diff options
| author | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2016-04-26 23:42:25 +0200 |
|---|---|---|
| committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2016-04-26 23:42:25 +0200 |
| commit | f2d22b3bab4de4b20c857bf6f0191fb6c000fd14 (patch) | |
| tree | 9b01cc0483fcfc1233a80497b3620116dca31171 | |
| parent | f4d6b646a1aa6f8e489dd3eeae1a188de0b2a070 (diff) | |
libdiskfs: Reject LFS seeks and read/writes
vm_offset_t (used by pager_memcpy) is not 64bit-ready yet. Reject requests
which go further than this.
* libdiskfs/io-seek.c (diskfs_S_io_seek): Return EFBIG when requested offset
is beyond limits of vm_offset_t.
* libdiskfs/rdwr-internal.c (_diskfs_rdwr_internal): Return EFBIG when
request goes beyond limits of vm_offset_t.
| -rw-r--r-- | libdiskfs/io-seek.c | 8 | ||||
| -rw-r--r-- | libdiskfs/rdwr-internal.c | 7 |
2 files changed, 14 insertions, 1 deletions
diff --git a/libdiskfs/io-seek.c b/libdiskfs/io-seek.c index 9e3ff093..0018a712 100644 --- a/libdiskfs/io-seek.c +++ b/libdiskfs/io-seek.c @@ -46,6 +46,14 @@ diskfs_S_io_seek (struct protid *cred, offset += np->dn_stat.st_size; case SEEK_SET: check: + /* pager_memcpy inherently uses vm_offset_t, which may be smaller than + off_t. */ + if (sizeof(off_t) > sizeof(vm_offset_t) && + offset > ((off_t) 1) << (sizeof(vm_offset_t) * 8)) + { + err = EFBIG; + break; + } if (offset >= 0) { *newoffset = cred->po->filepointer = offset; diff --git a/libdiskfs/rdwr-internal.c b/libdiskfs/rdwr-internal.c index 18a4ae1e..0d405517 100644 --- a/libdiskfs/rdwr-internal.c +++ b/libdiskfs/rdwr-internal.c @@ -58,7 +58,12 @@ _diskfs_rdwr_internal (struct node *np, if (memobj == MACH_PORT_NULL) return errno; - err = pager_memcpy (diskfs_get_filemap_pager_struct (np), memobj, + /* pager_memcpy inherently uses vm_offset_t, which may be smaller than off_t. */ + if (sizeof(off_t) > sizeof(vm_offset_t) && + offset + *amt > ((off_t) 1) << (sizeof(vm_offset_t) * 8)) + err = EFBIG; + else + err = pager_memcpy (diskfs_get_filemap_pager_struct (np), memobj, offset, data, amt, prot); if (!diskfs_check_readonly () && !notime) |