From ceca927c86e6f72f72d45487a34368bc9509431d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 29 Aug 2025 12:07:25 -0700 Subject: [PATCH 1/5] arm64: mm: Fix CFI failure due to kpti_ng_pgd_alloc function signature Seen during KPTI initialization: CFI failure at create_kpti_ng_temp_pgd+0x124/0xce8 (target: kpti_ng_pgd_alloc+0x0/0x14; expected type: 0xd61b88b6) The call site is alloc_init_pud() at arch/arm64/mm/mmu.c: pud_phys = pgtable_alloc(TABLE_PUD); alloc_init_pud() has the prototype: static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) where the pgtable_alloc() prototype is declared. The target (kpti_ng_pgd_alloc) is used in arch/arm64/kernel/cpufeature.c: create_kpti_ng_temp_pgd(kpti_ng_temp_pgd, __pa(alloc), KPTI_NG_TEMP_VA, PAGE_SIZE, PAGE_KERNEL, kpti_ng_pgd_alloc, 0); which is an alias for __create_pgd_mapping_locked() with prototype: extern __alias(__create_pgd_mapping_locked) void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags); __create_pgd_mapping_locked() passes the function pointer down: __create_pgd_mapping_locked() -> alloc_init_p4d() -> alloc_init_pud() But the target function (kpti_ng_pgd_alloc) has the wrong signature: static phys_addr_t __init kpti_ng_pgd_alloc(int shift); The "int" should be "enum pgtable_type". To make "enum pgtable_type" available to cpufeature.c, move enum pgtable_type definition from arch/arm64/mm/mmu.c to arch/arm64/include/asm/mmu.h. Adjust kpti_ng_pgd_alloc to use "enum pgtable_type" instead of "int". The function behavior remains identical (parameter is unused). Fixes: c64f46ee1377 ("arm64: mm: use enum to identify pgtable level instead of *_SHIFT") Cc: # 6.16.x Signed-off-by: Kees Cook Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250829190721.it.373-kees@kernel.org Reviewed-by: Ryan Roberts Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/mmu.h | 7 +++++++ arch/arm64/kernel/cpufeature.c | 5 +++-- arch/arm64/mm/mmu.c | 7 ------- 3 files changed, 10 insertions(+), 9 deletions(-) diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h index 6e8aa8e72601..49f1a810df16 100644 --- a/arch/arm64/include/asm/mmu.h +++ b/arch/arm64/include/asm/mmu.h @@ -17,6 +17,13 @@ #include #include +enum pgtable_type { + TABLE_PTE, + TABLE_PMD, + TABLE_PUD, + TABLE_P4D, +}; + typedef struct { atomic64_t id; #ifdef CONFIG_COMPAT diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 9ad065f15f1d..e49d142a281f 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -84,6 +84,7 @@ #include #include #include +#include #include #include #include @@ -1945,11 +1946,11 @@ static bool has_pmuv3(const struct arm64_cpu_capabilities *entry, int scope) extern void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags); + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags); static phys_addr_t __initdata kpti_ng_temp_alloc; -static phys_addr_t __init kpti_ng_pgd_alloc(int shift) +static phys_addr_t __init kpti_ng_pgd_alloc(enum pgtable_type type) { kpti_ng_temp_alloc -= PAGE_SIZE; return kpti_ng_temp_alloc; diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 34e5d78af076..183801520740 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -47,13 +47,6 @@ #define NO_CONT_MAPPINGS BIT(1) #define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */ -enum pgtable_type { - TABLE_PTE, - TABLE_PMD, - TABLE_PUD, - TABLE_P4D, -}; - u64 kimage_voffset __ro_after_init; EXPORT_SYMBOL(kimage_voffset); From d82aa5d3501b25bfb7bc2a24a68ad0a83b2ad10b Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 12 Aug 2025 15:49:27 +0100 Subject: [PATCH 2/5] kselftest/arm64: Don't open code SVE_PT_SIZE() in fp-ptrace In fp-trace when allocating a buffer to write SVE register data we open code the addition of the header size to the VL depeendent register data size, which lead to an underallocation bug when we cut'n'pasted the code for FPSIMD format writes. Use the SVE_PT_SIZE() macro that the kernel UAPI provides for this. Fixes: b84d2b27954f ("kselftest/arm64: Test FPSIMD format data writes via NT_ARM_SVE in fp-ptrace") Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20250812-arm64-fp-trace-macro-v1-1-317cfff986a5@kernel.org Signed-off-by: Catalin Marinas --- tools/testing/selftests/arm64/fp/fp-ptrace.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/arm64/fp/fp-ptrace.c b/tools/testing/selftests/arm64/fp/fp-ptrace.c index 124bc883365e..cdd7a45c045d 100644 --- a/tools/testing/selftests/arm64/fp/fp-ptrace.c +++ b/tools/testing/selftests/arm64/fp/fp-ptrace.c @@ -1187,7 +1187,7 @@ static void sve_write_sve(pid_t child, struct test_config *config) if (!vl) return; - iov.iov_len = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, SVE_PT_REGS_SVE); + iov.iov_len = SVE_PT_SIZE(vq, SVE_PT_REGS_SVE); iov.iov_base = malloc(iov.iov_len); if (!iov.iov_base) { ksft_print_msg("Failed allocating %lu byte SVE write buffer\n", @@ -1234,8 +1234,7 @@ static void sve_write_fpsimd(pid_t child, struct test_config *config) if (!vl) return; - iov.iov_len = SVE_PT_SVE_OFFSET + SVE_PT_SVE_SIZE(vq, - SVE_PT_REGS_FPSIMD); + iov.iov_len = SVE_PT_SIZE(vq, SVE_PT_REGS_FPSIMD); iov.iov_base = malloc(iov.iov_len); if (!iov.iov_base) { ksft_print_msg("Failed allocating %lu byte SVE write buffer\n", From 9a6d3ff10f7f538835cae4799562004ee46922c5 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Thu, 21 Aug 2025 09:56:44 +0200 Subject: [PATCH 3/5] arm64: uapi: Provide correct __BITS_PER_LONG for the compat vDSO MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The generic vDSO library uses the UAPI headers. On arm64 __BITS_PER_LONG is always '64' even when used from the compat vDSO. In that case __GENMASK() does an illegal bitshift, invoking undefined behaviour. Change __BITS_PER_LONG to also work when used from the comapt vDSO. To not confuse real userspace, only do this when building the kernel. Reported-by: John Stultz Closes: https://lore.kernel.org/lkml/CANDhNCqvKOc9JgphQwr0eDyJiyG4oLFS9R8rSFvU0fpurrJFDg@mail.gmail.com/ Fixes: cd3557a7618b ("vdso/gettimeofday: Add support for auxiliary clocks") Signed-off-by: Thomas Weißschuh Acked-by: Arnd Bergmann Tested-by: John Stultz Link: https://lore.kernel.org/r/20250821-vdso-arm64-compat-bitsperlong-v1-1-700bcabe7732@linutronix.de Signed-off-by: Catalin Marinas --- arch/arm64/include/uapi/asm/bitsperlong.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm64/include/uapi/asm/bitsperlong.h b/arch/arm64/include/uapi/asm/bitsperlong.h index 485d60bee26c..d59730975f30 100644 --- a/arch/arm64/include/uapi/asm/bitsperlong.h +++ b/arch/arm64/include/uapi/asm/bitsperlong.h @@ -17,7 +17,12 @@ #ifndef __ASM_BITSPERLONG_H #define __ASM_BITSPERLONG_H +#if defined(__KERNEL__) && !defined(__aarch64__) +/* Used by the compat vDSO */ +#define __BITS_PER_LONG 32 +#else #define __BITS_PER_LONG 64 +#endif #include From f3ef7110924b897f4b79db9f7ac75d319ec09c4a Mon Sep 17 00:00:00 2001 From: Miaoqian Lin Date: Thu, 28 Aug 2025 19:22:43 +0800 Subject: [PATCH 4/5] ACPI/IORT: Fix memory leak in iort_rmr_alloc_sids() If krealloc_array() fails in iort_rmr_alloc_sids(), the function returns NULL but does not free the original 'sids' allocation. This results in a memory leak since the caller overwrites the original pointer with the NULL return value. Fixes: 491cf4a6735a ("ACPI/IORT: Add support to retrieve IORT RMR reserved regions") Cc: # 6.0.x Signed-off-by: Miaoqian Lin Reviewed-by: Hanjun Guo Link: https://lore.kernel.org/r/20250828112243.61460-1-linmq006@gmail.com Signed-off-by: Catalin Marinas --- drivers/acpi/arm64/iort.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 98759d6199d3..65f0f56ad753 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -937,8 +937,10 @@ static u32 *iort_rmr_alloc_sids(u32 *sids, u32 count, u32 id_start, new_sids = krealloc_array(sids, count + new_count, sizeof(*new_sids), GFP_KERNEL); - if (!new_sids) + if (!new_sids) { + kfree(sids); return NULL; + } for (i = count; i < total_count; i++) new_sids[i] = id_start++; From a7ed7b9d0ebb038db9963d574da0311cab0b666a Mon Sep 17 00:00:00 2001 From: panfan Date: Thu, 4 Sep 2025 20:22:36 -0700 Subject: [PATCH 5/5] arm64: ftrace: fix unreachable PLT for ftrace_caller in init_module with CONFIG_DYNAMIC_FTRACE On arm64, it has been possible for a module's sections to be placed more than 128M away from each other since commit: commit 3e35d303ab7d ("arm64: module: rework module VA range selection") Due to this, an ftrace callsite in a module's .init.text section can be out of branch range for the module's ftrace PLT entry (in the module's .text section). Any attempt to enable tracing of that callsite will result in a BRK being patched into the callsite, resulting in a fatal exception when the callsite is later executed. Fix this by adding an additional trampoline for .init.text, which will be within range. No additional trampolines are necessary due to the way a given module's executable sections are packed together. Any executable section beginning with ".init" will be placed in MOD_INIT_TEXT, and any other executable section, including those beginning with ".exit", will be placed in MOD_TEXT. Fixes: 3e35d303ab7d ("arm64: module: rework module VA range selection") Cc: # 6.5.x Signed-off-by: panfan Acked-by: Mark Rutland Link: https://lore.kernel.org/r/20250905032236.3220885-1-panfan@qti.qualcomm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/module.h | 1 + arch/arm64/include/asm/module.lds.h | 1 + arch/arm64/kernel/ftrace.c | 13 ++++++++++--- arch/arm64/kernel/module-plts.c | 12 +++++++++++- arch/arm64/kernel/module.c | 11 +++++++++++ 5 files changed, 34 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/module.h b/arch/arm64/include/asm/module.h index 79550b22ba19..fb9b88eebeb1 100644 --- a/arch/arm64/include/asm/module.h +++ b/arch/arm64/include/asm/module.h @@ -19,6 +19,7 @@ struct mod_arch_specific { /* for CONFIG_DYNAMIC_FTRACE */ struct plt_entry *ftrace_trampolines; + struct plt_entry *init_ftrace_trampolines; }; u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs, diff --git a/arch/arm64/include/asm/module.lds.h b/arch/arm64/include/asm/module.lds.h index b9ae8349e35d..fb944b46846d 100644 --- a/arch/arm64/include/asm/module.lds.h +++ b/arch/arm64/include/asm/module.lds.h @@ -2,6 +2,7 @@ SECTIONS { .plt 0 : { BYTE(0) } .init.plt 0 : { BYTE(0) } .text.ftrace_trampoline 0 : { BYTE(0) } + .init.text.ftrace_trampoline 0 : { BYTE(0) } #ifdef CONFIG_KASAN_SW_TAGS /* diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 5a890714ee2e..5adad37ab4fa 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -258,10 +258,17 @@ int ftrace_update_ftrace_func(ftrace_func_t func) return ftrace_modify_code(pc, 0, new, false); } -static struct plt_entry *get_ftrace_plt(struct module *mod) +static struct plt_entry *get_ftrace_plt(struct module *mod, unsigned long addr) { #ifdef CONFIG_MODULES - struct plt_entry *plt = mod->arch.ftrace_trampolines; + struct plt_entry *plt = NULL; + + if (within_module_mem_type(addr, mod, MOD_INIT_TEXT)) + plt = mod->arch.init_ftrace_trampolines; + else if (within_module_mem_type(addr, mod, MOD_TEXT)) + plt = mod->arch.ftrace_trampolines; + else + return NULL; return &plt[FTRACE_PLT_IDX]; #else @@ -332,7 +339,7 @@ static bool ftrace_find_callable_addr(struct dyn_ftrace *rec, if (WARN_ON(!mod)) return false; - plt = get_ftrace_plt(mod); + plt = get_ftrace_plt(mod, pc); if (!plt) { pr_err("ftrace: no module PLT for %ps\n", (void *)*addr); return false; diff --git a/arch/arm64/kernel/module-plts.c b/arch/arm64/kernel/module-plts.c index bde32979c06a..7afd370da9f4 100644 --- a/arch/arm64/kernel/module-plts.c +++ b/arch/arm64/kernel/module-plts.c @@ -283,7 +283,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, unsigned long core_plts = 0; unsigned long init_plts = 0; Elf64_Sym *syms = NULL; - Elf_Shdr *pltsec, *tramp = NULL; + Elf_Shdr *pltsec, *tramp = NULL, *init_tramp = NULL; int i; /* @@ -298,6 +298,9 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, else if (!strcmp(secstrings + sechdrs[i].sh_name, ".text.ftrace_trampoline")) tramp = sechdrs + i; + else if (!strcmp(secstrings + sechdrs[i].sh_name, + ".init.text.ftrace_trampoline")) + init_tramp = sechdrs + i; else if (sechdrs[i].sh_type == SHT_SYMTAB) syms = (Elf64_Sym *)sechdrs[i].sh_addr; } @@ -363,5 +366,12 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, tramp->sh_size = NR_FTRACE_PLTS * sizeof(struct plt_entry); } + if (init_tramp) { + init_tramp->sh_type = SHT_NOBITS; + init_tramp->sh_flags = SHF_EXECINSTR | SHF_ALLOC; + init_tramp->sh_addralign = __alignof__(struct plt_entry); + init_tramp->sh_size = NR_FTRACE_PLTS * sizeof(struct plt_entry); + } + return 0; } diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c index 40148d2725ce..d6d443c4a01a 100644 --- a/arch/arm64/kernel/module.c +++ b/arch/arm64/kernel/module.c @@ -466,6 +466,17 @@ static int module_init_ftrace_plt(const Elf_Ehdr *hdr, __init_plt(&plts[FTRACE_PLT_IDX], FTRACE_ADDR); mod->arch.ftrace_trampolines = plts; + + s = find_section(hdr, sechdrs, ".init.text.ftrace_trampoline"); + if (!s) + return -ENOEXEC; + + plts = (void *)s->sh_addr; + + __init_plt(&plts[FTRACE_PLT_IDX], FTRACE_ADDR); + + mod->arch.init_ftrace_trampolines = plts; + #endif return 0; }