linux-stable/fs
Linus Torvalds 27f8c4402c qnx4: work around gcc false positive warning bug
commit d5f6545934 upstream.

In commit b7213ffa0e ("qnx4: avoid stringop-overread errors") I tried
to teach gcc about how the directory entry structure can be two
different things depending on a status flag.  It made the code clearer,
and it seemed to make gcc happy.

However, Arnd points to a gcc bug, where despite using two different
members of a union, gcc then gets confused, and uses the size of one of
the members to decide if a string overrun happens.  And not necessarily
the rigth one.

End result: with some configurations, gcc-11 will still complain about
the source buffer size being overread:

  fs/qnx4/dir.c: In function 'qnx4_readdir':
  fs/qnx4/dir.c:76:32: error: 'strnlen' specified bound [16, 48] exceeds source size 1 [-Werror=stringop-overread]
     76 |                         size = strnlen(name, size);
        |                                ^~~~~~~~~~~~~~~~~~~
  fs/qnx4/dir.c:26:22: note: source object declared here
     26 |                 char de_name;
        |                      ^~~~~~~

because gcc will get confused about which union member entry is actually
getting accessed, even when the source code is very clear about it.  Gcc
internally will have combined two "redundant" pointers (pointing to
different union elements that are at the same offset), and takes the
size checking from one or the other - not necessarily the right one.

This is clearly a gcc bug, but we can work around it fairly easily.  The
biggest thing here is the big honking comment about why we do what we
do.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578#c6
Reported-and-tested-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-30 10:09:26 +02:00
..
9p 9P: Cast to loff_t before multiplying 2020-11-05 11:43:34 +01:00
adfs
affs fs/affs: release old buffer head on error path 2021-03-04 10:26:48 +01:00
afs afs: Fix incorrect triggering of sillyrename on 3rd-party invalidation 2021-09-30 10:09:22 +02:00
autofs autofs: fix a leak in autofs_expire_indirect() 2019-10-25 00:03:11 -04:00
befs
bfs bfs: don't use WARNING: string when it's just info. 2021-01-06 14:48:39 +01:00
btrfs btrfs: prevent __btrfs_dump_space_info() to underflow its free space 2021-09-30 10:09:22 +02:00
cachefiles cachefiles: Handle readpage error correctly 2020-11-05 11:43:36 +01:00
ceph ceph: lockdep annotations for try_nonblocking_invalidate 2021-09-26 14:07:11 +02:00
cifs cifs: fix a sign extension bug 2021-09-30 10:09:24 +02:00
coda y2038: add inode timestamp clamping 2019-09-19 09:42:37 -07:00
configfs configfs: fix memleak in configfs_release_bin_file 2021-07-14 16:53:46 +02:00
cramfs cramfs: fix usage on non-MTD device 2019-11-23 21:44:49 -05:00
crypto fscrypt: add fscrypt_symlink_getattr() for computing st_size 2021-09-12 08:56:38 +02:00
debugfs debugfs: Return error during {full/open}_proxy_open() on rmmod 2021-09-15 09:47:33 +02:00
devpts
dlm fs: dlm: fix memory leak when fenced 2021-07-14 16:53:17 +02:00
ecryptfs Revert "ecryptfs: replace BUG_ON with error handling code" 2021-05-26 12:05:19 +02:00
efivarfs efivarfs: revert "fix memory leak in efivarfs_create()" 2020-12-02 08:49:53 +01:00
efs
erofs erofs: add unsupported inode i_format check 2021-05-11 14:04:02 +02:00
exportfs exportfs_decode_fh(): negative pinned may become positive without the parent locked 2019-11-10 11:56:05 -05:00
ext2 ext2: don't update mtime on COW faults 2020-09-09 19:12:30 +02:00
ext4 ext4: report correct st_size for encrypted symlinks 2021-09-12 08:56:38 +02:00
f2fs f2fs: fix to unmap pages from userspace process in punch_hole() 2021-09-22 12:26:26 +02:00
fat fat: don't allow to mount if the FAT length == 0 2020-06-17 16:40:36 +02:00
freevxfs
fscache fscache: Fix cookie key hashing 2021-09-22 12:26:25 +02:00
fuse fuse: fix use after free in fuse_read_interrupt() 2021-09-22 12:26:43 +02:00
gfs2 gfs2: Don't call dlm after protocol is unmounted 2021-09-22 12:26:33 +02:00
hfs hfs: add lock nesting notation to hfs_find_init 2021-07-31 08:19:38 +02:00
hfsplus hfsplus: prevent corruption in shrinking truncate 2021-05-19 10:08:29 +02:00
hostfs hostfs: fix memory handling in follow_link() 2021-04-14 08:24:14 +02:00
hpfs
hugetlbfs hugetlbfs: fix mount mode command line processing 2021-07-28 13:31:01 +02:00
iomap mm/swap: consider max pages in iomap_swapfile_add_extent 2021-09-15 09:47:35 +02:00
isofs isofs: joliet: Fix iocharset=utf8 mount option 2021-09-15 09:47:27 +02:00
jbd2 jbd2: fix up sparse warnings in checkpoint code 2020-11-18 19:20:30 +01:00
jffs2 jffs2: check the validity of dstlen in jffs2_zlib_compress() 2021-05-11 14:04:16 +02:00
jfs fs/jfs: Fix missing error code in lmLogInit() 2021-07-20 16:10:42 +02:00
kernfs kernfs: do not call fsnotify() with name without a parent 2020-08-19 08:16:12 +02:00
lockd lockd: lockd server-side shouldn't set fl_ops 2021-09-22 12:26:34 +02:00
minix fs/minix: remove expected error message in block_to_path() 2020-08-21 13:05:37 +02:00
nfs NFSv4/pNFS: Don't call _nfs4_pnfs_v3_ds_connect multiple times 2021-07-20 16:10:50 +02:00
nfs_common nfs_common: need lock during iterate through the list 2020-12-30 11:51:22 +01:00
nfsd nfsd4: Fix forced-expiry locking 2021-09-15 09:47:35 +02:00
nilfs2 nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group 2021-09-26 14:07:13 +02:00
nls
notify fanotify: fix ignore mask logic for events on child and on dir 2020-06-17 16:40:24 +02:00
ntfs ntfs: fix validity check for file name attribute 2021-07-14 16:53:01 +02:00
ocfs2 ocfs2: drop acl cache for directories too 2021-09-30 10:09:20 +02:00
omfs
openpromfs
orangefs orangefs: fix orangefs df output. 2021-07-20 16:10:48 +02:00
overlayfs ovl: fix BUG_ON() in may_delete() when called from ovl_cleanup() 2021-09-22 12:26:37 +02:00
proc mm, oom: make the calculation of oom badness more accurate 2021-09-03 10:08:12 +02:00
pstore pstore: Fix typo in compression option name 2021-03-04 10:26:45 +01:00
qnx4 qnx4: work around gcc false positive warning bug 2021-09-30 10:09:26 +02:00
qnx6
quota quota: Fix memory leak when handling corrupted quota file 2021-03-04 10:26:26 +01:00
ramfs ramfs: fix nommu mmap with gaps in the page cache 2020-10-29 09:57:53 +01:00
reiserfs reiserfs: check directory items on read from disk 2021-08-12 13:21:05 +02:00
romfs romfs: fix uninitialized memory leak in romfs_dev_read() 2020-08-26 10:40:51 +02:00
squashfs squashfs: fix divide error in calculate_skip() 2021-05-19 10:08:29 +02:00
sysfs sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output 2021-03-07 12:20:48 +01:00
sysv
tracefs tracing: Do not create tracefs files if tracefs lockdown is in effect 2019-10-12 20:49:07 -04:00
ubifs ubifs: report correct st_size for encrypted symlinks 2021-09-12 08:56:39 +02:00
udf udf_get_extendedattr() had no boundary checks. 2021-09-15 09:47:28 +02:00
ufs fs/ufs: avoid potential u32 multiplication overflow 2020-08-21 13:05:37 +02:00
unicode unicode: make array 'token' static const, makes object smaller 2019-09-17 11:48:24 -04:00
verity
xfs xfs: Fix assert failure in xfs_setattr_size() 2021-03-07 12:20:42 +01:00
aio.c aio: fix async fsync creds 2020-06-17 16:40:24 +02:00
anon_inodes.c
attr.c utimes: Clamp the timestamps in notify_change() 2020-02-11 04:35:12 -08:00
bad_inode.c
binfmt_aout.c
binfmt_elf.c fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info() 2020-06-03 08:21:27 +02:00
binfmt_elf_fdpic.c
binfmt_em86.c
binfmt_flat.c binfmt_flat: revert "binfmt_flat: don't offset the data start" 2020-09-03 11:26:39 +02:00
binfmt_misc.c binfmt_misc: fix possible deadlock in bm_register_write 2021-03-17 17:03:57 +01:00
binfmt_script.c
block_dev.c block: reexpand iov_iter after read/write 2021-05-22 11:38:29 +02:00
buffer.c fs: Don't invalidate page buffers in block_write_full_page() 2020-11-05 11:43:24 +01:00
char_dev.c chardev: Avoid potential use-after-free in 'chrdev_open()' 2020-01-14 20:08:18 +01:00
compat.c
compat_binfmt_elf.c
compat_ioctl.c fix compat handling of FICLONERANGE, FIDEDUPERANGE and FS_IOC_FIEMAP 2020-01-09 10:20:05 +01:00
coredump.c coredump: fix core_pattern parse error 2020-12-11 13:23:30 +01:00
d_path.c fs: fix NULL dereference due to data race in prepend_path() 2020-10-29 09:57:45 +01:00
dax.c dax: fix ENOMEM handling in grab_mapping_entry() 2021-07-14 16:53:25 +02:00
dcache.c fix dget_parent() fastpath race 2020-10-01 13:17:19 +02:00
dcookies.c
direct-io.c fs: direct-io: fix missing sdio->boundary 2021-04-14 08:24:11 +02:00
drop_caches.c fs: avoid softlockups in s_inodes iterators 2020-01-12 12:21:37 +01:00
eventfd.c eventfd: track eventfd_signal() recursion depth 2020-02-11 04:35:37 -08:00
eventpoll.c ep_create_wakeup_source(): dentry name can change under you... 2020-10-07 08:01:31 +02:00
exec.c exec: Transform exec_update_mutex into a rw_semaphore 2021-01-09 13:44:55 +01:00
fcntl.c fcntl: fix potential deadlock for &fasync_struct.fa_lock 2021-09-15 09:47:28 +02:00
fhandle.c
file.c fix multiplication overflow in copy_fdtable() 2020-05-27 17:46:12 +02:00
file_table.c
filesystems.c fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() 2020-04-17 10:50:21 +02:00
fs-writeback.c writeback: fix obtain a reference to a freeing memcg css 2021-07-14 16:53:35 +02:00
fs_context.c
fs_parser.c vfs: Make fs_parse() handle fs_param_is_fd-type params better 2019-09-12 21:06:14 -04:00
fs_pin.c
fs_struct.c
fs_types.c
fsopen.c
inode.c futex: Fix inode life-time issue 2020-03-25 08:25:58 +01:00
internal.h cgroup1: fix leaked context root causing sporadic NULL deref in LTP 2021-07-31 08:19:37 +02:00
io_uring.c io_uring: Fix current->fs handling in io_sq_wq_submit_work() 2021-01-30 13:54:10 +01:00
ioctl.c compat_ioctl: add compat_ptr_ioctl() 2019-12-17 19:55:30 +01:00
Kconfig fs-verity for 5.4 2019-09-18 16:59:14 -07:00
Kconfig.binfmt
libfs.c libfs: fix error cast of negative value in simple_attr_write() 2020-11-24 13:29:19 +01:00
locks.c locks: reinstate locks_delete_block optimization 2020-03-25 08:25:41 +01:00
Makefile fs-verity for 5.4 2019-09-18 16:59:14 -07:00
mbcache.c
mount.h
mpage.c fs: move guard_bio_eod() after bio_set_op_attrs 2020-01-17 19:48:21 +01:00
namei.c namei: only return -ECHILD from follow_dotdot_rcu() 2020-03-05 16:43:48 +01:00
namespace.c fs: warn about impending deprecation of mandatory locks 2021-08-26 08:36:22 -04:00
no-block.c
nsfs.c
open.c cifs_atomic_open(): fix double-put on late allocation failure 2020-03-18 07:17:51 +01:00
pipe.c pipe: increase minimum default pipe size to 2 pages 2021-08-12 13:21:02 +02:00
pnode.c propagate_one(): mnt_set_mountpoint() needs mount_lock 2020-05-02 08:48:44 +02:00
pnode.h mount: fix mounting of detached mounts onto targets that reside on shared mounts 2021-03-17 17:03:33 +01:00
posix_acl.c
proc_namespace.c
read_write.c fs: allow deduplication of eof block into the end of the destination file 2020-02-11 04:35:23 -08:00
readdir.c readdir: make sure to verify directory entry for legacy interfaces too 2021-04-21 12:56:16 +02:00
select.c kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data() 2021-03-24 11:26:44 +01:00
seq_file.c seq_file: disallow extremely large seq buffer allocations 2021-07-20 16:10:54 +02:00
signalfd.c fs/signalfd.c: fix inconsistent return codes for signalfd4 2020-08-26 10:40:58 +02:00
splice.c splice: only read in as much information as there is pipe buffer space 2019-12-17 19:56:52 +01:00
stack.c
stat.c
statfs.c vfs: Fix EOVERFLOW testing in put_compat_statfs64 2019-10-03 14:21:35 -07:00
super.c vfs: remove lockdep bogosity in __sb_start_write 2020-11-24 13:29:01 +01:00
sync.c
timerfd.c
userfaultfd.c userfaultfd: prevent concurrent API initialization 2021-09-22 12:26:26 +02:00
utimes.c utimes: Clamp the timestamps in notify_change() 2020-02-11 04:35:12 -08:00
xattr.c xattr: break delegations in {set,remove}xattr 2020-08-11 15:33:39 +02:00