From c307459b9d1fcb8bbf3ea5a4162979532322ef77 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:13 -0700 Subject: fs/kernel_read_file: Remove FIRMWARE_PREALLOC_BUFFER enum FIRMWARE_PREALLOC_BUFFER is a "how", not a "what", and confuses the LSMs that are interested in filtering between types of things. The "how" should be an internal detail made uninteresting to the LSMs. Fixes: a098ecd2fa7d ("firmware: support loading into a pre-allocated buffer") Fixes: fd90bc559bfb ("ima: based on policy verify firmware signatures (pre-allocated buffer)") Fixes: 4f0496d8ffa3 ("ima: based on policy warn about loading firmware (pre-allocated buffer)") Signed-off-by: Kees Cook Reviewed-by: Mimi Zohar Reviewed-by: Luis Chamberlain Acked-by: Scott Branden Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201002173828.2099543-2-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/main.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 63b9714a0154..b0ec2721f55d 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -470,14 +470,12 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, int i, len; int rc = -ENOENT; char *path; - enum kernel_read_file_id id = READING_FIRMWARE; size_t msize = INT_MAX; void *buffer = NULL; /* Already populated data member means we're loading into a buffer */ if (!decompress && fw_priv->data) { buffer = fw_priv->data; - id = READING_FIRMWARE_PREALLOC_BUFFER; msize = fw_priv->allocated_size; } @@ -501,7 +499,8 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, /* load firmware files from the mount namespace of init */ rc = kernel_read_file_from_path_initns(path, &buffer, - &size, msize, id); + &size, msize, + READING_FIRMWARE); if (rc) { if (rc != -ENOENT) dev_warn(device, "loading %s failed with error %d\n", -- cgit v1.2.3 From 06e67b849ab910a49a629445f43edb074153d0eb Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:14 -0700 Subject: fs/kernel_read_file: Remove FIRMWARE_EFI_EMBEDDED enum The "FIRMWARE_EFI_EMBEDDED" enum is a "where", not a "what". It should not be distinguished separately from just "FIRMWARE", as this confuses the LSMs about what is being loaded. Additionally, there was no actual validation of the firmware contents happening. Fixes: e4c2c0ff00ec ("firmware: Add new platform fallback mechanism and firmware_request_platform()") Signed-off-by: Kees Cook Reviewed-by: Luis Chamberlain Acked-by: Scott Branden Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201002173828.2099543-3-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback_platform.c | 2 +- include/linux/fs.h | 3 +-- 2 files changed, 2 insertions(+), 3 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c index 685edb7dd05a..6958ab1a8059 100644 --- a/drivers/base/firmware_loader/fallback_platform.c +++ b/drivers/base/firmware_loader/fallback_platform.c @@ -17,7 +17,7 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) if (!(opt_flags & FW_OPT_FALLBACK_PLATFORM)) return -ENOENT; - rc = security_kernel_load_data(LOADING_FIRMWARE_EFI_EMBEDDED); + rc = security_kernel_load_data(LOADING_FIRMWARE); if (rc) return rc; diff --git a/include/linux/fs.h b/include/linux/fs.h index 7336e22d0c5d..3fb7af12d033 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2858,11 +2858,10 @@ static inline void i_readcount_inc(struct inode *inode) #endif extern int do_pipe_flags(int *, int); -/* This is a list of *what* is being read, not *how*. */ +/* This is a list of *what* is being read, not *how* nor *where*. */ #define __kernel_read_file_id(id) \ id(UNKNOWN, unknown) \ id(FIRMWARE, firmware) \ - id(FIRMWARE_EFI_EMBEDDED, firmware) \ id(MODULE, kernel-module) \ id(KEXEC_IMAGE, kexec-image) \ id(KEXEC_INITRAMFS, kexec-initramfs) \ -- cgit v1.2.3 From b89999d004931ab2e5123611ace7dab77328f8d6 Mon Sep 17 00:00:00 2001 From: Scott Branden Date: Fri, 2 Oct 2020 10:38:15 -0700 Subject: fs/kernel_read_file: Split into separate include file Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h include file. That header gets pulled in just about everywhere and doesn't really need functions not related to the general fs interface. Suggested-by: Christoph Hellwig Signed-off-by: Scott Branden Signed-off-by: Kees Cook Reviewed-by: Christoph Hellwig Reviewed-by: Mimi Zohar Reviewed-by: Luis Chamberlain Acked-by: Greg Kroah-Hartman Acked-by: James Morris Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/main.c | 1 + fs/exec.c | 1 + include/linux/fs.h | 38 --------------------------- include/linux/ima.h | 1 + include/linux/kernel_read_file.h | 51 +++++++++++++++++++++++++++++++++++++ include/linux/security.h | 1 + kernel/kexec_file.c | 1 + kernel/module.c | 1 + security/integrity/digsig.c | 1 + security/integrity/ima/ima_fs.c | 1 + security/integrity/ima/ima_main.c | 1 + security/integrity/ima/ima_policy.c | 1 + security/loadpin/loadpin.c | 1 + security/security.c | 1 + security/selinux/hooks.c | 1 + 15 files changed, 64 insertions(+), 38 deletions(-) create mode 100644 include/linux/kernel_read_file.h (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index b0ec2721f55d..8c6ea389afcf 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -12,6 +12,7 @@ #include #include +#include #include #include #include diff --git a/fs/exec.c b/fs/exec.c index 9233cd50dc4c..c454af329413 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -23,6 +23,7 @@ * formats. */ +#include #include #include #include diff --git a/include/linux/fs.h b/include/linux/fs.h index 3fb7af12d033..0885d53afb11 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2858,44 +2858,6 @@ static inline void i_readcount_inc(struct inode *inode) #endif extern int do_pipe_flags(int *, int); -/* This is a list of *what* is being read, not *how* nor *where*. */ -#define __kernel_read_file_id(id) \ - id(UNKNOWN, unknown) \ - id(FIRMWARE, firmware) \ - id(MODULE, kernel-module) \ - id(KEXEC_IMAGE, kexec-image) \ - id(KEXEC_INITRAMFS, kexec-initramfs) \ - id(POLICY, security-policy) \ - id(X509_CERTIFICATE, x509-certificate) \ - id(MAX_ID, ) - -#define __fid_enumify(ENUM, dummy) READING_ ## ENUM, -#define __fid_stringify(dummy, str) #str, - -enum kernel_read_file_id { - __kernel_read_file_id(__fid_enumify) -}; - -static const char * const kernel_read_file_str[] = { - __kernel_read_file_id(__fid_stringify) -}; - -static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) -{ - if ((unsigned)id >= READING_MAX_ID) - return kernel_read_file_str[READING_UNKNOWN]; - - return kernel_read_file_str[id]; -} - -extern int kernel_read_file(struct file *, void **, loff_t *, loff_t, - enum kernel_read_file_id); -extern int kernel_read_file_from_path(const char *, void **, loff_t *, loff_t, - enum kernel_read_file_id); -extern int kernel_read_file_from_path_initns(const char *, void **, loff_t *, loff_t, - enum kernel_read_file_id); -extern int kernel_read_file_from_fd(int, void **, loff_t *, loff_t, - enum kernel_read_file_id); extern ssize_t kernel_read(struct file *, void *, size_t, loff_t *); ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos); extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *); diff --git a/include/linux/ima.h b/include/linux/ima.h index d15100de6cdd..64804f78408b 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -7,6 +7,7 @@ #ifndef _LINUX_IMA_H #define _LINUX_IMA_H +#include #include #include #include diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h new file mode 100644 index 000000000000..78cf3d7dc835 --- /dev/null +++ b/include/linux/kernel_read_file.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_KERNEL_READ_FILE_H +#define _LINUX_KERNEL_READ_FILE_H + +#include +#include + +/* This is a list of *what* is being read, not *how* nor *where*. */ +#define __kernel_read_file_id(id) \ + id(UNKNOWN, unknown) \ + id(FIRMWARE, firmware) \ + id(MODULE, kernel-module) \ + id(KEXEC_IMAGE, kexec-image) \ + id(KEXEC_INITRAMFS, kexec-initramfs) \ + id(POLICY, security-policy) \ + id(X509_CERTIFICATE, x509-certificate) \ + id(MAX_ID, ) + +#define __fid_enumify(ENUM, dummy) READING_ ## ENUM, +#define __fid_stringify(dummy, str) #str, + +enum kernel_read_file_id { + __kernel_read_file_id(__fid_enumify) +}; + +static const char * const kernel_read_file_str[] = { + __kernel_read_file_id(__fid_stringify) +}; + +static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) +{ + if ((unsigned int)id >= READING_MAX_ID) + return kernel_read_file_str[READING_UNKNOWN]; + + return kernel_read_file_str[id]; +} + +int kernel_read_file(struct file *file, + void **buf, loff_t *size, loff_t max_size, + enum kernel_read_file_id id); +int kernel_read_file_from_path(const char *path, + void **buf, loff_t *size, loff_t max_size, + enum kernel_read_file_id id); +int kernel_read_file_from_path_initns(const char *path, + void **buf, loff_t *size, loff_t max_size, + enum kernel_read_file_id id); +int kernel_read_file_from_fd(int fd, + void **buf, loff_t *size, loff_t max_size, + enum kernel_read_file_id id); + +#endif /* _LINUX_KERNEL_READ_FILE_H */ diff --git a/include/linux/security.h b/include/linux/security.h index 0a0a03b36a3b..42df0d9b4c37 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -23,6 +23,7 @@ #ifndef __LINUX_SECURITY_H #define __LINUX_SECURITY_H +#include #include #include #include diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index ca40bef75a61..1cc82557f4c1 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include "kexec_internal.h" diff --git a/kernel/module.c b/kernel/module.c index b2808acac46b..4218abd272ee 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index ac02b7632353..f8869be45d8f 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 15a44c5022f7..e13ffece3726 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -13,6 +13,7 @@ */ #include +#include #include #include #include diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 2f187784c5bc..5f89970c5ab7 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index b4de33074b37..3b0b43e18ecf 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -9,6 +9,7 @@ #include #include +#include #include #include #include diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c index 670a1aebb8a1..163c48216d13 100644 --- a/security/loadpin/loadpin.c +++ b/security/loadpin/loadpin.c @@ -11,6 +11,7 @@ #include #include +#include #include #include #include diff --git a/security/security.c b/security/security.c index 70a7ad357bc6..19d3150f68f4 100644 --- a/security/security.c +++ b/security/security.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index a340986aa92e..96f5f8b3b9f0 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include -- cgit v1.2.3 From f7a4f689bca6072492626938aad6dd2f32c5bf97 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:17 -0700 Subject: fs/kernel_read_file: Remove redundant size argument In preparation for refactoring kernel_read_file*(), remove the redundant "size" argument which is not needed: it can be included in the return code, with callers adjusted. (VFS reads already cannot be larger than INT_MAX.) Signed-off-by: Kees Cook Reviewed-by: Mimi Zohar Reviewed-by: Luis Chamberlain Reviewed-by: James Morris Acked-by: Scott Branden Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/main.c | 10 ++++++---- fs/kernel_read_file.c | 20 +++++++++----------- include/linux/kernel_read_file.h | 8 ++++---- kernel/kexec_file.c | 14 +++++++------- kernel/module.c | 7 +++---- security/integrity/digsig.c | 5 +++-- security/integrity/ima/ima_fs.c | 6 ++++-- 7 files changed, 36 insertions(+), 34 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 8c6ea389afcf..6df1bdcfeb9d 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -467,7 +467,7 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, size_t in_size, const void *in_buffer)) { - loff_t size; + size_t size; int i, len; int rc = -ENOENT; char *path; @@ -499,10 +499,9 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, fw_priv->size = 0; /* load firmware files from the mount namespace of init */ - rc = kernel_read_file_from_path_initns(path, &buffer, - &size, msize, + rc = kernel_read_file_from_path_initns(path, &buffer, msize, READING_FIRMWARE); - if (rc) { + if (rc < 0) { if (rc != -ENOENT) dev_warn(device, "loading %s failed with error %d\n", path, rc); @@ -511,6 +510,9 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, path); continue; } + size = rc; + rc = 0; + dev_dbg(device, "Loading firmware from %s\n", path); if (decompress) { dev_dbg(device, "f/w decompressing %s\n", diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c index 54d972d4befc..dc28a8def597 100644 --- a/fs/kernel_read_file.c +++ b/fs/kernel_read_file.c @@ -5,7 +5,7 @@ #include #include -int kernel_read_file(struct file *file, void **buf, loff_t *size, +int kernel_read_file(struct file *file, void **buf, loff_t max_size, enum kernel_read_file_id id) { loff_t i_size, pos; @@ -29,7 +29,7 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, ret = -EINVAL; goto out; } - if (i_size > SIZE_MAX || (max_size > 0 && i_size > max_size)) { + if (i_size > INT_MAX || (max_size > 0 && i_size > max_size)) { ret = -EFBIG; goto out; } @@ -59,8 +59,6 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, } ret = security_kernel_post_read_file(file, *buf, i_size, id); - if (!ret) - *size = pos; out_free: if (ret < 0) { @@ -72,11 +70,11 @@ out_free: out: allow_write_access(file); - return ret; + return ret == 0 ? pos : ret; } EXPORT_SYMBOL_GPL(kernel_read_file); -int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, +int kernel_read_file_from_path(const char *path, void **buf, loff_t max_size, enum kernel_read_file_id id) { struct file *file; @@ -89,14 +87,14 @@ int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, size, max_size, id); + ret = kernel_read_file(file, buf, max_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path); int kernel_read_file_from_path_initns(const char *path, void **buf, - loff_t *size, loff_t max_size, + loff_t max_size, enum kernel_read_file_id id) { struct file *file; @@ -115,13 +113,13 @@ int kernel_read_file_from_path_initns(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, size, max_size, id); + ret = kernel_read_file(file, buf, max_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path_initns); -int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, +int kernel_read_file_from_fd(int fd, void **buf, loff_t max_size, enum kernel_read_file_id id) { struct fd f = fdget(fd); @@ -130,7 +128,7 @@ int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, if (!f.file) goto out; - ret = kernel_read_file(f.file, buf, size, max_size, id); + ret = kernel_read_file(f.file, buf, max_size, id); out: fdput(f); return ret; diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h index 78cf3d7dc835..0ca0bdbed1bd 100644 --- a/include/linux/kernel_read_file.h +++ b/include/linux/kernel_read_file.h @@ -36,16 +36,16 @@ static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) } int kernel_read_file(struct file *file, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); int kernel_read_file_from_path(const char *path, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); int kernel_read_file_from_path_initns(const char *path, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); int kernel_read_file_from_fd(int fd, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); #endif /* _LINUX_KERNEL_READ_FILE_H */ diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 1cc82557f4c1..b20cfde8a01d 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -220,13 +220,12 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, { int ret; void *ldata; - loff_t size; ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, - &size, INT_MAX, READING_KEXEC_IMAGE); - if (ret) + INT_MAX, READING_KEXEC_IMAGE); + if (ret < 0) return ret; - image->kernel_buf_len = size; + image->kernel_buf_len = ret; /* Call arch image probe handlers */ ret = arch_kexec_kernel_image_probe(image, image->kernel_buf, @@ -243,11 +242,12 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, /* It is possible that there no initramfs is being loaded */ if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf, - &size, INT_MAX, + INT_MAX, READING_KEXEC_INITRAMFS); - if (ret) + if (ret < 0) goto out; - image->initrd_buf_len = size; + image->initrd_buf_len = ret; + ret = 0; } if (cmdline_len) { diff --git a/kernel/module.c b/kernel/module.c index 4218abd272ee..9faa6322f17b 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -4035,7 +4035,6 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) { struct load_info info = { }; - loff_t size; void *hdr = NULL; int err; @@ -4049,12 +4048,12 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |MODULE_INIT_IGNORE_VERMAGIC)) return -EINVAL; - err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX, + err = kernel_read_file_from_fd(fd, &hdr, INT_MAX, READING_MODULE); - if (err) + if (err < 0) return err; info.hdr = hdr; - info.len = size; + info.len = err; return load_module(&info, uargs, flags); } diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index f8869be45d8f..97661ffabc4e 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -171,16 +171,17 @@ int __init integrity_add_key(const unsigned int id, const void *data, int __init integrity_load_x509(const unsigned int id, const char *path) { void *data = NULL; - loff_t size; + size_t size; int rc; key_perm_t perm; - rc = kernel_read_file_from_path(path, &data, &size, 0, + rc = kernel_read_file_from_path(path, &data, 0, READING_X509_CERTIFICATE); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc; } + size = rc; perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index e13ffece3726..602f52717757 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -275,7 +275,7 @@ static ssize_t ima_read_policy(char *path) { void *data = NULL; char *datap; - loff_t size; + size_t size; int rc, pathlen = strlen(path); char *p; @@ -284,11 +284,13 @@ static ssize_t ima_read_policy(char *path) datap = path; strsep(&datap, "\n"); - rc = kernel_read_file_from_path(path, &data, &size, 0, READING_POLICY); + rc = kernel_read_file_from_path(path, &data, 0, READING_POLICY); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc; } + size = rc; + rc = 0; datap = data; while (size > 0 && (p = strsep(&datap, "\n"))) { -- cgit v1.2.3 From 885352881f11f1f3113d8eb877786bcb6d720544 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:19 -0700 Subject: fs/kernel_read_file: Add file_size output argument In preparation for adding partial read support, add an optional output argument to kernel_read_file*() that reports the file size so callers can reason more easily about their reading progress. Signed-off-by: Kees Cook Reviewed-by: Mimi Zohar Reviewed-by: Luis Chamberlain Reviewed-by: James Morris Acked-by: Scott Branden Link: https://lore.kernel.org/r/20201002173828.2099543-8-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/main.c | 1 + fs/kernel_read_file.c | 19 +++++++++++++------ include/linux/kernel_read_file.h | 4 ++++ kernel/kexec_file.c | 4 ++-- kernel/module.c | 2 +- security/integrity/digsig.c | 2 +- security/integrity/ima/ima_fs.c | 2 +- 7 files changed, 23 insertions(+), 11 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 6df1bdcfeb9d..d9a180148c4b 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -500,6 +500,7 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, /* load firmware files from the mount namespace of init */ rc = kernel_read_file_from_path_initns(path, &buffer, msize, + NULL, READING_FIRMWARE); if (rc < 0) { if (rc != -ENOENT) diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c index e21a76001fff..2e29c38eb4df 100644 --- a/fs/kernel_read_file.c +++ b/fs/kernel_read_file.c @@ -14,6 +14,8 @@ * @buf_size will be ignored) * @buf_size size of buf, if already allocated. If @buf not * allocated, this is the largest size to allocate. + * @file_size if non-NULL, the full size of @file will be + * written here. * @id the kernel_read_file_id identifying the type of * file contents being read (for LSMs to examine) * @@ -22,7 +24,8 @@ * */ int kernel_read_file(struct file *file, void **buf, - size_t buf_size, enum kernel_read_file_id id) + size_t buf_size, size_t *file_size, + enum kernel_read_file_id id) { loff_t i_size, pos; ssize_t bytes = 0; @@ -49,6 +52,8 @@ int kernel_read_file(struct file *file, void **buf, ret = -EFBIG; goto out; } + if (file_size) + *file_size = i_size; if (!*buf) *buf = allocated = vmalloc(i_size); @@ -91,7 +96,8 @@ out: EXPORT_SYMBOL_GPL(kernel_read_file); int kernel_read_file_from_path(const char *path, void **buf, - size_t buf_size, enum kernel_read_file_id id) + size_t buf_size, size_t *file_size, + enum kernel_read_file_id id) { struct file *file; int ret; @@ -103,14 +109,14 @@ int kernel_read_file_from_path(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, buf_size, id); + ret = kernel_read_file(file, buf, buf_size, file_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path); int kernel_read_file_from_path_initns(const char *path, void **buf, - size_t buf_size, + size_t buf_size, size_t *file_size, enum kernel_read_file_id id) { struct file *file; @@ -129,13 +135,14 @@ int kernel_read_file_from_path_initns(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, buf_size, id); + ret = kernel_read_file(file, buf, buf_size, file_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path_initns); int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id) { struct fd f = fdget(fd); @@ -144,7 +151,7 @@ int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, if (!f.file) goto out; - ret = kernel_read_file(f.file, buf, buf_size, id); + ret = kernel_read_file(f.file, buf, buf_size, file_size, id); out: fdput(f); return ret; diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h index 910039e7593e..023293eaf948 100644 --- a/include/linux/kernel_read_file.h +++ b/include/linux/kernel_read_file.h @@ -37,15 +37,19 @@ static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) int kernel_read_file(struct file *file, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); int kernel_read_file_from_path(const char *path, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); int kernel_read_file_from_path_initns(const char *path, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); #endif /* _LINUX_KERNEL_READ_FILE_H */ diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index b20cfde8a01d..ee51c1028658 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -222,7 +222,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, void *ldata; ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, - INT_MAX, READING_KEXEC_IMAGE); + INT_MAX, NULL, READING_KEXEC_IMAGE); if (ret < 0) return ret; image->kernel_buf_len = ret; @@ -242,7 +242,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, /* It is possible that there no initramfs is being loaded */ if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf, - INT_MAX, + INT_MAX, NULL, READING_KEXEC_INITRAMFS); if (ret < 0) goto out; diff --git a/kernel/module.c b/kernel/module.c index 9faa6322f17b..0f11eaed047e 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -4048,7 +4048,7 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |MODULE_INIT_IGNORE_VERMAGIC)) return -EINVAL; - err = kernel_read_file_from_fd(fd, &hdr, INT_MAX, + err = kernel_read_file_from_fd(fd, &hdr, INT_MAX, NULL, READING_MODULE); if (err < 0) return err; diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index 04f779c4f5ed..8a523dfd7fd7 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -175,7 +175,7 @@ int __init integrity_load_x509(const unsigned int id, const char *path) int rc; key_perm_t perm; - rc = kernel_read_file_from_path(path, &data, INT_MAX, + rc = kernel_read_file_from_path(path, &data, INT_MAX, NULL, READING_X509_CERTIFICATE); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 692b83e82edf..5fc56ccb6678 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -284,7 +284,7 @@ static ssize_t ima_read_policy(char *path) datap = path; strsep(&datap, "\n"); - rc = kernel_read_file_from_path(path, &data, INT_MAX, READING_POLICY); + rc = kernel_read_file_from_path(path, &data, INT_MAX, NULL, READING_POLICY); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc; -- cgit v1.2.3 From b64fcae74b6d6940d14243c963ab0089e8f0d82d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:20 -0700 Subject: LSM: Introduce kernel_post_load_data() hook There are a few places in the kernel where LSMs would like to have visibility into the contents of a kernel buffer that has been loaded or read. While security_kernel_post_read_file() (which includes the buffer) exists as a pairing for security_kernel_read_file(), no such hook exists to pair with security_kernel_load_data(). Earlier proposals for just using security_kernel_post_read_file() with a NULL file argument were rejected (i.e. "file" should always be valid for the security_..._file hooks, but it appears at least one case was left in the kernel during earlier refactoring. (This will be fixed in a subsequent patch.) Since not all cases of security_kernel_load_data() can have a single contiguous buffer made available to the LSM hook (e.g. kexec image segments are separately loaded), there needs to be a way for the LSM to reason about its expectations of the hook coverage. In order to handle this, add a "contents" argument to the "kernel_load_data" hook that indicates if the newly added "kernel_post_load_data" hook will be called with the full contents once loaded. That way, LSMs requiring full contents can choose to unilaterally reject "kernel_load_data" with contents=false (which is effectively the existing hook coverage), but when contents=true they can allow it and later evaluate the "kernel_post_load_data" hook once the buffer is loaded. With this change, LSMs can gain coverage over non-file-backed data loads (e.g. init_module(2) and firmware userspace helper), which will happen in subsequent patches. Additionally prepare IMA to start processing these cases. Signed-off-by: Kees Cook Reviewed-by: KP Singh Link: https://lore.kernel.org/r/20201002173828.2099543-9-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 2 +- drivers/base/firmware_loader/fallback_platform.c | 2 +- include/linux/ima.h | 13 +++++++++++-- include/linux/lsm_hook_defs.h | 4 +++- include/linux/lsm_hooks.h | 10 ++++++++++ include/linux/security.h | 14 ++++++++++++-- kernel/kexec.c | 2 +- kernel/module.c | 2 +- security/integrity/ima/ima_main.c | 24 +++++++++++++++++++++++- security/loadpin/loadpin.c | 2 +- security/security.c | 20 +++++++++++++++++--- security/selinux/hooks.c | 2 +- 12 files changed, 82 insertions(+), 15 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 283ca2de76d4..bff4717cc6b5 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -613,7 +613,7 @@ static bool fw_run_sysfs_fallback(u32 opt_flags) return false; /* Also permit LSMs and IMA to fail firmware sysfs fallback */ - ret = security_kernel_load_data(LOADING_FIRMWARE); + ret = security_kernel_load_data(LOADING_FIRMWARE, false); if (ret < 0) return false; diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c index 6958ab1a8059..a12c79d47efc 100644 --- a/drivers/base/firmware_loader/fallback_platform.c +++ b/drivers/base/firmware_loader/fallback_platform.c @@ -17,7 +17,7 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) if (!(opt_flags & FW_OPT_FALLBACK_PLATFORM)) return -ENOENT; - rc = security_kernel_load_data(LOADING_FIRMWARE); + rc = security_kernel_load_data(LOADING_FIRMWARE, false); if (rc) return rc; diff --git a/include/linux/ima.h b/include/linux/ima.h index 64804f78408b..af9fb8c5f16a 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -20,7 +20,9 @@ extern void ima_post_create_tmpfile(struct inode *inode); extern void ima_file_free(struct file *file); extern int ima_file_mmap(struct file *file, unsigned long prot); extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot); -extern int ima_load_data(enum kernel_load_data_id id); +extern int ima_load_data(enum kernel_load_data_id id, bool contents); +extern int ima_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id id, char *description); extern int ima_read_file(struct file *file, enum kernel_read_file_id id); extern int ima_post_read_file(struct file *file, void *buf, loff_t size, enum kernel_read_file_id id); @@ -78,7 +80,14 @@ static inline int ima_file_mprotect(struct vm_area_struct *vma, return 0; } -static inline int ima_load_data(enum kernel_load_data_id id) +static inline int ima_load_data(enum kernel_load_data_id id, bool contents) +{ + return 0; +} + +static inline int ima_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id id, + char *description) { return 0; } diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 2a8c74d99015..83c6f1f5cc1e 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -184,7 +184,9 @@ LSM_HOOK(void, LSM_RET_VOID, cred_getsecid, const struct cred *c, u32 *secid) LSM_HOOK(int, 0, kernel_act_as, struct cred *new, u32 secid) LSM_HOOK(int, 0, kernel_create_files_as, struct cred *new, struct inode *inode) LSM_HOOK(int, 0, kernel_module_request, char *kmod_name) -LSM_HOOK(int, 0, kernel_load_data, enum kernel_load_data_id id) +LSM_HOOK(int, 0, kernel_load_data, enum kernel_load_data_id id, bool contents) +LSM_HOOK(int, 0, kernel_post_load_data, char *buf, loff_t size, + enum kernel_read_file_id id, char *description) LSM_HOOK(int, 0, kernel_read_file, struct file *file, enum kernel_read_file_id id) LSM_HOOK(int, 0, kernel_post_read_file, struct file *file, char *buf, diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 9e2e3e63719d..6bb4f1a0158c 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -635,7 +635,17 @@ * @kernel_load_data: * Load data provided by userspace. * @id kernel load data identifier + * @contents if a subsequent @kernel_post_load_data will be called. * Return 0 if permission is granted. + * @kernel_post_load_data: + * Load data provided by a non-file source (usually userspace buffer). + * @buf pointer to buffer containing the data contents. + * @size length of the data contents. + * @id kernel load data identifier + * @description a text description of what was loaded, @id-specific + * Return 0 if permission is granted. + * This must be paired with a prior @kernel_load_data call that had + * @contents set to true. * @kernel_read_file: * Read a file specified by userspace. * @file contains the file structure pointing to the file being read diff --git a/include/linux/security.h b/include/linux/security.h index 42df0d9b4c37..51c8e4e6b7cc 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -387,7 +387,10 @@ void security_cred_getsecid(const struct cred *c, u32 *secid); int security_kernel_act_as(struct cred *new, u32 secid); int security_kernel_create_files_as(struct cred *new, struct inode *inode); int security_kernel_module_request(char *kmod_name); -int security_kernel_load_data(enum kernel_load_data_id id); +int security_kernel_load_data(enum kernel_load_data_id id, bool contents); +int security_kernel_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id id, + char *description); int security_kernel_read_file(struct file *file, enum kernel_read_file_id id); int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, enum kernel_read_file_id id); @@ -1014,7 +1017,14 @@ static inline int security_kernel_module_request(char *kmod_name) return 0; } -static inline int security_kernel_load_data(enum kernel_load_data_id id) +static inline int security_kernel_load_data(enum kernel_load_data_id id, bool contents) +{ + return 0; +} + +static inline int security_kernel_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id id, + char *description) { return 0; } diff --git a/kernel/kexec.c b/kernel/kexec.c index f977786fe498..c82c6c06f051 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -205,7 +205,7 @@ static inline int kexec_load_check(unsigned long nr_segments, return -EPERM; /* Permit LSMs and IMA to fail the kexec */ - result = security_kernel_load_data(LOADING_KEXEC_IMAGE); + result = security_kernel_load_data(LOADING_KEXEC_IMAGE, false); if (result < 0) return result; diff --git a/kernel/module.c b/kernel/module.c index 0f11eaed047e..f47209e0fde6 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3014,7 +3014,7 @@ static int copy_module_from_user(const void __user *umod, unsigned long len, if (info->len < sizeof(*(info->hdr))) return -ENOEXEC; - err = security_kernel_load_data(LOADING_MODULE); + err = security_kernel_load_data(LOADING_MODULE, false); if (err) return err; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 5f89970c5ab7..9dd9c5f4d736 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -676,6 +676,8 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, /** * ima_load_data - appraise decision based on policy * @id: kernel load data caller identifier + * @contents: whether the full contents will be available in a later + * call to ima_post_load_data(). * * Callers of this LSM hook can not measure, appraise, or audit the * data provided by userspace. Enforce policy rules requring a file @@ -683,7 +685,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, * * For permission return 0, otherwise return -EACCES. */ -int ima_load_data(enum kernel_load_data_id id) +int ima_load_data(enum kernel_load_data_id id, bool contents) { bool ima_enforce, sig_enforce; @@ -723,6 +725,26 @@ int ima_load_data(enum kernel_load_data_id id) return 0; } +/** + * ima_post_load_data - appraise decision based on policy + * @buf: pointer to in memory file contents + * @size: size of in memory file contents + * @id: kernel load data caller identifier + * @description: @id-specific description of contents + * + * Measure/appraise/audit in memory buffer based on policy. Policy rules + * are written in terms of a policy identifier. + * + * On success return 0. On integrity appraisal error, assuming the file + * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. + */ +int ima_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id load_id, + char *description) +{ + return 0; +} + /* * process_buffer_measurement - Measure the buffer to ima log. * @inode: inode associated with the object being measured (NULL for KEY_CHECK) diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c index 163c48216d13..28782412febb 100644 --- a/security/loadpin/loadpin.c +++ b/security/loadpin/loadpin.c @@ -177,7 +177,7 @@ static int loadpin_read_file(struct file *file, enum kernel_read_file_id id) return 0; } -static int loadpin_load_data(enum kernel_load_data_id id) +static int loadpin_load_data(enum kernel_load_data_id id, bool contents) { return loadpin_read_file(NULL, (enum kernel_read_file_id) id); } diff --git a/security/security.c b/security/security.c index 19d3150f68f4..531b855826fc 100644 --- a/security/security.c +++ b/security/security.c @@ -1695,17 +1695,31 @@ int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, } EXPORT_SYMBOL_GPL(security_kernel_post_read_file); -int security_kernel_load_data(enum kernel_load_data_id id) +int security_kernel_load_data(enum kernel_load_data_id id, bool contents) { int ret; - ret = call_int_hook(kernel_load_data, 0, id); + ret = call_int_hook(kernel_load_data, 0, id, contents); if (ret) return ret; - return ima_load_data(id); + return ima_load_data(id, contents); } EXPORT_SYMBOL_GPL(security_kernel_load_data); +int security_kernel_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id id, + char *description) +{ + int ret; + + ret = call_int_hook(kernel_post_load_data, 0, buf, size, id, + description); + if (ret) + return ret; + return ima_post_load_data(buf, size, id, description); +} +EXPORT_SYMBOL_GPL(security_kernel_post_load_data); + int security_task_fix_setuid(struct cred *new, const struct cred *old, int flags) { diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 96f5f8b3b9f0..558beee97d8d 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4018,7 +4018,7 @@ static int selinux_kernel_read_file(struct file *file, return rc; } -static int selinux_kernel_load_data(enum kernel_load_data_id id) +static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) { int rc = 0; -- cgit v1.2.3 From 4f2d99b06b73800a5fb5b33e1899272e87ed7093 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:21 -0700 Subject: firmware_loader: Use security_post_load_data() Now that security_post_load_data() is wired up, use it instead of the NULL file argument style of security_post_read_file(), and update the security_kernel_load_data() call to indicate that a security_kernel_post_load_data() call is expected. Wire up the IMA check to match earlier logic. Perhaps a generalized change to ima_post_load_data() might look something like this: return process_buffer_measurement(buf, size, kernel_load_data_id_str(load_id), read_idmap[load_id] ?: FILE_CHECK, 0, NULL); Signed-off-by: Kees Cook Reviewed-by: Mimi Zohar Link: https://lore.kernel.org/r/20201002173828.2099543-10-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 8 ++++---- drivers/base/firmware_loader/fallback_platform.c | 8 +++++++- security/integrity/ima/ima_main.c | 20 ++++++++++---------- 3 files changed, 21 insertions(+), 15 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index bff4717cc6b5..251d92fc8bae 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -272,9 +272,9 @@ static ssize_t firmware_loading_store(struct device *dev, dev_err(dev, "%s: map pages failed\n", __func__); else - rc = security_kernel_post_read_file(NULL, - fw_priv->data, fw_priv->size, - READING_FIRMWARE); + rc = security_kernel_post_load_data(fw_priv->data, + fw_priv->size, + LOADING_FIRMWARE, "blob"); /* * Same logic as fw_load_abort, only the DONE bit @@ -613,7 +613,7 @@ static bool fw_run_sysfs_fallback(u32 opt_flags) return false; /* Also permit LSMs and IMA to fail firmware sysfs fallback */ - ret = security_kernel_load_data(LOADING_FIRMWARE, false); + ret = security_kernel_load_data(LOADING_FIRMWARE, true); if (ret < 0) return false; diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c index a12c79d47efc..8bdf88043079 100644 --- a/drivers/base/firmware_loader/fallback_platform.c +++ b/drivers/base/firmware_loader/fallback_platform.c @@ -17,7 +17,7 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) if (!(opt_flags & FW_OPT_FALLBACK_PLATFORM)) return -ENOENT; - rc = security_kernel_load_data(LOADING_FIRMWARE, false); + rc = security_kernel_load_data(LOADING_FIRMWARE, true); if (rc) return rc; @@ -27,6 +27,12 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) if (fw_priv->data && size > fw_priv->allocated_size) return -ENOMEM; + + rc = security_kernel_post_load_data((u8 *)data, size, LOADING_FIRMWARE, + "platform"); + if (rc) + return rc; + if (!fw_priv->data) fw_priv->data = vmalloc(size); if (!fw_priv->data) diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 9dd9c5f4d736..6f2b8352573a 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -648,15 +648,6 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, enum ima_hooks func; u32 secid; - if (!file && read_id == READING_FIRMWARE) { - if ((ima_appraise & IMA_APPRAISE_FIRMWARE) && - (ima_appraise & IMA_APPRAISE_ENFORCE)) { - pr_err("Prevent firmware loading_store.\n"); - return -EACCES; /* INTEGRITY_UNKNOWN */ - } - return 0; - } - /* permit signed certs */ if (!file && read_id == READING_X509_CERTIFICATE) return 0; @@ -706,7 +697,7 @@ int ima_load_data(enum kernel_load_data_id id, bool contents) } break; case LOADING_FIRMWARE: - if (ima_enforce && (ima_appraise & IMA_APPRAISE_FIRMWARE)) { + if (ima_enforce && (ima_appraise & IMA_APPRAISE_FIRMWARE) && !contents) { pr_err("Prevent firmware sysfs fallback loading.\n"); return -EACCES; /* INTEGRITY_UNKNOWN */ } @@ -742,6 +733,15 @@ int ima_post_load_data(char *buf, loff_t size, enum kernel_load_data_id load_id, char *description) { + if (load_id == LOADING_FIRMWARE) { + if ((ima_appraise & IMA_APPRAISE_FIRMWARE) && + (ima_appraise & IMA_APPRAISE_ENFORCE)) { + pr_err("Prevent firmware loading_store.\n"); + return -EACCES; /* INTEGRITY_UNKNOWN */ + } + return 0; + } + return 0; } -- cgit v1.2.3 From 0fa8e084648779eeb8929ae004301b3acf3bad84 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:25 -0700 Subject: fs/kernel_file_read: Add "offset" arg for partial reads To perform partial reads, callers of kernel_read_file*() must have a non-NULL file_size argument and a preallocated buffer. The new "offset" argument can then be used to seek to specific locations in the file to fill the buffer to, at most, "buf_size" per call. Where possible, the LSM hooks can report whether a full file has been read or not so that the contents can be reasoned about. Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20201002173828.2099543-14-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/main.c | 2 +- fs/kernel_read_file.c | 78 +++++++++++++++++++++++++------------ include/linux/kernel_read_file.h | 8 ++-- kernel/kexec_file.c | 4 +- kernel/module.c | 2 +- security/integrity/digsig.c | 2 +- security/integrity/ima/ima_fs.c | 3 +- 7 files changed, 65 insertions(+), 34 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index d9a180148c4b..79f86466d472 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -499,7 +499,7 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, fw_priv->size = 0; /* load firmware files from the mount namespace of init */ - rc = kernel_read_file_from_path_initns(path, &buffer, msize, + rc = kernel_read_file_from_path_initns(path, 0, &buffer, msize, NULL, READING_FIRMWARE); if (rc < 0) { diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c index d73bc3fa710a..90d255fbdd9b 100644 --- a/fs/kernel_read_file.c +++ b/fs/kernel_read_file.c @@ -9,6 +9,7 @@ * kernel_read_file() - read file contents into a kernel buffer * * @file file to read from + * @offset where to start reading from (see below). * @buf pointer to a "void *" buffer for reading into (if * *@buf is NULL, a buffer will be allocated, and * @buf_size will be ignored) @@ -19,19 +20,31 @@ * @id the kernel_read_file_id identifying the type of * file contents being read (for LSMs to examine) * + * @offset must be 0 unless both @buf and @file_size are non-NULL + * (i.e. the caller must be expecting to read partial file contents + * via an already-allocated @buf, in at most @buf_size chunks, and + * will be able to determine when the entire file was read by + * checking @file_size). This isn't a recommended way to read a + * file, though, since it is possible that the contents might + * change between calls to kernel_read_file(). + * * Returns number of bytes read (no single read will be bigger * than INT_MAX), or negative on error. * */ -int kernel_read_file(struct file *file, void **buf, +int kernel_read_file(struct file *file, loff_t offset, void **buf, size_t buf_size, size_t *file_size, enum kernel_read_file_id id) { loff_t i_size, pos; - ssize_t bytes = 0; + size_t copied; void *allocated = NULL; + bool whole_file; int ret; + if (offset != 0 && (!*buf || !file_size)) + return -EINVAL; + if (!S_ISREG(file_inode(file)->i_mode)) return -EINVAL; @@ -39,19 +52,27 @@ int kernel_read_file(struct file *file, void **buf, if (ret) return ret; - ret = security_kernel_read_file(file, id, true); - if (ret) - goto out; - i_size = i_size_read(file_inode(file)); if (i_size <= 0) { ret = -EINVAL; goto out; } - if (i_size > INT_MAX || i_size > buf_size) { + /* The file is too big for sane activities. */ + if (i_size > INT_MAX) { + ret = -EFBIG; + goto out; + } + /* The entire file cannot be read in one buffer. */ + if (!file_size && offset == 0 && i_size > buf_size) { ret = -EFBIG; goto out; } + + whole_file = (offset == 0 && i_size <= buf_size); + ret = security_kernel_read_file(file, id, whole_file); + if (ret) + goto out; + if (file_size) *file_size = i_size; @@ -62,9 +83,14 @@ int kernel_read_file(struct file *file, void **buf, goto out; } - pos = 0; - while (pos < i_size) { - bytes = kernel_read(file, *buf + pos, i_size - pos, &pos); + pos = offset; + copied = 0; + while (copied < buf_size) { + ssize_t bytes; + size_t wanted = min_t(size_t, buf_size - copied, + i_size - pos); + + bytes = kernel_read(file, *buf + copied, wanted, &pos); if (bytes < 0) { ret = bytes; goto out_free; @@ -72,14 +98,17 @@ int kernel_read_file(struct file *file, void **buf, if (bytes == 0) break; + copied += bytes; } - if (pos != i_size) { - ret = -EIO; - goto out_free; - } + if (whole_file) { + if (pos != i_size) { + ret = -EIO; + goto out_free; + } - ret = security_kernel_post_read_file(file, *buf, i_size, id); + ret = security_kernel_post_read_file(file, *buf, i_size, id); + } out_free: if (ret < 0) { @@ -91,11 +120,11 @@ out_free: out: allow_write_access(file); - return ret == 0 ? pos : ret; + return ret == 0 ? copied : ret; } EXPORT_SYMBOL_GPL(kernel_read_file); -int kernel_read_file_from_path(const char *path, void **buf, +int kernel_read_file_from_path(const char *path, loff_t offset, void **buf, size_t buf_size, size_t *file_size, enum kernel_read_file_id id) { @@ -109,14 +138,15 @@ int kernel_read_file_from_path(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, buf_size, file_size, id); + ret = kernel_read_file(file, offset, buf, buf_size, file_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path); -int kernel_read_file_from_path_initns(const char *path, void **buf, - size_t buf_size, size_t *file_size, +int kernel_read_file_from_path_initns(const char *path, loff_t offset, + void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id) { struct file *file; @@ -135,14 +165,14 @@ int kernel_read_file_from_path_initns(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, buf_size, file_size, id); + ret = kernel_read_file(file, offset, buf, buf_size, file_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path_initns); -int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, - size_t *file_size, +int kernel_read_file_from_fd(int fd, loff_t offset, void **buf, + size_t buf_size, size_t *file_size, enum kernel_read_file_id id) { struct fd f = fdget(fd); @@ -151,7 +181,7 @@ int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, if (!f.file) goto out; - ret = kernel_read_file(f.file, buf, buf_size, file_size, id); + ret = kernel_read_file(f.file, offset, buf, buf_size, file_size, id); out: fdput(f); return ret; diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h index 023293eaf948..575ffa1031d3 100644 --- a/include/linux/kernel_read_file.h +++ b/include/linux/kernel_read_file.h @@ -35,19 +35,19 @@ static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) return kernel_read_file_str[id]; } -int kernel_read_file(struct file *file, +int kernel_read_file(struct file *file, loff_t offset, void **buf, size_t buf_size, size_t *file_size, enum kernel_read_file_id id); -int kernel_read_file_from_path(const char *path, +int kernel_read_file_from_path(const char *path, loff_t offset, void **buf, size_t buf_size, size_t *file_size, enum kernel_read_file_id id); -int kernel_read_file_from_path_initns(const char *path, +int kernel_read_file_from_path_initns(const char *path, loff_t offset, void **buf, size_t buf_size, size_t *file_size, enum kernel_read_file_id id); -int kernel_read_file_from_fd(int fd, +int kernel_read_file_from_fd(int fd, loff_t offset, void **buf, size_t buf_size, size_t *file_size, enum kernel_read_file_id id); diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index ee51c1028658..84f7316792a7 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -221,7 +221,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, int ret; void *ldata; - ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, + ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf, INT_MAX, NULL, READING_KEXEC_IMAGE); if (ret < 0) return ret; @@ -241,7 +241,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, #endif /* It is possible that there no initramfs is being loaded */ if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { - ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf, + ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf, INT_MAX, NULL, READING_KEXEC_INITRAMFS); if (ret < 0) diff --git a/kernel/module.c b/kernel/module.c index adfa21dd3842..9c578e44abe7 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -4054,7 +4054,7 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |MODULE_INIT_IGNORE_VERMAGIC)) return -EINVAL; - err = kernel_read_file_from_fd(fd, &hdr, INT_MAX, NULL, + err = kernel_read_file_from_fd(fd, 0, &hdr, INT_MAX, NULL, READING_MODULE); if (err < 0) return err; diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index 8a523dfd7fd7..0f518dcfde05 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -175,7 +175,7 @@ int __init integrity_load_x509(const unsigned int id, const char *path) int rc; key_perm_t perm; - rc = kernel_read_file_from_path(path, &data, INT_MAX, NULL, + rc = kernel_read_file_from_path(path, 0, &data, INT_MAX, NULL, READING_X509_CERTIFICATE); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 5fc56ccb6678..ea8ff8a07b36 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -284,7 +284,8 @@ static ssize_t ima_read_policy(char *path) datap = path; strsep(&datap, "\n"); - rc = kernel_read_file_from_path(path, &data, INT_MAX, NULL, READING_POLICY); + rc = kernel_read_file_from_path(path, 0, &data, INT_MAX, NULL, + READING_POLICY); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc; -- cgit v1.2.3 From 89287c169f8ff79d466b274da1d5c862e8b29152 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 2 Oct 2020 10:38:26 -0700 Subject: firmware: Store opt_flags in fw_priv Instead of passing opt_flags around so much, store it in the private structure so it can be examined by internals without needing to add more arguments to functions. Co-developed-by: Scott Branden Signed-off-by: Scott Branden Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20201002173828.2099543-15-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 11 ++++------- drivers/base/firmware_loader/fallback.h | 5 ++--- drivers/base/firmware_loader/fallback_platform.c | 4 ++-- drivers/base/firmware_loader/firmware.h | 3 ++- drivers/base/firmware_loader/main.c | 25 ++++++++++++++---------- 5 files changed, 25 insertions(+), 23 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 251d92fc8bae..c4765461a951 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -490,13 +490,11 @@ exit: /** * fw_load_sysfs_fallback() - load a firmware via the sysfs fallback mechanism * @fw_sysfs: firmware sysfs information for the firmware to load - * @opt_flags: flags of options, FW_OPT_* * @timeout: timeout to wait for the load * * In charge of constructing a sysfs fallback interface for firmware loading. **/ -static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, - u32 opt_flags, long timeout) +static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout) { int retval = 0; struct device *f_dev = &fw_sysfs->dev; @@ -518,7 +516,7 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, list_add(&fw_priv->pending_list, &pending_fw_head); mutex_unlock(&fw_lock); - if (opt_flags & FW_OPT_UEVENT) { + if (fw_priv->opt_flags & FW_OPT_UEVENT) { fw_priv->need_uevent = true; dev_set_uevent_suppress(f_dev, false); dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_name); @@ -580,10 +578,10 @@ static int fw_load_from_user_helper(struct firmware *firmware, } fw_sysfs->fw_priv = firmware->priv; - ret = fw_load_sysfs_fallback(fw_sysfs, opt_flags, timeout); + ret = fw_load_sysfs_fallback(fw_sysfs, timeout); if (!ret) - ret = assign_fw(firmware, device, opt_flags); + ret = assign_fw(firmware, device); out_unlock: usermodehelper_read_unlock(); @@ -625,7 +623,6 @@ static bool fw_run_sysfs_fallback(u32 opt_flags) * @fw: pointer to firmware image * @name: name of firmware file to look for * @device: device for which firmware is being loaded - * @opt_flags: options to control firmware loading behaviour * @ret: return value from direct lookup which triggered the fallback mechanism * * This function is called if direct lookup for the firmware failed, it enables diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h index 2afdb6adb23f..3af7205b302f 100644 --- a/drivers/base/firmware_loader/fallback.h +++ b/drivers/base/firmware_loader/fallback.h @@ -67,10 +67,9 @@ static inline void unregister_sysfs_loader(void) #endif /* CONFIG_FW_LOADER_USER_HELPER */ #ifdef CONFIG_EFI_EMBEDDED_FIRMWARE -int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags); +int firmware_fallback_platform(struct fw_priv *fw_priv); #else -static inline int firmware_fallback_platform(struct fw_priv *fw_priv, - u32 opt_flags) +static inline int firmware_fallback_platform(struct fw_priv *fw_priv) { return -ENOENT; } diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c index 8bdf88043079..00af99f0aff2 100644 --- a/drivers/base/firmware_loader/fallback_platform.c +++ b/drivers/base/firmware_loader/fallback_platform.c @@ -8,13 +8,13 @@ #include "fallback.h" #include "firmware.h" -int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) +int firmware_fallback_platform(struct fw_priv *fw_priv) { const u8 *data; size_t size; int rc; - if (!(opt_flags & FW_OPT_FALLBACK_PLATFORM)) + if (!(fw_priv->opt_flags & FW_OPT_FALLBACK_PLATFORM)) return -ENOENT; rc = security_kernel_load_data(LOADING_FIRMWARE, true); diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h index d08efc77cf16..f86de5d7e0d7 100644 --- a/drivers/base/firmware_loader/firmware.h +++ b/drivers/base/firmware_loader/firmware.h @@ -68,6 +68,7 @@ struct fw_priv { void *data; size_t size; size_t allocated_size; + u32 opt_flags; #ifdef CONFIG_FW_LOADER_PAGED_BUF bool is_paged_buf; struct page **pages; @@ -136,7 +137,7 @@ static inline void fw_state_done(struct fw_priv *fw_priv) __fw_state_set(fw_priv, FW_STATUS_DONE); } -int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags); +int assign_fw(struct firmware *fw, struct device *device); #ifdef CONFIG_FW_LOADER_PAGED_BUF void fw_free_paged_buf(struct fw_priv *fw_priv); diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 79f86466d472..78c8e44c08cb 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -168,7 +168,9 @@ static int fw_cache_piggyback_on_request(const char *name); static struct fw_priv *__allocate_fw_priv(const char *fw_name, struct firmware_cache *fwc, - void *dbuf, size_t size) + void *dbuf, + size_t size, + u32 opt_flags) { struct fw_priv *fw_priv; @@ -186,6 +188,7 @@ static struct fw_priv *__allocate_fw_priv(const char *fw_name, fw_priv->fwc = fwc; fw_priv->data = dbuf; fw_priv->allocated_size = size; + fw_priv->opt_flags = opt_flags; fw_state_init(fw_priv); #ifdef CONFIG_FW_LOADER_USER_HELPER INIT_LIST_HEAD(&fw_priv->pending_list); @@ -210,8 +213,10 @@ static struct fw_priv *__lookup_fw_priv(const char *fw_name) /* Returns 1 for batching firmware requests with the same name */ static int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc, - struct fw_priv **fw_priv, void *dbuf, - size_t size, u32 opt_flags) + struct fw_priv **fw_priv, + void *dbuf, + size_t size, + u32 opt_flags) { struct fw_priv *tmp; @@ -227,7 +232,7 @@ static int alloc_lookup_fw_priv(const char *fw_name, } } - tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size); + tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, opt_flags); if (tmp) { INIT_LIST_HEAD(&tmp->list); if (!(opt_flags & FW_OPT_NOCACHE)) @@ -640,7 +645,7 @@ static int fw_add_devm_name(struct device *dev, const char *name) } #endif -int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags) +int assign_fw(struct firmware *fw, struct device *device) { struct fw_priv *fw_priv = fw->priv; int ret; @@ -659,8 +664,8 @@ int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags) * should be fixed in devres or driver core. */ /* don't cache firmware handled without uevent */ - if (device && (opt_flags & FW_OPT_UEVENT) && - !(opt_flags & FW_OPT_NOCACHE)) { + if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) && + !(fw_priv->opt_flags & FW_OPT_NOCACHE)) { ret = fw_add_devm_name(device, fw_priv->fw_name); if (ret) { mutex_unlock(&fw_lock); @@ -672,7 +677,7 @@ int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags) * After caching firmware image is started, let it piggyback * on request firmware. */ - if (!(opt_flags & FW_OPT_NOCACHE) && + if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) && fw_priv->fwc->state == FW_LOADER_START_CACHE) { if (fw_cache_piggyback_on_request(fw_priv->fw_name)) kref_get(&fw_priv->ref); @@ -783,7 +788,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name, #endif if (ret == -ENOENT) - ret = firmware_fallback_platform(fw->priv, opt_flags); + ret = firmware_fallback_platform(fw->priv); if (ret) { if (!(opt_flags & FW_OPT_NO_WARN)) @@ -792,7 +797,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name, name, ret); ret = firmware_fallback_sysfs(fw, name, device, opt_flags, ret); } else - ret = assign_fw(fw, device, opt_flags); + ret = assign_fw(fw, device); out: if (ret < 0) { -- cgit v1.2.3 From 59cdb23ca2dfef3b93411d1105409dfe9cd1f62f Mon Sep 17 00:00:00 2001 From: Scott Branden Date: Fri, 2 Oct 2020 10:38:27 -0700 Subject: firmware: Add request_partial_firmware_into_buf() Add request_partial_firmware_into_buf() to allow for portions of a firmware file to be read into a buffer. This is needed when large firmware must be loaded in portions from a file on memory constrained systems. Signed-off-by: Scott Branden Co-developed-by: Kees Cook Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20201002173828.2099543-16-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/firmware.h | 4 ++ drivers/base/firmware_loader/main.c | 101 ++++++++++++++++++++++++++------ include/linux/firmware.h | 12 ++++ 3 files changed, 99 insertions(+), 18 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h index f86de5d7e0d7..63bd29fdcb9c 100644 --- a/drivers/base/firmware_loader/firmware.h +++ b/drivers/base/firmware_loader/firmware.h @@ -32,6 +32,8 @@ * @FW_OPT_FALLBACK_PLATFORM: Enable fallback to device fw copy embedded in * the platform's main firmware. If both this fallback and the sysfs * fallback are enabled, then this fallback will be tried first. + * @FW_OPT_PARTIAL: Allow partial read of firmware instead of needing to read + * entire file. */ enum fw_opt { FW_OPT_UEVENT = BIT(0), @@ -41,6 +43,7 @@ enum fw_opt { FW_OPT_NOCACHE = BIT(4), FW_OPT_NOFALLBACK_SYSFS = BIT(5), FW_OPT_FALLBACK_PLATFORM = BIT(6), + FW_OPT_PARTIAL = BIT(7), }; enum fw_status { @@ -68,6 +71,7 @@ struct fw_priv { void *data; size_t size; size_t allocated_size; + size_t offset; u32 opt_flags; #ifdef CONFIG_FW_LOADER_PAGED_BUF bool is_paged_buf; diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 78c8e44c08cb..78355095e00d 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -170,10 +170,19 @@ static struct fw_priv *__allocate_fw_priv(const char *fw_name, struct firmware_cache *fwc, void *dbuf, size_t size, + size_t offset, u32 opt_flags) { struct fw_priv *fw_priv; + /* For a partial read, the buffer must be preallocated. */ + if ((opt_flags & FW_OPT_PARTIAL) && !dbuf) + return NULL; + + /* Only partial reads are allowed to use an offset. */ + if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL)) + return NULL; + fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC); if (!fw_priv) return NULL; @@ -188,6 +197,7 @@ static struct fw_priv *__allocate_fw_priv(const char *fw_name, fw_priv->fwc = fwc; fw_priv->data = dbuf; fw_priv->allocated_size = size; + fw_priv->offset = offset; fw_priv->opt_flags = opt_flags; fw_state_init(fw_priv); #ifdef CONFIG_FW_LOADER_USER_HELPER @@ -216,12 +226,17 @@ static int alloc_lookup_fw_priv(const char *fw_name, struct fw_priv **fw_priv, void *dbuf, size_t size, + size_t offset, u32 opt_flags) { struct fw_priv *tmp; spin_lock(&fwc->lock); - if (!(opt_flags & FW_OPT_NOCACHE)) { + /* + * Do not merge requests that are marked to be non-cached or + * are performing partial reads. + */ + if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) { tmp = __lookup_fw_priv(fw_name); if (tmp) { kref_get(&tmp->ref); @@ -232,7 +247,7 @@ static int alloc_lookup_fw_priv(const char *fw_name, } } - tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, opt_flags); + tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags); if (tmp) { INIT_LIST_HEAD(&tmp->list); if (!(opt_flags & FW_OPT_NOCACHE)) @@ -490,6 +505,9 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, return -ENOMEM; for (i = 0; i < ARRAY_SIZE(fw_path); i++) { + size_t file_size = 0; + size_t *file_size_ptr = NULL; + /* skip the unset customized path */ if (!fw_path[i][0]) continue; @@ -503,9 +521,18 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, fw_priv->size = 0; + /* + * The total file size is only examined when doing a partial + * read; the "full read" case needs to fail if the whole + * firmware was not completely loaded. + */ + if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer) + file_size_ptr = &file_size; + /* load firmware files from the mount namespace of init */ - rc = kernel_read_file_from_path_initns(path, 0, &buffer, msize, - NULL, + rc = kernel_read_file_from_path_initns(path, fw_priv->offset, + &buffer, msize, + file_size_ptr, READING_FIRMWARE); if (rc < 0) { if (rc != -ENOENT) @@ -696,7 +723,7 @@ int assign_fw(struct firmware *fw, struct device *device) static int _request_firmware_prepare(struct firmware **firmware_p, const char *name, struct device *device, void *dbuf, size_t size, - u32 opt_flags) + size_t offset, u32 opt_flags) { struct firmware *firmware; struct fw_priv *fw_priv; @@ -715,7 +742,7 @@ _request_firmware_prepare(struct firmware **firmware_p, const char *name, } ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size, - opt_flags); + offset, opt_flags); /* * bind with 'priv' now to avoid warning in failure path @@ -762,9 +789,10 @@ static void fw_abort_batch_reqs(struct firmware *fw) static int _request_firmware(const struct firmware **firmware_p, const char *name, struct device *device, void *buf, size_t size, - u32 opt_flags) + size_t offset, u32 opt_flags) { struct firmware *fw = NULL; + bool nondirect = false; int ret; if (!firmware_p) @@ -776,18 +804,22 @@ _request_firmware(const struct firmware **firmware_p, const char *name, } ret = _request_firmware_prepare(&fw, name, device, buf, size, - opt_flags); + offset, opt_flags); if (ret <= 0) /* error or already assigned */ goto out; ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL); + + /* Only full reads can support decompression, platform, and sysfs. */ + if (!(opt_flags & FW_OPT_PARTIAL)) + nondirect = true; + #ifdef CONFIG_FW_LOADER_COMPRESS - if (ret == -ENOENT) + if (ret == -ENOENT && nondirect) ret = fw_get_filesystem_firmware(device, fw->priv, ".xz", fw_decompress_xz); #endif - - if (ret == -ENOENT) + if (ret == -ENOENT && nondirect) ret = firmware_fallback_platform(fw->priv); if (ret) { @@ -795,7 +827,9 @@ _request_firmware(const struct firmware **firmware_p, const char *name, dev_warn(device, "Direct firmware load for %s failed with error %d\n", name, ret); - ret = firmware_fallback_sysfs(fw, name, device, opt_flags, ret); + if (nondirect) + ret = firmware_fallback_sysfs(fw, name, device, + opt_flags, ret); } else ret = assign_fw(fw, device); @@ -838,7 +872,7 @@ request_firmware(const struct firmware **firmware_p, const char *name, /* Need to pin this module until return */ __module_get(THIS_MODULE); - ret = _request_firmware(firmware_p, name, device, NULL, 0, + ret = _request_firmware(firmware_p, name, device, NULL, 0, 0, FW_OPT_UEVENT); module_put(THIS_MODULE); return ret; @@ -865,7 +899,7 @@ int firmware_request_nowarn(const struct firmware **firmware, const char *name, /* Need to pin this module until return */ __module_get(THIS_MODULE); - ret = _request_firmware(firmware, name, device, NULL, 0, + ret = _request_firmware(firmware, name, device, NULL, 0, 0, FW_OPT_UEVENT | FW_OPT_NO_WARN); module_put(THIS_MODULE); return ret; @@ -889,7 +923,7 @@ int request_firmware_direct(const struct firmware **firmware_p, int ret; __module_get(THIS_MODULE); - ret = _request_firmware(firmware_p, name, device, NULL, 0, + ret = _request_firmware(firmware_p, name, device, NULL, 0, 0, FW_OPT_UEVENT | FW_OPT_NO_WARN | FW_OPT_NOFALLBACK_SYSFS); module_put(THIS_MODULE); @@ -914,7 +948,7 @@ int firmware_request_platform(const struct firmware **firmware, /* Need to pin this module until return */ __module_get(THIS_MODULE); - ret = _request_firmware(firmware, name, device, NULL, 0, + ret = _request_firmware(firmware, name, device, NULL, 0, 0, FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM); module_put(THIS_MODULE); return ret; @@ -970,13 +1004,44 @@ request_firmware_into_buf(const struct firmware **firmware_p, const char *name, return -EOPNOTSUPP; __module_get(THIS_MODULE); - ret = _request_firmware(firmware_p, name, device, buf, size, + ret = _request_firmware(firmware_p, name, device, buf, size, 0, FW_OPT_UEVENT | FW_OPT_NOCACHE); module_put(THIS_MODULE); return ret; } EXPORT_SYMBOL(request_firmware_into_buf); +/** + * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer + * @firmware_p: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded and DMA region allocated + * @buf: address of buffer to load firmware into + * @size: size of buffer + * @offset: offset into file to read + * + * This function works pretty much like request_firmware_into_buf except + * it allows a partial read of the file. + */ +int +request_partial_firmware_into_buf(const struct firmware **firmware_p, + const char *name, struct device *device, + void *buf, size_t size, size_t offset) +{ + int ret; + + if (fw_cache_is_setup(device, name)) + return -EOPNOTSUPP; + + __module_get(THIS_MODULE); + ret = _request_firmware(firmware_p, name, device, buf, size, offset, + FW_OPT_UEVENT | FW_OPT_NOCACHE | + FW_OPT_PARTIAL); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL(request_partial_firmware_into_buf); + /** * release_firmware() - release the resource associated with a firmware image * @fw: firmware resource to release @@ -1009,7 +1074,7 @@ static void request_firmware_work_func(struct work_struct *work) fw_work = container_of(work, struct firmware_work, work); - _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, + _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0, fw_work->opt_flags); fw_work->cont(fw, fw_work->context); put_device(fw_work->device); /* taken in request_firmware_nowait() */ diff --git a/include/linux/firmware.h b/include/linux/firmware.h index cb3e2c06ed8a..c15acadc6cf4 100644 --- a/include/linux/firmware.h +++ b/include/linux/firmware.h @@ -53,6 +53,9 @@ int request_firmware_direct(const struct firmware **fw, const char *name, struct device *device); int request_firmware_into_buf(const struct firmware **firmware_p, const char *name, struct device *device, void *buf, size_t size); +int request_partial_firmware_into_buf(const struct firmware **firmware_p, + const char *name, struct device *device, + void *buf, size_t size, size_t offset); void release_firmware(const struct firmware *fw); #else @@ -102,6 +105,15 @@ static inline int request_firmware_into_buf(const struct firmware **firmware_p, return -EINVAL; } +static inline int request_partial_firmware_into_buf + (const struct firmware **firmware_p, + const char *name, + struct device *device, + void *buf, size_t size, size_t offset) +{ + return -EINVAL; +} + #endif int firmware_request_cache(struct device *device, const char *name); -- cgit v1.2.3 From dba8648dcab90564b8a11c952c06a9e1153506fb Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 6 Oct 2020 15:21:33 +0200 Subject: firmware_loader: fix a kernel-doc markup The firmware_fallback_sysfs had some changes at their parameters. Those ended by dropping a documentation for such parameter. Re-add it. Fixes: 89287c169f8f ("firmware: Store opt_flags in fw_priv") Fixes: c2c076166b58 ("firmware_loader: change enum fw_opt to u32") Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/23ec441bb9c206f5899b5d64d34e5c9f6add5fd9.1601990386.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_loader/fallback.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index c4765461a951..355a0e98fa7e 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -623,6 +623,8 @@ static bool fw_run_sysfs_fallback(u32 opt_flags) * @fw: pointer to firmware image * @name: name of firmware file to look for * @device: device for which firmware is being loaded + * @opt_flags: options to control firmware loading behaviour, as defined by + * &enum fw_opt * @ret: return value from direct lookup which triggered the fallback mechanism * * This function is called if direct lookup for the firmware failed, it enables -- cgit v1.2.3