_suppr_spec_from_kernel_abi_whitelists): Make sure any
	special regex characters in symbol names are escaped.

Reviewed-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Giuliano Procida <gprocida@google.com>
---
 include/abg-regex.h | 10 ++++++++++
 src/abg-regex.cc    | 28 ++++++++++++++++++++++++++--
 2 files changed, 36 insertions(+), 2 deletions(-)

Comments

Dodji Seketeli May 11, 2020, 1:59 p.m. UTC | #1 
Giuliano Procida <gprocida@google.com> a ?crit:

> There is the theoretical possibility that symbols may contain special
> regex characters like '.' and '$'. This patch ensures all such
> characters in symbol names are escaped before they are added to the
> whitelisting regex.
>
> 	* include/regex.h (escape): New string reference holder
> 	class. (operator<<): Declaration of std::ostream,
> 	regex::escape overload.
> 	* include/regex.cc (operator<<): New std::ostream,
> 	regex::escape overload that outputs regex-escaped strings.
> 	* src/abg-tools-utils.cc
> 	(gen_suppr_spec_from_kernel_abi_whitelists): Make sure any
> 	special regex characters in symbol names are escaped.

Applied to master, thanks!

Cheers,
diff mbox series

Patch

diff --git a/include/abg-regex.h b/include/abg-regex.h
index d39ada46..164083cc 100644
--- a/include/abg-regex.h
+++ b/include/abg-regex.h
@@ -58,6 +58,16 @@  struct regex_t_deleter
   }
 };//end struct regex_deleter
 
+/// A class to hold a reference to a string to regex escape.
+struct escape
+{
+  escape(const std::string& str) : ref(str) { }
+  const std::string& ref;
+};
+
+std::ostream&
+operator<<(std::ostream& os, const escape& esc);
+
 std::string
 generate_from_strings(const std::vector<std::string>& strs);
 
diff --git a/src/abg-regex.cc b/src/abg-regex.cc
index 0451d111..59f56deb 100644
--- a/src/abg-regex.cc
+++ b/src/abg-regex.cc
@@ -24,6 +24,7 @@ 
 ///
 
 #include <sstream>
+#include <ostream>
 
 #include "abg-regex.h"
 #include "abg-sptr-utils.h"
@@ -57,6 +58,29 @@  sptr_utils::build_sptr<regex_t>()
 namespace regex
 {
 
+/// Escape regex special charaters in input string.
+///
+/// @param os the output stream being written to.
+///
+/// @param esc the regex_escape object holding a reference to the string
+/// needing to be escaped.
+///
+/// @return the output stream.
+std::ostream&
+operator<<(std::ostream& os, const escape& esc)
+{
+  // ']' and '}' are only conditionally special, so could be removed.
+  static const std::string specials = "^.[]$()|*+?{}\\";
+  const std::string& str = esc.ref;
+  for (std::string::const_iterator i = str.begin(); i != str.end(); ++i)
+    {
+      if (specials.find(*i) != std::string::npos)
+	os << '\\';
+      os << *i;
+    }
+  return os;
+}
+
 /// Generate a regex pattern equivalent to testing set membership.
 ///
 /// A string will match the resulting pattern regex, if and only if it
@@ -73,9 +97,9 @@  generate_from_strings(const std::vector<std::string>& strs)
     return "^_^";
   std::ostringstream os;
   std::vector<std::string>::const_iterator i = strs.begin();
-  os << "^(" << *i++;
+  os << "^(" << escape(*i++);
   while (i != strs.end())
-    os << "|" << *i++;
+    os << "|" << escape(*i++);
   os << ")$";
   return os.str();
 }