diff --git a/kernel/kexec.c b/kernel/kexec.c index 9c7aef8f4bb6..b5e40f069768 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -19,26 +19,9 @@ #include "kexec_internal.h" -static int copy_user_segment_list(struct kimage *image, - unsigned long nr_segments, - struct kexec_segment __user *segments) -{ - int ret; - size_t segment_bytes; - - /* Read in the segments */ - image->nr_segments = nr_segments; - segment_bytes = nr_segments * sizeof(*segments); - ret = copy_from_user(image->segment, segments, segment_bytes); - if (ret) - ret = -EFAULT; - - return ret; -} - static int kimage_alloc_init(struct kimage **rimage, unsigned long entry, unsigned long nr_segments, - struct kexec_segment __user *segments, + struct kexec_segment *segments, unsigned long flags) { int ret; @@ -58,10 +41,8 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry, return -ENOMEM; image->start = entry; - - ret = copy_user_segment_list(image, nr_segments, segments); - if (ret) - goto out_free_image; + image->nr_segments = nr_segments; + memcpy(image->segment, segments, nr_segments * sizeof(*segments)); if (kexec_on_panic) { /* Enable special crash kernel control page alloc policy. */ @@ -104,7 +85,7 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry, } static int do_kexec_load(unsigned long entry, unsigned long nr_segments, - struct kexec_segment __user *segments, unsigned long flags) + struct kexec_segment *segments, unsigned long flags) { struct kimage **dest_image, *image; unsigned long i; @@ -250,7 +231,8 @@ static inline int kexec_load_check(unsigned long nr_segments, SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, struct kexec_segment __user *, segments, unsigned long, flags) { - int result; + struct kexec_segment *ksegments; + unsigned long result; result = kexec_load_check(nr_segments, flags); if (result) @@ -261,7 +243,12 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, ((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT)) return -EINVAL; - result = do_kexec_load(entry, nr_segments, segments, flags); + ksegments = memdup_user(segments, nr_segments * sizeof(ksegments[0])); + if (IS_ERR(ksegments)) + return PTR_ERR(ksegments); + + result = do_kexec_load(entry, nr_segments, ksegments, flags); + kfree(ksegments); return result; } @@ -273,7 +260,7 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry, compat_ulong_t, flags) { struct compat_kexec_segment in; - struct kexec_segment out, __user *ksegments; + struct kexec_segment *ksegments; unsigned long i, result; result = kexec_load_check(nr_segments, flags); @@ -286,24 +273,26 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry, if ((flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_DEFAULT) return -EINVAL; - ksegments = compat_alloc_user_space(nr_segments * sizeof(out)); + ksegments = kmalloc_array(nr_segments, sizeof(ksegments[0]), + GFP_KERNEL); + if (!ksegments) + return -ENOMEM; + for (i = 0; i < nr_segments; i++) { result = copy_from_user(&in, &segments[i], sizeof(in)); if (result) - return -EFAULT; + goto fail; - out.buf = compat_ptr(in.buf); - out.bufsz = in.bufsz; - out.mem = in.mem; - out.memsz = in.memsz; - - result = copy_to_user(&ksegments[i], &out, sizeof(out)); - if (result) - return -EFAULT; + ksegments[i].buf = compat_ptr(in.buf); + ksegments[i].bufsz = in.bufsz; + ksegments[i].mem = in.mem; + ksegments[i].memsz = in.memsz; } result = do_kexec_load(entry, nr_segments, ksegments, flags); +fail: + kfree(ksegments); return result; } #endif