diff options
author | Christoph Hellwig <hch@lst.de> | 2020-06-17 10:37:53 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-17 20:57:41 +0300 |
commit | fe557319aa06c23cffc9346000f119547e0f289a (patch) | |
tree | 575c46f0a54b789a7f942e3366ade6f0f90f6212 /mm | |
parent | b3a9e3b9622ae10064826dccb4f7a52bd88c7407 (diff) |
maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/debug.c | 8 | ||||
-rw-r--r-- | mm/maccess.c | 49 | ||||
-rw-r--r-- | mm/rodata_test.c | 2 | ||||
-rw-r--r-- | mm/slub.c | 2 |
4 files changed, 31 insertions, 30 deletions
diff --git a/mm/debug.c b/mm/debug.c index b5b1de8c71ac..4f376514744d 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -120,9 +120,9 @@ void __dump_page(struct page *page, const char *reason) * mapping can be invalid pointer and we don't want to crash * accessing it, so probe everything depending on it carefully */ - if (probe_kernel_read(&host, &mapping->host, + if (copy_from_kernel_nofault(&host, &mapping->host, sizeof(struct inode *)) || - probe_kernel_read(&a_ops, &mapping->a_ops, + copy_from_kernel_nofault(&a_ops, &mapping->a_ops, sizeof(struct address_space_operations *))) { pr_warn("failed to read mapping->host or a_ops, mapping not a valid kernel address?\n"); goto out_mapping; @@ -133,7 +133,7 @@ void __dump_page(struct page *page, const char *reason) goto out_mapping; } - if (probe_kernel_read(&dentry_first, + if (copy_from_kernel_nofault(&dentry_first, &host->i_dentry.first, sizeof(struct hlist_node *))) { pr_warn("mapping->a_ops:%ps with invalid mapping->host inode address %px\n", a_ops, host); @@ -146,7 +146,7 @@ void __dump_page(struct page *page, const char *reason) } dentry_ptr = container_of(dentry_first, struct dentry, d_u.d_alias); - if (probe_kernel_read(&dentry, dentry_ptr, + if (copy_from_kernel_nofault(&dentry, dentry_ptr, sizeof(struct dentry))) { pr_warn("mapping->aops:%ps with invalid mapping->host->i_dentry.first %px\n", a_ops, dentry_ptr); diff --git a/mm/maccess.c b/mm/maccess.c index 88845eda5047..cc5d8c6233c0 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -6,14 +6,15 @@ #include <linux/mm.h> #include <linux/uaccess.h> -bool __weak probe_kernel_read_allowed(const void *unsafe_src, size_t size) +bool __weak copy_from_kernel_nofault_allowed(const void *unsafe_src, + size_t size) { return true; } #ifdef HAVE_GET_KERNEL_NOFAULT -#define probe_kernel_read_loop(dst, src, len, type, err_label) \ +#define copy_from_kernel_nofault_loop(dst, src, len, type, err_label) \ while (len >= sizeof(type)) { \ __get_kernel_nofault(dst, src, type, err_label); \ dst += sizeof(type); \ @@ -21,25 +22,25 @@ bool __weak probe_kernel_read_allowed(const void *unsafe_src, size_t size) len -= sizeof(type); \ } -long probe_kernel_read(void *dst, const void *src, size_t size) +long copy_from_kernel_nofault(void *dst, const void *src, size_t size) { - if (!probe_kernel_read_allowed(src, size)) + if (!copy_from_kernel_nofault_allowed(src, size)) return -ERANGE; pagefault_disable(); - probe_kernel_read_loop(dst, src, size, u64, Efault); - probe_kernel_read_loop(dst, src, size, u32, Efault); - probe_kernel_read_loop(dst, src, size, u16, Efault); - probe_kernel_read_loop(dst, src, size, u8, Efault); + copy_from_kernel_nofault_loop(dst, src, size, u64, Efault); + copy_from_kernel_nofault_loop(dst, src, size, u32, Efault); + copy_from_kernel_nofault_loop(dst, src, size, u16, Efault); + copy_from_kernel_nofault_loop(dst, src, size, u8, Efault); pagefault_enable(); return 0; Efault: pagefault_enable(); return -EFAULT; } -EXPORT_SYMBOL_GPL(probe_kernel_read); +EXPORT_SYMBOL_GPL(copy_from_kernel_nofault); -#define probe_kernel_write_loop(dst, src, len, type, err_label) \ +#define copy_to_kernel_nofault_loop(dst, src, len, type, err_label) \ while (len >= sizeof(type)) { \ __put_kernel_nofault(dst, src, type, err_label); \ dst += sizeof(type); \ @@ -47,13 +48,13 @@ EXPORT_SYMBOL_GPL(probe_kernel_read); len -= sizeof(type); \ } -long probe_kernel_write(void *dst, const void *src, size_t size) +long copy_to_kernel_nofault(void *dst, const void *src, size_t size) { pagefault_disable(); - probe_kernel_write_loop(dst, src, size, u64, Efault); - probe_kernel_write_loop(dst, src, size, u32, Efault); - probe_kernel_write_loop(dst, src, size, u16, Efault); - probe_kernel_write_loop(dst, src, size, u8, Efault); + copy_to_kernel_nofault_loop(dst, src, size, u64, Efault); + copy_to_kernel_nofault_loop(dst, src, size, u32, Efault); + copy_to_kernel_nofault_loop(dst, src, size, u16, Efault); + copy_to_kernel_nofault_loop(dst, src, size, u8, Efault); pagefault_enable(); return 0; Efault: @@ -67,7 +68,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count) if (unlikely(count <= 0)) return 0; - if (!probe_kernel_read_allowed(unsafe_addr, count)) + if (!copy_from_kernel_nofault_allowed(unsafe_addr, count)) return -ERANGE; pagefault_disable(); @@ -87,7 +88,7 @@ Efault: } #else /* HAVE_GET_KERNEL_NOFAULT */ /** - * probe_kernel_read(): safely attempt to read from kernel-space + * copy_from_kernel_nofault(): safely attempt to read from kernel-space * @dst: pointer to the buffer that shall take the data * @src: address to read from * @size: size of the data chunk @@ -98,15 +99,15 @@ Efault: * * We ensure that the copy_from_user is executed in atomic context so that * do_page_fault() doesn't attempt to take mmap_lock. This makes - * probe_kernel_read() suitable for use within regions where the caller + * copy_from_kernel_nofault() suitable for use within regions where the caller * already holds mmap_lock, or other locks which nest inside mmap_lock. */ -long probe_kernel_read(void *dst, const void *src, size_t size) +long copy_from_kernel_nofault(void *dst, const void *src, size_t size) { long ret; mm_segment_t old_fs = get_fs(); - if (!probe_kernel_read_allowed(src, size)) + if (!copy_from_kernel_nofault_allowed(src, size)) return -ERANGE; set_fs(KERNEL_DS); @@ -120,10 +121,10 @@ long probe_kernel_read(void *dst, const void *src, size_t size) return -EFAULT; return 0; } -EXPORT_SYMBOL_GPL(probe_kernel_read); +EXPORT_SYMBOL_GPL(copy_from_kernel_nofault); /** - * probe_kernel_write(): safely attempt to write to a location + * copy_to_kernel_nofault(): safely attempt to write to a location * @dst: address to write to * @src: pointer to the data that shall be written * @size: size of the data chunk @@ -131,7 +132,7 @@ EXPORT_SYMBOL_GPL(probe_kernel_read); * Safely write to address @dst from the buffer at @src. If a kernel fault * happens, handle that and return -EFAULT. */ -long probe_kernel_write(void *dst, const void *src, size_t size) +long copy_to_kernel_nofault(void *dst, const void *src, size_t size) { long ret; mm_segment_t old_fs = get_fs(); @@ -174,7 +175,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count) if (unlikely(count <= 0)) return 0; - if (!probe_kernel_read_allowed(unsafe_addr, count)) + if (!copy_from_kernel_nofault_allowed(unsafe_addr, count)) return -ERANGE; set_fs(KERNEL_DS); diff --git a/mm/rodata_test.c b/mm/rodata_test.c index 5e313fa93276..2a99df7beeb3 100644 --- a/mm/rodata_test.c +++ b/mm/rodata_test.c @@ -25,7 +25,7 @@ void rodata_test(void) } /* test 2: write to the variable; this should fault */ - if (!probe_kernel_write((void *)&rodata_test_data, + if (!copy_to_kernel_nofault((void *)&rodata_test_data, (void *)&zero, sizeof(zero))) { pr_err("test data was not read only\n"); return; diff --git a/mm/slub.c b/mm/slub.c index b8f798b50d44..fe81773fd97e 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -292,7 +292,7 @@ static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) return get_freepointer(s, object); freepointer_addr = (unsigned long)object + s->offset; - probe_kernel_read(&p, (void **)freepointer_addr, sizeof(p)); + copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p)); return freelist_ptr(s, p, freepointer_addr); } |