__sprint_symbol() might access an invalid pointer when
kallsyms_lookup_buildid() returns a symbol found by
ftrace_mod_address_lookup().
The ftrace lookup function must set both @modname and @modbuildid
the same way as module_address_lookup().
Fixes: 9294523e3768 ("module: add printk formats to add module build ID to stacktraces")
Signed-off-by: Petr Mladek <pmladek@suse.com>
---
include/linux/ftrace.h | 6 ++++--
kernel/kallsyms.c | 4 ++--
kernel/trace/ftrace.c | 5 ++++-
3 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 7ded7df6e9b5..a003cf1b32d0 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -87,11 +87,13 @@ struct ftrace_hash;
defined(CONFIG_DYNAMIC_FTRACE)
int
ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
- unsigned long *off, char **modname, char *sym);
+ unsigned long *off, char **modname,
+ const unsigned char **modbuildid, char *sym);
#else
static inline int
ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
- unsigned long *off, char **modname, char *sym)
+ unsigned long *off, char **modname,
+ const unsigned char **modbuildid, char *sym)
{
return 0;
}
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index efb12b077220..71868a76e9a1 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -378,8 +378,8 @@ static int kallsyms_lookup_buildid(unsigned long addr,
modname, modbuildid, namebuf);
if (!ret)
- ret = ftrace_mod_address_lookup(addr, symbolsize,
- offset, modname, namebuf);
+ ret = ftrace_mod_address_lookup(addr, symbolsize, offset,
+ modname, modbuildid, namebuf);
return ret;
}
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 42bd2ba68a82..11f5096fb60c 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -7678,7 +7678,8 @@ ftrace_func_address_lookup(struct ftrace_mod_map *mod_map,
int
ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
- unsigned long *off, char **modname, char *sym)
+ unsigned long *off, char **modname,
+ const unsigned char **modbuildid, char *sym)
{
struct ftrace_mod_map *mod_map;
int ret = 0;
@@ -7690,6 +7691,8 @@ ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
if (ret) {
if (modname)
*modname = mod_map->mod->name;
+ if (modbuildid)
+ *modbuildid = module_buildid(mod_map->mod);
break;
}
}
--
2.51.1On Wed, Nov 05, 2025 at 03:23:16PM +0100, Petr Mladek wrote:
> __sprint_symbol() might access an invalid pointer when
> kallsyms_lookup_buildid() returns a symbol found by
> ftrace_mod_address_lookup().
>
> The ftrace lookup function must set both @modname and @modbuildid
> the same way as module_address_lookup().
>
> Fixes: 9294523e3768 ("module: add printk formats to add module build ID to stacktraces")
> Signed-off-by: Petr Mladek <pmladek@suse.com>
> ---
> include/linux/ftrace.h | 6 ++++--
> kernel/kallsyms.c | 4 ++--
> kernel/trace/ftrace.c | 5 ++++-
> 3 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
> index 7ded7df6e9b5..a003cf1b32d0 100644
> --- a/include/linux/ftrace.h
> +++ b/include/linux/ftrace.h
> @@ -87,11 +87,13 @@ struct ftrace_hash;
> defined(CONFIG_DYNAMIC_FTRACE)
> int
> ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
> - unsigned long *off, char **modname, char *sym);
> + unsigned long *off, char **modname,
> + const unsigned char **modbuildid, char *sym);
> #else
> static inline int
> ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
> - unsigned long *off, char **modname, char *sym)
> + unsigned long *off, char **modname,
> + const unsigned char **modbuildid, char *sym)
> {
> return 0;
> }
> diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
> index efb12b077220..71868a76e9a1 100644
> --- a/kernel/kallsyms.c
> +++ b/kernel/kallsyms.c
> @@ -378,8 +378,8 @@ static int kallsyms_lookup_buildid(unsigned long addr,
> modname, modbuildid, namebuf);
>
> if (!ret)
> - ret = ftrace_mod_address_lookup(addr, symbolsize,
> - offset, modname, namebuf);
> + ret = ftrace_mod_address_lookup(addr, symbolsize, offset,
> + modname, modbuildid, namebuf);
>
> return ret;
> }
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 42bd2ba68a82..11f5096fb60c 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -7678,7 +7678,8 @@ ftrace_func_address_lookup(struct ftrace_mod_map *mod_map,
>
> int
> ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
> - unsigned long *off, char **modname, char *sym)
> + unsigned long *off, char **modname,
> + const unsigned char **modbuildid, char *sym)
> {
> struct ftrace_mod_map *mod_map;
> int ret = 0;
> @@ -7690,6 +7691,8 @@ ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
> if (ret) {
> if (modname)
> *modname = mod_map->mod->name;
> + if (modbuildid)
> + *modbuildid = module_buildid(mod_map->mod);
> break;
> }
> }
> --
> 2.51.1
>
>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
--
Aaron Tomlin
On Wed, 5 Nov 2025 15:23:16 +0100
Petr Mladek <pmladek@suse.com> wrote:
> __sprint_symbol() might access an invalid pointer when
> kallsyms_lookup_buildid() returns a symbol found by
> ftrace_mod_address_lookup().
>
> The ftrace lookup function must set both @modname and @modbuildid
> the same way as module_address_lookup().
>
> Fixes: 9294523e3768 ("module: add printk formats to add module build ID to stacktraces")
> Signed-off-by: Petr Mladek <pmladek@suse.com>
> ---
> include/linux/ftrace.h | 6 ++++--
> kernel/kallsyms.c | 4 ++--
> kernel/trace/ftrace.c | 5 ++++-
> 3 files changed, 10 insertions(+), 5 deletions(-)
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
-- Steve
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