The exported interface copy_oldmem_page_encrypted() passes user pointer without __user annotation and does unnecessary user/kernel pointer conversions during the pointer propagation.
Hence it is modified to have a new parameter for user pointer. The other similar interface copy_oldmem_page() will be updated in the subsequent patches. x86_64 crash dump is also modified to use this modified interface. No functionality change intended. Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Young <[email protected]> Cc: Baoquan He <[email protected]> Cc: Vivek Goyal <[email protected]> Cc: x86 <[email protected]> Cc: kexec <[email protected]> Cc: linux-fsdevel <[email protected]> Signed-off-by: Amit Daniel Kachhap <[email protected]> --- arch/x86/kernel/crash_dump_64.c | 12 +++++++++--- fs/proc/vmcore.c | 24 +++++++++++------------- include/linux/crash_dump.h | 6 +++--- 3 files changed, 23 insertions(+), 19 deletions(-) diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c index 6433513ef43a..99cd505628fa 100644 --- a/arch/x86/kernel/crash_dump_64.c +++ b/arch/x86/kernel/crash_dump_64.c @@ -66,10 +66,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, * memory with the encryption mask set to accommodate kdump on SME-enabled * machines. */ -ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize, - unsigned long offset, int userbuf) +ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char __user *ubuf, + char *kbuf, size_t csize, + unsigned long offset) { - return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, true); + if (ubuf) + return __copy_oldmem_page(pfn, (__force char *)ubuf, csize, + offset, 1, true); + else + return __copy_oldmem_page(pfn, kbuf, csize, + offset, 0, true); } ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index 39b4353bd37c..fa4492ef6124 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -168,16 +168,10 @@ ssize_t read_from_oldmem(char __user *ubuf, char *kbuf, size_t count, else if (clear_user(ubuf, nr_bytes)) tmp = -EFAULT; } else { - if (encrypted && ubuf) - tmp = copy_oldmem_page_encrypted(pfn, - (__force char *)ubuf, - nr_bytes, - offset, 1); - else if (encrypted && kbuf) - tmp = copy_oldmem_page_encrypted(pfn, - kbuf, - nr_bytes, - offset, 0); + if (encrypted) + tmp = copy_oldmem_page_encrypted(pfn, ubuf, + kbuf, nr_bytes, + offset); else if (ubuf) tmp = copy_oldmem_page(pfn, (__force char *)ubuf, nr_bytes, offset, 1); @@ -247,10 +241,14 @@ int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma, * Architectures which support memory encryption override this. */ ssize_t __weak -copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize, - unsigned long offset, int userbuf) +copy_oldmem_page_encrypted(unsigned long pfn, char __user *ubuf, char *kbuf, + size_t csize, unsigned long offset) { - return copy_oldmem_page(pfn, buf, csize, offset, userbuf); + if (ubuf) + return copy_oldmem_page(pfn, (__force char *)ubuf, csize, + offset, 1); + else + return copy_oldmem_page(pfn, kbuf, csize, offset, 0); } /* diff --git a/include/linux/crash_dump.h b/include/linux/crash_dump.h index eb0ed423ccc8..36a7f08f4ad2 100644 --- a/include/linux/crash_dump.h +++ b/include/linux/crash_dump.h @@ -26,9 +26,9 @@ extern int remap_oldmem_pfn_range(struct vm_area_struct *vma, extern ssize_t copy_oldmem_page(unsigned long, char *, size_t, unsigned long, int); -extern ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf, - size_t csize, unsigned long offset, - int userbuf); +extern ssize_t copy_oldmem_page_encrypted(unsigned long pfn, + char __user *ubuf, char *kbuf, + size_t csize, unsigned long offset); void vmcore_cleanup(void); -- 2.17.1 _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
