diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-08 14:12:19 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-08 14:12:19 -0700 |
commit | e74acdf55da6649dd30be5b621a93b71cbe7f3f9 (patch) | |
tree | 6e0e92bd53b4b654551b8198a4e325e76342b3e6 /kernel/module/main.c | |
parent | c8a684e2e110376c58f0bfa30fb3855d1e319670 (diff) | |
parent | 554694ba120b87e39cf732ed632e6a0c52fafb7c (diff) | |
download | lwn-e74acdf55da6649dd30be5b621a93b71cbe7f3f9.tar.gz lwn-e74acdf55da6649dd30be5b621a93b71cbe7f3f9.zip |
Merge tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull module updates from Luis Chamberlain:
"For the 6.0 merge window the modules code shifts to cleanup and minor
fixes effort. This becomes much easier to do and review now due to the
code split to its own directory from effort on the last kernel
release. I expect to see more of this with time and as we expand on
test coverage in the future. The cleanups and fixes come from usual
suspects such as Christophe Leroy and Aaron Tomlin but there are also
some other contributors.
One particular minor fix worth mentioning is from Helge Deller, where
he spotted a *forever* incorrect natural alignment on both ELF section
header tables:
* .altinstructions
* __bug_table sections
A lot of back and forth went on in trying to determine the ill effects
of this misalignment being present for years and it has been
determined there should be no real ill effects unless you have a buggy
exception handler. Helge actually hit one of these buggy exception
handlers on parisc which is how he ended up spotting this issue. When
implemented correctly these paths with incorrect misalignment would
just mean a performance penalty, but given that we are dealing with
alternatives on modules and with the __bug_table (where info regardign
BUG()/WARN() file/line information associated with it is stored) this
really shouldn't be a big deal.
The only other change with mentioning is the kmap() with
kmap_local_page() and my only concern with that was on what is done
after preemption, but the virtual addresses are restored after
preemption. This is only used on module decompression.
This all has sit on linux-next for a while except the kmap stuff which
has been there for 3 weeks"
* tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
module: Replace kmap() with kmap_local_page()
module: Show the last unloaded module's taint flag(s)
module: Use strscpy() for last_unloaded_module
module: Modify module_flags() to accept show_state argument
module: Move module's Kconfig items in kernel/module/
MAINTAINERS: Update file list for module maintainers
module: Use vzalloc() instead of vmalloc()/memset(0)
modules: Ensure natural alignment for .altinstructions and __bug_table sections
module: Increase readability of module_kallsyms_lookup_name()
module: Fix ERRORs reported by checkpatch.pl
module: Add support for default value for module async_probe
Diffstat (limited to 'kernel/module/main.c')
-rw-r--r-- | kernel/module/main.c | 43 |
1 files changed, 30 insertions, 13 deletions
diff --git a/kernel/module/main.c b/kernel/module/main.c index 57fc2821be63..6a477c622544 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -119,7 +119,7 @@ static void mod_update_bounds(struct module *mod) } /* Block module loading/unloading? */ -int modules_disabled = 0; +int modules_disabled; core_param(nomodule, modules_disabled, bint, 0); /* Waiting for a module to finish initializing? */ @@ -524,7 +524,10 @@ static struct module_attribute modinfo_##field = { \ MODINFO_ATTR(version); MODINFO_ATTR(srcversion); -static char last_unloaded_module[MODULE_NAME_LEN+1]; +static struct { + char name[MODULE_NAME_LEN + 1]; + char taints[MODULE_FLAGS_BUF_SIZE]; +} last_unloaded_module; #ifdef CONFIG_MODULE_UNLOAD @@ -694,6 +697,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, { struct module *mod; char name[MODULE_NAME_LEN]; + char buf[MODULE_FLAGS_BUF_SIZE]; int ret, forced = 0; if (!capable(CAP_SYS_MODULE) || modules_disabled) @@ -753,8 +757,9 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, async_synchronize_full(); - /* Store the name of the last unloaded module for diagnostic purposes */ - strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); + /* Store the name and taints of the last unloaded module for diagnostic purposes */ + strscpy(last_unloaded_module.name, mod->name, sizeof(last_unloaded_module.name)); + strscpy(last_unloaded_module.taints, module_flags(mod, buf, false), sizeof(last_unloaded_module.taints)); free_module(mod); /* someone could wait for the module in add_unformed_module() */ @@ -2151,7 +2156,7 @@ static int move_module(struct module *mod, struct load_info *info) #ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC /* Do the allocs. */ - ptr = vmalloc(mod->data_layout.size); + ptr = vzalloc(mod->data_layout.size); /* * The pointer to this block is stored in the module structure * which is inside the block. Just mark it as not being a @@ -2164,7 +2169,6 @@ static int move_module(struct module *mod, struct load_info *info) return -ENOMEM; } - memset(ptr, 0, mod->data_layout.size); mod->data_layout.base = ptr; #endif /* Transfer each section which specifies SHF_ALLOC */ @@ -2423,6 +2427,12 @@ static void do_free_init(struct work_struct *w) } } +#undef MODULE_PARAM_PREFIX +#define MODULE_PARAM_PREFIX "module." +/* Default value for module->async_probe_requested */ +static bool async_probe; +module_param(async_probe, bool, 0644); + /* * This is where the real work happens. * @@ -2643,7 +2653,8 @@ static int unknown_module_param_cb(char *param, char *val, const char *modname, int ret; if (strcmp(param, "async_probe") == 0) { - mod->async_probe_requested = true; + if (strtobool(val, &mod->async_probe_requested)) + mod->async_probe_requested = true; return 0; } @@ -2810,6 +2821,8 @@ static int load_module(struct load_info *info, const char __user *uargs, if (err) goto bug_cleanup; + mod->async_probe_requested = async_probe; + /* Module is ready to execute: parsing args may do that. */ after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, -32768, 32767, mod, @@ -2984,24 +2997,27 @@ static void cfi_cleanup(struct module *mod) } /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ -char *module_flags(struct module *mod, char *buf) +char *module_flags(struct module *mod, char *buf, bool show_state) { int bx = 0; BUG_ON(mod->state == MODULE_STATE_UNFORMED); + if (!mod->taints && !show_state) + goto out; if (mod->taints || mod->state == MODULE_STATE_GOING || mod->state == MODULE_STATE_COMING) { buf[bx++] = '('; bx += module_flags_taint(mod->taints, buf + bx); /* Show a - for module-is-being-unloaded */ - if (mod->state == MODULE_STATE_GOING) + if (mod->state == MODULE_STATE_GOING && show_state) buf[bx++] = '-'; /* Show a + for module-is-being-loaded */ - if (mod->state == MODULE_STATE_COMING) + if (mod->state == MODULE_STATE_COMING && show_state) buf[bx++] = '+'; buf[bx++] = ')'; } +out: buf[bx] = '\0'; return buf; @@ -3134,12 +3150,13 @@ void print_modules(void) list_for_each_entry_rcu(mod, &modules, list) { if (mod->state == MODULE_STATE_UNFORMED) continue; - pr_cont(" %s%s", mod->name, module_flags(mod, buf)); + pr_cont(" %s%s", mod->name, module_flags(mod, buf, true)); } print_unloaded_tainted_modules(); preempt_enable(); - if (last_unloaded_module[0]) - pr_cont(" [last unloaded: %s]", last_unloaded_module); + if (last_unloaded_module.name[0]) + pr_cont(" [last unloaded: %s%s]", last_unloaded_module.name, + last_unloaded_module.taints); pr_cont("\n"); } |