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authorLinus Torvalds <torvalds@linux-foundation.org>2026-02-12 12:13:01 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2026-02-12 12:13:01 -0800
commit136114e0abf03005e182d75761ab694648e6d388 (patch)
tree05c61b103fc9cb72a7cae99680a4b524347e9616 /kernel/kallsyms.c
parent4cff5c05e076d2ee4e34122aa956b84a2eaac587 (diff)
parent0dddf20b4fd4afd59767acc144ad4da60259f21f (diff)
downloadlinux-next-136114e0abf03005e182d75761ab694648e6d388.tar.gz
linux-next-136114e0abf03005e182d75761ab694648e6d388.zip
Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves disk space by teaching ocfs2 to reclaim suballocator block group space (Heming Zhao) - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the ARRAY_END() macro and uses it in various places (Alejandro Colomar) - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the page size (Pnina Feder) - "kallsyms: Prevent invalid access when showing module buildid" cleans up kallsyms code related to module buildid and fixes an invalid access crash when printing backtraces (Petr Mladek) - "Address page fault in ima_restore_measurement_list()" fixes a kexec-related crash that can occur when booting the second-stage kernel on x86 (Harshit Mogalapalli) - "kho: ABI headers and Documentation updates" updates the kexec handover ABI documentation (Mike Rapoport) - "Align atomic storage" adds the __aligned attribute to atomic_t and atomic64_t definitions to get natural alignment of both types on csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain) - "kho: clean up page initialization logic" simplifies the page initialization logic in kho_restore_page() (Pratyush Yadav) - "Unload linux/kernel.h" moves several things out of kernel.h and into more appropriate places (Yury Norov) - "don't abuse task_struct.group_leader" removes the usage of ->group_leader when it is "obviously unnecessary" (Oleg Nesterov) - "list private v2 & luo flb" adds some infrastructure improvements to the live update orchestrator (Pasha Tatashin) * tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits) watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency procfs: fix missing RCU protection when reading real_parent in do_task_stat() watchdog/softlockup: fix sample ring index wrap in need_counting_irqs() kcsan, compiler_types: avoid duplicate type issues in BPF Type Format kho: fix doc for kho_restore_pages() tests/liveupdate: add in-kernel liveupdate test liveupdate: luo_flb: introduce File-Lifecycle-Bound global state liveupdate: luo_file: Use private list list: add kunit test for private list primitives list: add primitives for private list manipulations delayacct: fix uapi timespec64 definition panic: add panic_force_cpu= parameter to redirect panic to a specific CPU netclassid: use thread_group_leader(p) in update_classid_task() RDMA/umem: don't abuse current->group_leader drm/pan*: don't abuse current->group_leader drm/amd: kill the outdated "Only the pthreads threading model is supported" checks drm/amdgpu: don't abuse current->group_leader android/binder: use same_thread_group(proc->tsk, current) in binder_mmap() android/binder: don't abuse current->group_leader kho: skip memoryless NUMA nodes when reserving scratch areas ...
Diffstat (limited to 'kernel/kallsyms.c')
-rw-r--r--kernel/kallsyms.c73
1 files changed, 54 insertions, 19 deletions
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 6125724aadb1..aec2f06858af 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -347,7 +347,7 @@ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize,
return 1;
}
return !!module_address_lookup(addr, symbolsize, offset, NULL, NULL, namebuf) ||
- !!__bpf_address_lookup(addr, symbolsize, offset, namebuf);
+ !!bpf_address_lookup(addr, symbolsize, offset, namebuf);
}
static int kallsyms_lookup_buildid(unsigned long addr,
@@ -357,8 +357,21 @@ static int kallsyms_lookup_buildid(unsigned long addr,
{
int ret;
- namebuf[KSYM_NAME_LEN - 1] = 0;
+ /*
+ * kallsyms_lookus() returns pointer to namebuf on success and
+ * NULL on error. But some callers ignore the return value.
+ * Instead they expect @namebuf filled either with valid
+ * or empty string.
+ */
namebuf[0] = 0;
+ /*
+ * Initialize the module-related return values. They are not set
+ * when the symbol is in vmlinux or it is a bpf address.
+ */
+ if (modname)
+ *modname = NULL;
+ if (modbuildid)
+ *modbuildid = NULL;
if (is_ksym_addr(addr)) {
unsigned long pos;
@@ -367,10 +380,6 @@ static int kallsyms_lookup_buildid(unsigned long addr,
/* Grab name */
kallsyms_expand_symbol(get_symbol_offset(pos),
namebuf, KSYM_NAME_LEN);
- if (modname)
- *modname = NULL;
- if (modbuildid)
- *modbuildid = NULL;
return strlen(namebuf);
}
@@ -379,12 +388,11 @@ static int kallsyms_lookup_buildid(unsigned long addr,
ret = module_address_lookup(addr, symbolsize, offset,
modname, modbuildid, namebuf);
if (!ret)
- ret = bpf_address_lookup(addr, symbolsize,
- offset, modname, namebuf);
+ ret = bpf_address_lookup(addr, symbolsize, offset, 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;
}
@@ -428,6 +436,37 @@ int lookup_symbol_name(unsigned long addr, char *symname)
return lookup_module_symbol_name(addr, symname);
}
+#ifdef CONFIG_STACKTRACE_BUILD_ID
+
+static int append_buildid(char *buffer, const char *modname,
+ const unsigned char *buildid)
+{
+ if (!modname)
+ return 0;
+
+ if (!buildid) {
+ pr_warn_once("Undefined buildid for the module %s\n", modname);
+ return 0;
+ }
+
+ /* build ID should match length of sprintf */
+#ifdef CONFIG_MODULES
+ static_assert(sizeof(typeof_member(struct module, build_id)) == 20);
+#endif
+
+ return sprintf(buffer, " %20phN", buildid);
+}
+
+#else /* CONFIG_STACKTRACE_BUILD_ID */
+
+static int append_buildid(char *buffer, const char *modname,
+ const unsigned char *buildid)
+{
+ return 0;
+}
+
+#endif /* CONFIG_STACKTRACE_BUILD_ID */
+
/* Look up a kernel symbol and return it in a text buffer. */
static int __sprint_symbol(char *buffer, unsigned long address,
int symbol_offset, int add_offset, int add_buildid)
@@ -437,6 +476,9 @@ static int __sprint_symbol(char *buffer, unsigned long address,
unsigned long offset, size;
int len;
+ /* Prevent module removal until modname and modbuildid are printed */
+ guard(rcu)();
+
address += symbol_offset;
len = kallsyms_lookup_buildid(address, &size, &offset, &modname, &buildid,
buffer);
@@ -450,15 +492,8 @@ static int __sprint_symbol(char *buffer, unsigned long address,
if (modname) {
len += sprintf(buffer + len, " [%s", modname);
-#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
- if (add_buildid && buildid) {
- /* build ID should match length of sprintf */
-#if IS_ENABLED(CONFIG_MODULES)
- static_assert(sizeof(typeof_member(struct module, build_id)) == 20);
-#endif
- len += sprintf(buffer + len, " %20phN", buildid);
- }
-#endif
+ if (add_buildid)
+ len += append_buildid(buffer + len, modname, buildid);
len += sprintf(buffer + len, "]");
}