diff options
Diffstat (limited to 'fs/statfs.c')
| -rw-r--r-- | fs/statfs.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/fs/statfs.c b/fs/statfs.c index 13ae259d4879..4e4623c7a126 100644 --- a/fs/statfs.c +++ b/fs/statfs.c @@ -7,6 +7,7 @@ #include <linux/statfs.h> #include <linux/security.h> #include <linux/uaccess.h> +#include <linux/compat.h> #include "internal.h" static int flags_by_mnt(int mnt_flags) @@ -239,3 +240,142 @@ SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf) return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0; } + +#ifdef CONFIG_COMPAT +static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf) +{ + if (sizeof ubuf->f_blocks == 4) { + if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail | + kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL) + return -EOVERFLOW; + /* f_files and f_ffree may be -1; it's okay + * to stuff that into 32 bits */ + if (kbuf->f_files != 0xffffffffffffffffULL + && (kbuf->f_files & 0xffffffff00000000ULL)) + return -EOVERFLOW; + if (kbuf->f_ffree != 0xffffffffffffffffULL + && (kbuf->f_ffree & 0xffffffff00000000ULL)) + return -EOVERFLOW; + } + if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) || + __put_user(kbuf->f_type, &ubuf->f_type) || + __put_user(kbuf->f_bsize, &ubuf->f_bsize) || + __put_user(kbuf->f_blocks, &ubuf->f_blocks) || + __put_user(kbuf->f_bfree, &ubuf->f_bfree) || + __put_user(kbuf->f_bavail, &ubuf->f_bavail) || + __put_user(kbuf->f_files, &ubuf->f_files) || + __put_user(kbuf->f_ffree, &ubuf->f_ffree) || + __put_user(kbuf->f_namelen, &ubuf->f_namelen) || + __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) || + __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) || + __put_user(kbuf->f_frsize, &ubuf->f_frsize) || + __put_user(kbuf->f_flags, &ubuf->f_flags) || + __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare))) + return -EFAULT; + return 0; +} + +/* + * The following statfs calls are copies of code from fs/statfs.c and + * should be checked against those from time to time + */ +COMPAT_SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct compat_statfs __user *, buf) +{ + struct kstatfs tmp; + int error = user_statfs(pathname, &tmp); + if (!error) + error = put_compat_statfs(buf, &tmp); + return error; +} + +COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct compat_statfs __user *, buf) +{ + struct kstatfs tmp; + int error = fd_statfs(fd, &tmp); + if (!error) + error = put_compat_statfs(buf, &tmp); + return error; +} + +static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf) +{ + if (sizeof(ubuf->f_bsize) == 4) { + if ((kbuf->f_type | kbuf->f_bsize | kbuf->f_namelen | + kbuf->f_frsize | kbuf->f_flags) & 0xffffffff00000000ULL) + return -EOVERFLOW; + /* f_files and f_ffree may be -1; it's okay + * to stuff that into 32 bits */ + if (kbuf->f_files != 0xffffffffffffffffULL + && (kbuf->f_files & 0xffffffff00000000ULL)) + return -EOVERFLOW; + if (kbuf->f_ffree != 0xffffffffffffffffULL + && (kbuf->f_ffree & 0xffffffff00000000ULL)) + return -EOVERFLOW; + } + if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) || + __put_user(kbuf->f_type, &ubuf->f_type) || + __put_user(kbuf->f_bsize, &ubuf->f_bsize) || + __put_user(kbuf->f_blocks, &ubuf->f_blocks) || + __put_user(kbuf->f_bfree, &ubuf->f_bfree) || + __put_user(kbuf->f_bavail, &ubuf->f_bavail) || + __put_user(kbuf->f_files, &ubuf->f_files) || + __put_user(kbuf->f_ffree, &ubuf->f_ffree) || + __put_user(kbuf->f_namelen, &ubuf->f_namelen) || + __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) || + __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) || + __put_user(kbuf->f_frsize, &ubuf->f_frsize) || + __put_user(kbuf->f_flags, &ubuf->f_flags) || + __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare))) + return -EFAULT; + return 0; +} + +COMPAT_SYSCALL_DEFINE3(statfs64, const char __user *, pathname, compat_size_t, sz, struct compat_statfs64 __user *, buf) +{ + struct kstatfs tmp; + int error; + + if (sz != sizeof(*buf)) + return -EINVAL; + + error = user_statfs(pathname, &tmp); + if (!error) + error = put_compat_statfs64(buf, &tmp); + return error; +} + +COMPAT_SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, compat_size_t, sz, struct compat_statfs64 __user *, buf) +{ + struct kstatfs tmp; + int error; + + if (sz != sizeof(*buf)) + return -EINVAL; + + error = fd_statfs(fd, &tmp); + if (!error) + error = put_compat_statfs64(buf, &tmp); + return error; +} + +/* + * This is a copy of sys_ustat, just dealing with a structure layout. + * Given how simple this syscall is that apporach is more maintainable + * than the various conversion hacks. + */ +COMPAT_SYSCALL_DEFINE2(ustat, unsigned, dev, struct compat_ustat __user *, u) +{ + struct compat_ustat tmp; + struct kstatfs sbuf; + int err = vfs_ustat(new_decode_dev(dev), &sbuf); + if (err) + return err; + + memset(&tmp, 0, sizeof(struct compat_ustat)); + tmp.f_tfree = sbuf.f_bfree; + tmp.f_tinode = sbuf.f_ffree; + if (copy_to_user(u, &tmp, sizeof(struct compat_ustat))) + return -EFAULT; + return 0; +} +#endif |