diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index be439e246d91..dbe64f27280e 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -706,7 +706,7 @@ __copy_from_user_overflow(int size, unsigned long count) #endif -static inline unsigned long __must_check +static __always_inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n) { int sz = __compiletime_object_size(to); @@ -742,7 +742,7 @@ copy_from_user(void *to, const void __user *from, unsigned long n) return n; } -static inline unsigned long __must_check +static __always_inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n) { int sz = __compiletime_object_size(from); diff --git a/block/blk-core.c b/block/blk-core.c index b20ada4ad68e..32e5bd63f6ae 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -3560,6 +3560,7 @@ blk_zero_latency_hist(struct io_latency_state *s) s->latency_reads_elems = 0; s->latency_writes_elems = 0; } +EXPORT_SYMBOL(blk_zero_latency_hist); ssize_t blk_latency_hist_show(struct io_latency_state *s, char *buf) @@ -3621,3 +3622,4 @@ blk_latency_hist_show(struct io_latency_state *s, char *buf) } return bytes_written; } +EXPORT_SYMBOL(blk_latency_hist_show); diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index ec791e169f8f..936960202cf4 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1251,6 +1251,7 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, /* Ignore report if ErrorRollOver */ if (!(field->flags & HID_MAIN_ITEM_VARIABLE) && value[n] >= min && value[n] <= max && + value[n] - min < field->maxusage && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) goto exit; } @@ -1263,11 +1264,13 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, } if (field->value[n] >= min && field->value[n] <= max + && field->value[n] - min < field->maxusage && field->usage[field->value[n] - min].hid && search(value, field->value[n], count)) hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); if (value[n] >= min && value[n] <= max + && value[n] - min < field->maxusage && field->usage[value[n] - min].hid && search(field->value, value[n], count)) hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 588461bb2dd4..40a0fe0a4e05 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -431,6 +431,40 @@ static int pstore_write_compat(enum pstore_type_id type, size, psi); } +static int pstore_write_buf_user_compat(enum pstore_type_id type, + enum kmsg_dump_reason reason, + u64 *id, unsigned int part, + const char __user *buf, + bool compressed, size_t size, + struct pstore_info *psi) +{ + unsigned long flags = 0; + size_t i, bufsize = size; + long ret = 0; + + if (unlikely(!access_ok(VERIFY_READ, buf, size))) + return -EFAULT; + if (bufsize > psinfo->bufsize) + bufsize = psinfo->bufsize; + spin_lock_irqsave(&psinfo->buf_lock, flags); + for (i = 0; i < size; ) { + size_t c = min(size - i, bufsize); + + ret = __copy_from_user(psinfo->buf, buf + i, c); + if (unlikely(ret != 0)) { + ret = -EFAULT; + break; + } + ret = psi->write_buf(type, reason, id, part, psinfo->buf, + compressed, c, psi); + if (unlikely(ret < 0)) + break; + i += c; + } + spin_unlock_irqrestore(&psinfo->buf_lock, flags); + return unlikely(ret < 0) ? ret : size; +} + /* * platform specific persistent storage driver registers with * us here. If pstore is already mounted, call the platform @@ -453,6 +487,8 @@ int pstore_register(struct pstore_info *psi) if (!psi->write) psi->write = pstore_write_compat; + if (!psi->write_buf_user) + psi->write_buf_user = pstore_write_buf_user_compat; psinfo = psi; mutex_init(&psinfo->read_mutex); spin_unlock(&pstore_lock); diff --git a/fs/pstore/pmsg.c b/fs/pstore/pmsg.c index 7de20cd3797f..78f6176c020f 100644 --- a/fs/pstore/pmsg.c +++ b/fs/pstore/pmsg.c @@ -19,48 +19,25 @@ #include "internal.h" static DEFINE_MUTEX(pmsg_lock); -#define PMSG_MAX_BOUNCE_BUFFER_SIZE (2*PAGE_SIZE) static ssize_t write_pmsg(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - size_t i, buffer_size; - char *buffer; + u64 id; + int ret; if (!count) return 0; + /* check outside lock, page in any data. write_buf_user also checks */ if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; - buffer_size = count; - if (buffer_size > PMSG_MAX_BOUNCE_BUFFER_SIZE) - buffer_size = PMSG_MAX_BOUNCE_BUFFER_SIZE; - buffer = vmalloc(buffer_size); - if (!buffer) - return -ENOMEM; - mutex_lock(&pmsg_lock); - for (i = 0; i < count; ) { - size_t c = min(count - i, buffer_size); - u64 id; - long ret; - - ret = __copy_from_user(buffer, buf + i, c); - if (unlikely(ret != 0)) { - mutex_unlock(&pmsg_lock); - vfree(buffer); - return -EFAULT; - } - psinfo->write_buf(PSTORE_TYPE_PMSG, 0, &id, 0, buffer, 0, c, - psinfo); - - i += c; - } - + ret = psinfo->write_buf_user(PSTORE_TYPE_PMSG, 0, &id, 0, buf, 0, count, + psinfo); mutex_unlock(&pmsg_lock); - vfree(buffer); - return count; + return ret ? ret : count; } static const struct file_operations pmsg_fops = { diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 414041342a99..5b10c2b4146c 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -331,6 +331,24 @@ static int notrace ramoops_pstore_write_buf(enum pstore_type_id type, return 0; } +static int notrace ramoops_pstore_write_buf_user(enum pstore_type_id type, + enum kmsg_dump_reason reason, + u64 *id, unsigned int part, + const char __user *buf, + bool compressed, size_t size, + struct pstore_info *psi) +{ + if (type == PSTORE_TYPE_PMSG) { + struct ramoops_context *cxt = psi->data; + + if (!cxt->mprz) + return -ENOMEM; + return persistent_ram_write_user(cxt->mprz, buf, size); + } + + return -EINVAL; +} + static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { @@ -369,6 +387,7 @@ static struct ramoops_context oops_cxt = { .open = ramoops_pstore_open, .read = ramoops_pstore_read, .write_buf = ramoops_pstore_write_buf, + .write_buf_user = ramoops_pstore_write_buf_user, .erase = ramoops_pstore_erase, }, }; diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 76c3f80efdfa..aa9afe573155 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -17,15 +17,16 @@ #include #include #include -#include #include #include +#include #include #include +#include #include #include +#include #include -#include #include struct persistent_ram_buffer { @@ -303,6 +304,16 @@ static void notrace persistent_ram_update(struct persistent_ram_zone *prz, persistent_ram_update_ecc(prz, start, count); } +static int notrace persistent_ram_update_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int start, unsigned int count) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + int ret = unlikely(__copy_from_user(buffer->data + start, s, count)) ? + -EFAULT : 0; + persistent_ram_update_ecc(prz, start, count); + return ret; +} + void persistent_ram_save_old(struct persistent_ram_zone *prz) { struct persistent_ram_buffer *buffer = prz->buffer; @@ -356,6 +367,38 @@ int notrace persistent_ram_write(struct persistent_ram_zone *prz, return count; } +int notrace persistent_ram_write_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int count) +{ + int rem, ret = 0, c = count; + size_t start; + + if (unlikely(!access_ok(VERIFY_READ, s, count))) + return -EFAULT; + if (unlikely(c > prz->buffer_size)) { + s += c - prz->buffer_size; + c = prz->buffer_size; + } + + buffer_size_add(prz, c); + + start = buffer_start_add(prz, c); + + rem = prz->buffer_size - start; + if (unlikely(rem < c)) { + ret = persistent_ram_update_user(prz, s, start, rem); + s += rem; + c -= rem; + start = 0; + } + if (likely(!ret)) + ret = persistent_ram_update_user(prz, s, start, c); + + persistent_ram_update_header_ecc(prz); + + return unlikely(ret) ? ret : count; +} + size_t persistent_ram_old_size(struct persistent_ram_zone *prz) { return prz->old_log_size; diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index e4862f7cdede..97b2b0b1f99d 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -380,8 +380,10 @@ struct mmc_host { } embedded_sdio_data; #endif +#ifdef CONFIG_BLOCK int latency_hist_enabled; struct io_latency_state io_lat_s; +#endif unsigned long private[0] ____cacheline_aligned; }; diff --git a/include/linux/pstore.h b/include/linux/pstore.h index 831479f8df8f..5cae2c6c90ad 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -22,12 +22,13 @@ #ifndef _LINUX_PSTORE_H #define _LINUX_PSTORE_H -#include +#include +#include #include #include -#include #include -#include +#include +#include /* types */ enum pstore_type_id { @@ -67,6 +68,10 @@ struct pstore_info { enum kmsg_dump_reason reason, u64 *id, unsigned int part, const char *buf, bool compressed, size_t size, struct pstore_info *psi); + int (*write_buf_user)(enum pstore_type_id type, + enum kmsg_dump_reason reason, u64 *id, + unsigned int part, const char __user *buf, + bool compressed, size_t size, struct pstore_info *psi); int (*erase)(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi); diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h index 712757f320a4..45ac5a0d29ee 100644 --- a/include/linux/pstore_ram.h +++ b/include/linux/pstore_ram.h @@ -17,11 +17,12 @@ #ifndef __LINUX_PSTORE_RAM_H__ #define __LINUX_PSTORE_RAM_H__ +#include #include +#include #include #include #include -#include struct persistent_ram_buffer; struct rs_control; @@ -59,7 +60,9 @@ void persistent_ram_free(struct persistent_ram_zone *prz); void persistent_ram_zap(struct persistent_ram_zone *prz); int persistent_ram_write(struct persistent_ram_zone *prz, const void *s, - unsigned int count); + unsigned int count); +int persistent_ram_write_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int count); void persistent_ram_save_old(struct persistent_ram_zone *prz); size_t persistent_ram_old_size(struct persistent_ram_zone *prz); diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h index 0ae29ff9ccfd..4cf89517783a 100644 --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -158,10 +158,11 @@ static inline int arch_within_stack_frames(const void * const stack, extern void __check_object_size(const void *ptr, unsigned long n, bool to_user); -static inline void check_object_size(const void *ptr, unsigned long n, - bool to_user) +static __always_inline void check_object_size(const void *ptr, unsigned long n, + bool to_user) { - __check_object_size(ptr, n, to_user); + if (!__builtin_constant_p(n)) + __check_object_size(ptr, n, to_user); } #else static inline void check_object_size(const void *ptr, unsigned long n, diff --git a/mm/usercopy.c b/mm/usercopy.c index f78015e8b1e5..b34996a3860b 100644 --- a/mm/usercopy.c +++ b/mm/usercopy.c @@ -135,30 +135,15 @@ static inline const char *check_bogus_address(const void *ptr, unsigned long n) return NULL; } -static inline const char *check_heap_object(const void *ptr, unsigned long n, - bool to_user) +/* Checks for allocs that are marked in some way as spanning multiple pages. */ +static inline const char *check_page_span(const void *ptr, unsigned long n, + struct page *page, bool to_user) { - struct page *page, *endpage; +#ifdef CONFIG_HARDENED_USERCOPY_PAGESPAN const void *end = ptr + n - 1; + struct page *endpage; bool is_reserved, is_cma; - /* - * Some architectures (arm64) return true for virt_addr_valid() on - * vmalloced addresses. Work around this by checking for vmalloc - * first. - */ - if (is_vmalloc_addr(ptr)) - return NULL; - - if (!virt_addr_valid(ptr)) - return NULL; - - page = virt_to_head_page(ptr); - - /* Check slab allocator for flags and size. */ - if (PageSlab(page)) - return __check_heap_object(ptr, n, page); - /* * Sometimes the kernel data regions are not marked Reserved (see * check below). And sometimes [_sdata,_edata) does not cover @@ -187,7 +172,7 @@ static inline const char *check_heap_object(const void *ptr, unsigned long n, ((unsigned long)end & (unsigned long)PAGE_MASK))) return NULL; - /* Allow if start and end are inside the same compound page. */ + /* Allow if fully inside the same compound (__GFP_COMP) page. */ endpage = virt_to_head_page(end); if (likely(endpage == page)) return NULL; @@ -200,20 +185,44 @@ static inline const char *check_heap_object(const void *ptr, unsigned long n, is_reserved = PageReserved(page); is_cma = is_migrate_cma_page(page); if (!is_reserved && !is_cma) - goto reject; + return ""; for (ptr += PAGE_SIZE; ptr <= end; ptr += PAGE_SIZE) { page = virt_to_head_page(ptr); if (is_reserved && !PageReserved(page)) - goto reject; + return ""; if (is_cma && !is_migrate_cma_page(page)) - goto reject; + return ""; } +#endif return NULL; +} -reject: - return ""; +static inline const char *check_heap_object(const void *ptr, unsigned long n, + bool to_user) +{ + struct page *page; + + /* + * Some architectures (arm64) return true for virt_addr_valid() on + * vmalloced addresses. Work around this by checking for vmalloc + * first. + */ + if (is_vmalloc_addr(ptr)) + return NULL; + + if (!virt_addr_valid(ptr)) + return NULL; + + page = virt_to_head_page(ptr); + + /* Check slab allocator for flags and size. */ + if (PageSlab(page)) + return __check_heap_object(ptr, n, page); + + /* Verify object does not incorrectly span multiple pages. */ + return check_page_span(ptr, n, page, to_user); } /* diff --git a/security/Kconfig b/security/Kconfig index 2b42c225de28..3aa60791f84d 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -156,6 +156,17 @@ config HARDENED_USERCOPY or are part of the kernel text. This kills entire classes of heap overflow exploits and similar kernel memory exposures. +config HARDENED_USERCOPY_PAGESPAN + bool "Refuse to copy allocations that span multiple pages" + depends on HARDENED_USERCOPY + depends on !COMPILE_TEST + help + When a multi-page allocation is done without __GFP_COMP, + hardened usercopy will reject attempts to copy it. There are, + however, several cases of this in the kernel that have not all + been removed. This config is intended to be used only while + trying to find such users. + source security/selinux/Kconfig source security/smack/Kconfig source security/tomoyo/Kconfig