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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-18 22:35:51 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-18 22:35:51 +0300 |
commit | 5e857ce6eae7ca21b2055cca4885545e29228fe2 (patch) | |
tree | b3b5b9a88222fe189ba44989a84932c7258c64c4 /include/linux | |
parent | 670d0a4b10704667765f7d18f7592993d02783aa (diff) | |
parent | 0c389d89abc28edf70ae847ee2fa55acb267b826 (diff) | |
download | linux-5e857ce6eae7ca21b2055cca4885545e29228fe2.tar.xz |
Merge branch 'hch' (maccess patches from Christoph Hellwig)
Merge non-faulting memory access cleanups from Christoph Hellwig:
"Andrew and I decided to drop the patches implementing your suggested
rename of the probe_kernel_* and probe_user_* helpers from -mm as
there were way to many conflicts.
After -rc1 might be a good time for this as all the conflicts are
resolved now"
This also adds a type safety checking patch on top of the renaming
series to make the subtle behavioral difference between 'get_user()' and
'get_kernel_nofault()' less potentially dangerous and surprising.
* emailed patches from Christoph Hellwig <hch@lst.de>:
maccess: make get_kernel_nofault() check for minimal type compatibility
maccess: rename probe_kernel_address to get_kernel_nofault
maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault
maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/uaccess.h | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 7bcadca22100..0a76ddc07d59 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -301,13 +301,14 @@ copy_struct_from_user(void *dst, size_t ksize, const void __user *src, return 0; } -bool probe_kernel_read_allowed(const void *unsafe_src, size_t size); +bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size); -extern long probe_kernel_read(void *dst, const void *src, size_t size); -extern long probe_user_read(void *dst, const void __user *src, size_t size); +long copy_from_kernel_nofault(void *dst, const void *src, size_t size); +long notrace copy_to_kernel_nofault(void *dst, const void *src, size_t size); -extern long notrace probe_kernel_write(void *dst, const void *src, size_t size); -extern long notrace probe_user_write(void __user *dst, const void *src, size_t size); +long copy_from_user_nofault(void *dst, const void __user *src, size_t size); +long notrace copy_to_user_nofault(void __user *dst, const void *src, + size_t size); long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count); @@ -317,14 +318,16 @@ long strncpy_from_user_nofault(char *dst, const void __user *unsafe_addr, long strnlen_user_nofault(const void __user *unsafe_addr, long count); /** - * probe_kernel_address(): safely attempt to read from a location - * @addr: address to read from - * @retval: read into this variable + * get_kernel_nofault(): safely attempt to read from a location + * @val: read into this variable + * @ptr: address to read from * * Returns 0 on success, or -EFAULT. */ -#define probe_kernel_address(addr, retval) \ - probe_kernel_read(&retval, addr, sizeof(retval)) +#define get_kernel_nofault(val, ptr) ({ \ + const typeof(val) *__gk_ptr = (ptr); \ + copy_from_kernel_nofault(&(val), __gk_ptr, sizeof(val));\ +}) #ifndef user_access_begin #define user_access_begin(ptr,len) access_ok(ptr, len) |