Hey Aaron, I have added the wildcard handling for the PR29997. From 0c95ce19272d6e13abf6f41c4ae29b6aa925ca20 Mon Sep 17 00:00:00 2001 From: Di Chen Date: Sun, 5 Nov 2023 11:23:50 +0800 Subject: [PATCH] PR29997: Fix the symbol aliases search failure when symbol version is missing After calling module_info::update_symtab, function aliases will be populated. Then the updated symtab will be used for symbol searching. For the _IO_new_fopen familty with the aliases: $ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440 247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@ @GLIBC_2.2.5 1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@ @GLIBC_2.2.5 1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@ @GLIBC_2.2.5 1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_fopen64 3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 __new_fopen 4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16 _IO_new_fopen 5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64 7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@ @GLIBC_2.2.5 7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 _IO_fopen@ @GLIBC_2.2.5 a) fopen@@GLIBC_2.2.5 exists in the updated symtab b) fopen does not exist in the updated symtab This PR is to add a version info padding when symbol cannot be found in the updated symtab. Signed-off-by: Di Chen --- dwflpp.cxx | 44 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 43 insertions(+), 1 deletion(-) diff --git a/dwflpp.cxx b/dwflpp.cxx index 9fccca0a9..044b0ca97 100644 --- a/dwflpp.cxx +++ b/dwflpp.cxx @@ -1055,6 +1055,15 @@ dwflpp::iterate_over_functions(int (*callback)(Dwarf_Die*, void*), } auto range = v->equal_range(function); + // version padding if the symbol is not found + if (range.first == range.second) + { + std::string function_with_ver = function + "@"; + for (auto it = v->begin(); it != v->end(); ++it) + if (it->first.find(function_with_ver) == 0) + function_with_ver = it->first; + range = v->equal_range(function_with_ver); + } if (range.first != range.second) { for (auto it = range.first; it != range.second; ++it) @@ -1098,7 +1107,10 @@ dwflpp::iterate_over_functions(int (*callback)(Dwarf_Die*, void*), if (pending_interrupts) return DWARF_CB_ABORT; const string& func_name = it->first; Dwarf_Die& die = it->second; - if (function_name_matches_pattern (func_name, function)) + + // version padding if the pattern is not matched + if ((function_name_matches_pattern (func_name, function)) || + (function_name_matches_pattern (func_name, function + "@*"))) { if (sess.verbose > 4) clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(), @@ -1141,6 +1153,15 @@ dwflpp::iterate_single_function(int (*callback)(Dwarf_Die*, void*), } auto range = v->equal_range(function); + // version padding if the symbol is not found + if (range.first == range.second) + { + std::string function_with_ver = function + "@"; + for (auto it = v->begin(); it != v->end(); ++it) + if (it->first.find(function_with_ver) == 0) + function_with_ver = it->first; + range = v->equal_range(function_with_ver); + } if (range.first != range.second) { for (auto it = range.first; it != range.second; ++it) @@ -1158,6 +1179,27 @@ dwflpp::iterate_single_function(int (*callback)(Dwarf_Die*, void*), if (rc != DWARF_CB_OK) break; } } + else if (name_has_wildcard (function)) + { + for (auto it = v->begin(); it != v->end(); ++it) + { + if (pending_interrupts) return DWARF_CB_ABORT; + const string& func_name = it->first; + Dwarf_Die& die = it->second; + + // version padding if the pattern is not matched + if ((function_name_matches_pattern (func_name, function)) || + (function_name_matches_pattern (func_name, function + "@*"))) + { + if (sess.verbose > 4) + clog << _F("function cache %s:%s match %s vs %s", module_name.c_str(), + cu_name().c_str(), func_name.c_str(), function.c_str()) << endl; + + rc = (*callback)(& die, data); + if (rc != DWARF_CB_OK) break; + } + } + } // undo the focus_on_cu this->cu = NULL; -- 2.41.0 On Tue, Nov 21, 2023 at 12:05 AM Aaron Merey wrote: > Hi Di, > > Thanks for working on this. > > On Sun, Nov 5, 2023 at 12:00 AM Di Chen via Systemtap > wrote: > > > > From 9273dc95658b109f048e4ec9b0fcde96e34f3419 Mon Sep 17 00:00:00 2001 > > From: Di Chen > > Date: Sun, 5 Nov 2023 11:23:50 +0800 > > Subject: [PATCH] PR29997: Fix the symbol aliases search failure when > symbol > > version is missing > > > > After calling module_info::update_symtab, function aliases will be > > populated. Then the updated symtab will be used for symbol searching. > > > > For the _IO_new_fopen familty with the aliases: > > > > $ eu-readelf -s /lib64/libc.so.6 | grep 0000000000077440 > > 247: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64@ > > @GLIBC_2.2.5 > > 1014: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@ > > @GLIBC_2.2.5 > > 1028: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 > _IO_fopen@ > > @GLIBC_2.2.5 > > 1556: 0000000000077440 14 FUNC LOCAL DEFAULT 16 > _IO_fopen64 > > 3471: 0000000000077440 14 FUNC LOCAL DEFAULT 16 > __new_fopen > > 4765: 0000000000077440 14 FUNC LOCAL DEFAULT 16 > > _IO_new_fopen > > 5110: 0000000000077440 14 FUNC WEAK DEFAULT 16 fopen64 > > 7198: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 fopen@ > > @GLIBC_2.2.5 > > 7433: 0000000000077440 14 FUNC GLOBAL DEFAULT 16 > _IO_fopen@ > > @GLIBC_2.2.5 > > > > a) fopen@@GLIBC_2.2.5 exists in the updated symtab > > b) fopen does not exist in the updated symtab > > > > This PR is to add a version info padding when symbol cannot be found in > > the updated symtab. > > > > Signed-off-by: Di Chen > > --- > > dwflpp.cxx | 18 ++++++++++++++++++ > > 1 file changed, 18 insertions(+) > > > > diff --git a/dwflpp.cxx b/dwflpp.cxx > > index a4f66440f..22e1479c9 100644 > > --- a/dwflpp.cxx > > +++ b/dwflpp.cxx > > @@ -1052,6 +1052,15 @@ dwflpp::iterate_over_functions(int > > (*callback)(Dwarf_Die*, void*), > > } > > > > auto range = v->equal_range(function); > > + // version info padding if the symbol is not found > > + if (range.first == range.second) > > + { > > + std::string function_with_ver = function + "@"; > > + for (auto it = v->begin(); it != v->end(); ++it) > > + if (it->first.find(function_with_ver) == 0) > > + function_with_ver = it->first; > > + range = v->equal_range(function_with_ver); > > + } > > This fixes the bug for function names without wildcards. However > the bug can still be reproduced using function names with wildcards. > For example the following command incorrectly returns no results: > > $ stap -L 'process("/lib64/libc.so.6").function("fo*en")' > > We'll need additional '@' handling in the section of > dwflpp::iterate_over_functions that matches wildcards. > > > if (range.first != range.second) > > { > > for (auto it = range.first; it != range.second; ++it) > > @@ -1138,6 +1147,15 @@ dwflpp::iterate_single_function(int > > (*callback)(Dwarf_Die*, void*), > > } > > > > auto range = v->equal_range(function); > > + // version info padding if the symbol is not found > > + if (range.first == range.second) > > + { > > + std::string function_with_ver = function + "@"; > > + for (auto it = v->begin(); it != v->end(); ++it) > > + if (it->first.find(function_with_ver) == 0) > > + function_with_ver = it->first; > > + range = v->equal_range(function_with_ver); > > + } > > if (range.first != range.second) > > { > > for (auto it = range.first; it != range.second; ++it) > > -- > > 2.41.0 > > Aaron > >