| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20250619145659.1377970-9-alexandre.chartre@oracle.com>
Date: Thu, 19 Jun 2025 16:56:50 +0200
From: Alexandre Chartre <alexandre.chartre@...cle.com>
To: linux-kernel@...r.kernel.org, mingo@...nel.org, jpoimboe@...nel.org,
peterz@...radead.org
Cc: alexandre.chartre@...cle.com
Subject: [RFC PATCH v2 08/17] objtool: Disassemble instruction on warning or backtrace
When an instruction warning (WARN_INSN) or backtrace (BT_INSN) is issued,
disassemble the instruction to provide more context.
Signed-off-by: Alexandre Chartre <alexandre.chartre@...cle.com>
---
tools/objtool/check.c | 36 ++++++++++++++++++++++-----
tools/objtool/disas.c | 5 ++--
tools/objtool/include/objtool/check.h | 2 ++
tools/objtool/include/objtool/disas.h | 13 ++++++++++
tools/objtool/include/objtool/warn.h | 16 ++++++++----
5 files changed, 58 insertions(+), 14 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index a4d0a6c62bc0..beaafa1f0323 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -4581,11 +4581,34 @@ static void free_insns(struct objtool_file *file)
free(chunk->addr);
}
+static struct disas_context *objtool_disas_ctx;
+
+const char *objtool_disas_insn(struct instruction *insn)
+{
+ struct disas_context *dctx = objtool_disas_ctx;
+
+ if (!dctx)
+ return "";
+
+ disas_insn(dctx, insn);
+ return disas_result(dctx);
+}
+
int check(struct objtool_file *file)
{
- struct disas_context *disas_ctx;
+ struct disas_context *disas_ctx = NULL;
int ret = 0, warnings = 0;
+ /*
+ * If the verbose or backtrace option is used then we need a
+ * disassembly context to disassemble instruction or function
+ * on warning or backtrace.
+ */
+ if (opts.verbose || opts.backtrace) {
+ disas_ctx = disas_context_create(file);
+ objtool_disas_ctx = disas_ctx;
+ }
+
arch_initial_func_cfi_state(&initial_func_cfi);
init_cfi_state(&init_cfi);
init_cfi_state(&func_cfi);
@@ -4711,11 +4734,12 @@ int check(struct objtool_file *file)
if (opts.werror && warnings)
WARN("%d warning(s) upgraded to errors", warnings);
print_args();
- disas_ctx = disas_context_create(file);
- if (disas_ctx) {
- disas_warned_funcs(disas_ctx);
- disas_context_destroy(disas_ctx);
- }
+ disas_warned_funcs(disas_ctx);
+ }
+
+ if (disas_ctx) {
+ disas_context_destroy(disas_ctx);
+ objtool_disas_ctx = NULL;
}
free_insns(file);
diff --git a/tools/objtool/disas.c b/tools/objtool/disas.c
index fbec062f40eb..3831e46e0f35 100644
--- a/tools/objtool/disas.c
+++ b/tools/objtool/disas.c
@@ -256,7 +256,7 @@ void disas_context_destroy(struct disas_context *dctx)
free(dctx);
}
-static char *disas_result(struct disas_context *dctx)
+char *disas_result(struct disas_context *dctx)
{
return dctx->result;
}
@@ -264,8 +264,7 @@ static char *disas_result(struct disas_context *dctx)
/*
* Disassemble a single instruction. Return the size of the instruction.
*/
-static size_t disas_insn(struct disas_context *dctx,
- struct instruction *insn)
+size_t disas_insn(struct disas_context *dctx, struct instruction *insn)
{
disassembler_ftype disasm = dctx->disassembler;
struct disassemble_info *dinfo = &dctx->info;
diff --git a/tools/objtool/include/objtool/check.h b/tools/objtool/include/objtool/check.h
index 4adbcd760c6f..f3ea144d4746 100644
--- a/tools/objtool/include/objtool/check.h
+++ b/tools/objtool/include/objtool/check.h
@@ -139,4 +139,6 @@ struct instruction *next_insn_same_sec(struct objtool_file *file, struct instruc
insn && insn->offset < sym->offset + sym->len; \
insn = next_insn_same_sec(file, insn))
+const char *objtool_disas_insn(struct instruction *insn);
+
#endif /* _CHECK_H */
diff --git a/tools/objtool/include/objtool/disas.h b/tools/objtool/include/objtool/disas.h
index 3ec3ce2e4e6f..1aee1fbe0bb9 100644
--- a/tools/objtool/include/objtool/disas.h
+++ b/tools/objtool/include/objtool/disas.h
@@ -17,6 +17,8 @@ void disas_warned_funcs(struct disas_context *dctx);
int disas_info_init(struct disassemble_info *dinfo,
int arch, int mach32, int mach64,
const char *options);
+size_t disas_insn(struct disas_context *dctx, struct instruction *insn);
+char *disas_result(struct disas_context *dctx);
#else /* DISAS */
@@ -38,6 +40,17 @@ static inline int disas_info_init(struct disassemble_info *dinfo,
return -1;
}
+static inline size_t disas_insn(struct disas_context *dctx,
+ struct instruction *insn)
+{
+ return -1;
+}
+
+static inline char *disas_result(struct disas_context *dctx)
+{
+ return NULL;
+}
+
#endif /* DISAS */
#endif /* _DISAS_H */
diff --git a/tools/objtool/include/objtool/warn.h b/tools/objtool/include/objtool/warn.h
index d89e6ae69143..f001233b27df 100644
--- a/tools/objtool/include/objtool/warn.h
+++ b/tools/objtool/include/objtool/warn.h
@@ -89,9 +89,11 @@ static inline char *offstr(struct section *sec, unsigned long offset)
#define WARN_INSN(insn, format, ...) \
({ \
struct instruction *_insn = (insn); \
- if (!_insn->sym || !_insn->sym->warned) \
+ if (!_insn->sym || !_insn->sym->warned) { \
WARN_FUNC(_insn->sec, _insn->offset, format, \
##__VA_ARGS__); \
+ BT_INSN(_insn, ""); \
+ } \
if (_insn->sym) \
_insn->sym->warned = 1; \
})
@@ -99,10 +101,14 @@ static inline char *offstr(struct section *sec, unsigned long offset)
#define BT_INSN(insn, format, ...) \
({ \
if (opts.verbose || opts.backtrace) { \
- struct instruction *_insn = (insn); \
- char *_str = offstr(_insn->sec, _insn->offset); \
- WARN(" %s: " format, _str, ##__VA_ARGS__); \
- free(_str); \
+ struct instruction *__insn = (insn); \
+ char *_str = offstr(__insn->sec, __insn->offset); \
+ const char *_istr = objtool_disas_insn(__insn); \
+ int _len; \
+ _len = snprintf(NULL, 0, " %s: " format, _str, ##__VA_ARGS__); \
+ _len = (_len < 50) ? 50 - _len : 0; \
+ WARN(" %s: " format " %*s%s", _str, ##__VA_ARGS__, _len, "", _istr); \
+ free(_str); \
} \
})
--
2.43.5
Powered by blists - more mailing lists