--- /dev/null
+From a6846234f45801441f0e31a8b37f901ef0abd2df Mon Sep 17 00:00:00 2001
+From: James Morse <james.morse@arm.com>
+Date: Tue, 1 Aug 2023 14:54:09 +0000
+Subject: ARM: module: Use module_init_layout_section() to spot init sections
+
+From: James Morse <james.morse@arm.com>
+
+commit a6846234f45801441f0e31a8b37f901ef0abd2df upstream.
+
+Today module_frob_arch_sections() spots init sections from their
+'init' prefix, and uses this to keep the init PLTs separate from the rest.
+
+get_module_plt() uses within_module_init() to determine if a
+location is in the init text or not, but this depends on whether
+core code thought this was an init section.
+
+Naturally the logic is different.
+
+module_init_layout_section() groups the init and exit text together if
+module unloading is disabled, as the exit code will never run. The result
+is kernels with this configuration can't load all their modules because
+there are not enough PLTs for the combined init+exit section.
+
+A previous patch exposed module_init_layout_section(), use that so the
+logic is the same.
+
+Fixes: 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()")
+Cc: stable@vger.kernel.org
+Signed-off-by: James Morse <james.morse@arm.com>
+Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/arm/kernel/module-plts.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/arm/kernel/module-plts.c
++++ b/arch/arm/kernel/module-plts.c
+@@ -256,7 +256,7 @@ int module_frob_arch_sections(Elf_Ehdr *
+ /* sort by type and symbol index */
+ sort(rels, numrels, sizeof(Elf32_Rel), cmp_rel, NULL);
+
+- if (strncmp(secstrings + dstsec->sh_name, ".init", 5) != 0)
++ if (!module_init_layout_section(secstrings + dstsec->sh_name))
+ core_plts += count_plts(syms, dstsec->sh_addr, rels,
+ numrels, s->sh_info);
+ else
--- /dev/null
+From 60a0aab7463ee69296692d980b96510ccce3934e Mon Sep 17 00:00:00 2001
+From: Arnd Bergmann <arnd@arndb.de>
+Date: Tue, 16 May 2023 18:06:37 +0200
+Subject: arm64: module-plts: inline linux/moduleloader.h
+
+From: Arnd Bergmann <arnd@arndb.de>
+
+commit 60a0aab7463ee69296692d980b96510ccce3934e upstream.
+
+module_frob_arch_sections() is declared in moduleloader.h, but
+that is not included before the definition:
+
+arch/arm64/kernel/module-plts.c:286:5: error: no previous prototype for 'module_frob_arch_sections' [-Werror=missing-prototypes]
+
+Signed-off-by: Arnd Bergmann <arnd@arndb.de>
+Reviewed-by: Kees Cook <keescook@chromium.org>
+Acked-by: Ard Biesheuvel <ardb@kernel.org>
+Link: https://lore.kernel.org/r/20230516160642.523862-11-arnd@kernel.org
+Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/arm64/kernel/module-plts.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/arch/arm64/kernel/module-plts.c
++++ b/arch/arm64/kernel/module-plts.c
+@@ -7,6 +7,7 @@
+ #include <linux/ftrace.h>
+ #include <linux/kernel.h>
+ #include <linux/module.h>
++#include <linux/moduleloader.h>
+ #include <linux/sort.h>
+
+ static struct plt_entry __get_adrp_add_pair(u64 dst, u64 pc,
--- /dev/null
+From f928f8b1a2496e7af95b860f9acf553f20f68f16 Mon Sep 17 00:00:00 2001
+From: James Morse <james.morse@arm.com>
+Date: Tue, 1 Aug 2023 14:54:08 +0000
+Subject: arm64: module: Use module_init_layout_section() to spot init sections
+
+From: James Morse <james.morse@arm.com>
+
+commit f928f8b1a2496e7af95b860f9acf553f20f68f16 upstream.
+
+Today module_frob_arch_sections() spots init sections from their
+'init' prefix, and uses this to keep the init PLTs separate from the rest.
+
+module_emit_plt_entry() uses within_module_init() to determine if a
+location is in the init text or not, but this depends on whether
+core code thought this was an init section.
+
+Naturally the logic is different.
+
+module_init_layout_section() groups the init and exit text together if
+module unloading is disabled, as the exit code will never run. The result
+is kernels with this configuration can't load all their modules because
+there are not enough PLTs for the combined init+exit section.
+
+This results in the following:
+| WARNING: CPU: 2 PID: 51 at arch/arm64/kernel/module-plts.c:99 module_emit_plt_entry+0x184/0x1cc
+| Modules linked in: crct10dif_common
+| CPU: 2 PID: 51 Comm: modprobe Not tainted 6.5.0-rc4-yocto-standard-dirty #15208
+| Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
+| pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
+| pc : module_emit_plt_entry+0x184/0x1cc
+| lr : module_emit_plt_entry+0x94/0x1cc
+| sp : ffffffc0803bba60
+[...]
+| Call trace:
+| module_emit_plt_entry+0x184/0x1cc
+| apply_relocate_add+0x2bc/0x8e4
+| load_module+0xe34/0x1bd4
+| init_module_from_file+0x84/0xc0
+| __arm64_sys_finit_module+0x1b8/0x27c
+| invoke_syscall.constprop.0+0x5c/0x104
+| do_el0_svc+0x58/0x160
+| el0_svc+0x38/0x110
+| el0t_64_sync_handler+0xc0/0xc4
+| el0t_64_sync+0x190/0x194
+
+A previous patch exposed module_init_layout_section(), use that so the
+logic is the same.
+
+Reported-by: Adam Johnston <adam.johnston@arm.com>
+Tested-by: Adam Johnston <adam.johnston@arm.com>
+Fixes: 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()")
+Cc: <stable@vger.kernel.org> # 5.15.x: 60a0aab7463ee69 arm64: module-plts: inline linux/moduleloader.h
+Cc: <stable@vger.kernel.org> # 5.15.x
+Signed-off-by: James Morse <james.morse@arm.com>
+Acked-by: Catalin Marinas <catalin.marinas@arm.com>
+Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/arm64/kernel/module-plts.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/arm64/kernel/module-plts.c
++++ b/arch/arm64/kernel/module-plts.c
+@@ -343,7 +343,7 @@ int module_frob_arch_sections(Elf_Ehdr *
+ if (nents)
+ sort(rels, nents, sizeof(Elf64_Rela), cmp_rela, NULL);
+
+- if (!str_has_prefix(secstrings + dstsec->sh_name, ".init"))
++ if (!module_init_layout_section(secstrings + dstsec->sh_name))
+ core_plts += count_plts(syms, rels, numrels,
+ sechdrs[i].sh_info, dstsec);
+ else
--- /dev/null
+From 2abcc4b5a64a65a2d2287ba0be5c2871c1552416 Mon Sep 17 00:00:00 2001
+From: James Morse <james.morse@arm.com>
+Date: Tue, 1 Aug 2023 14:54:07 +0000
+Subject: module: Expose module_init_layout_section()
+
+From: James Morse <james.morse@arm.com>
+
+commit 2abcc4b5a64a65a2d2287ba0be5c2871c1552416 upstream.
+
+module_init_layout_section() choses whether the core module loader
+considers a section as init or not. This affects the placement of the
+exit section when module unloading is disabled. This code will never run,
+so it can be free()d once the module has been initialised.
+
+arm and arm64 need to count the number of PLTs they need before applying
+relocations based on the section name. The init PLTs are stored separately
+so they can be free()d. arm and arm64 both use within_module_init() to
+decide which list of PLTs to use when applying the relocation.
+
+Because within_module_init()'s behaviour changes when module unloading
+is disabled, both architecture would need to take this into account when
+counting the PLTs.
+
+Today neither architecture does this, meaning when module unloading is
+disabled there are insufficient PLTs in the init section to load some
+modules, resulting in warnings:
+| WARNING: CPU: 2 PID: 51 at arch/arm64/kernel/module-plts.c:99 module_emit_plt_entry+0x184/0x1cc
+| Modules linked in: crct10dif_common
+| CPU: 2 PID: 51 Comm: modprobe Not tainted 6.5.0-rc4-yocto-standard-dirty #15208
+| Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
+| pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
+| pc : module_emit_plt_entry+0x184/0x1cc
+| lr : module_emit_plt_entry+0x94/0x1cc
+| sp : ffffffc0803bba60
+[...]
+| Call trace:
+| module_emit_plt_entry+0x184/0x1cc
+| apply_relocate_add+0x2bc/0x8e4
+| load_module+0xe34/0x1bd4
+| init_module_from_file+0x84/0xc0
+| __arm64_sys_finit_module+0x1b8/0x27c
+| invoke_syscall.constprop.0+0x5c/0x104
+| do_el0_svc+0x58/0x160
+| el0_svc+0x38/0x110
+| el0t_64_sync_handler+0xc0/0xc4
+| el0t_64_sync+0x190/0x194
+
+Instead of duplicating module_init_layout_section()s logic, expose it.
+
+Reported-by: Adam Johnston <adam.johnston@arm.com>
+Fixes: 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()")
+Cc: stable@vger.kernel.org
+Signed-off-by: James Morse <james.morse@arm.com>
+Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/moduleloader.h | 5 +++++
+ kernel/module.c | 2 +-
+ 2 files changed, 6 insertions(+), 1 deletion(-)
+
+--- a/include/linux/moduleloader.h
++++ b/include/linux/moduleloader.h
+@@ -39,6 +39,11 @@ bool module_init_section(const char *nam
+ */
+ bool module_exit_section(const char *name);
+
++/* Describes whether within_module_init() will consider this an init section
++ * or not. This behaviour changes with CONFIG_MODULE_UNLOAD.
++ */
++bool module_init_layout_section(const char *sname);
++
+ /*
+ * Apply the given relocation to the (simplified) ELF. Return -error
+ * or 0.
+--- a/kernel/module.c
++++ b/kernel/module.c
+@@ -2407,7 +2407,7 @@ static long get_offset(struct module *mo
+ return ret;
+ }
+
+-static bool module_init_layout_section(const char *sname)
++bool module_init_layout_section(const char *sname)
+ {
+ #ifndef CONFIG_MODULE_UNLOAD
+ if (module_exit_section(sname))
acpi-thermal-drop-nocrt-parameter.patch
+module-expose-module_init_layout_section.patch
+arm64-module-plts-inline-linux-moduleloader.h.patch
+arm64-module-use-module_init_layout_section-to-spot-init-sections.patch
+arm-module-use-module_init_layout_section-to-spot-init-sections.patch
projects / thirdparty / kernel / stable-queue.git / commitdiff
