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2020-01-04filldir[64]: remove WARN_ON_ONCE() for bad directory entriesLinus Torvalds
commit b9959c7a347d6adbb558fba7e36e9fef3cba3b07 upstream. This was always meant to be a temporary thing, just for testing and to see if it actually ever triggered. The only thing that reported it was syzbot doing disk image fuzzing, and then that warning is expected. So let's just remove it before -rc4, because the extra sanity testing should probably go to -stable, but we don't want the warning to do so. Reported-by: syzbot+3031f712c7ad5dd4d926@syzkaller.appspotmail.com Fixes: 8a23eb804ca4 ("Make filldir[64]() verify the directory entry filename is valid") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Siddharth Chandrasekaran <csiddharth@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04Make filldir[64]() verify the directory entry filename is validLinus Torvalds
commit 8a23eb804ca4f2be909e372cf5a9e7b30ae476cd upstream. This has been discussed several times, and now filesystem people are talking about doing it individually at the filesystem layer, so head that off at the pass and just do it in getdents{64}(). This is partially based on a patch by Jann Horn, but checks for NUL bytes as well, and somewhat simplified. There's also commentary about how it might be better if invalid names due to filesystem corruption don't cause an immediate failure, but only an error at the end of the readdir(), so that people can still see the filenames that are ok. There's also been discussion about just how much POSIX strictly speaking requires this since it's about filesystem corruption. It's really more "protect user space from bad behavior" as pointed out by Jann. But since Eric Biederman looked up the POSIX wording, here it is for context: "From readdir: The readdir() function shall return a pointer to a structure representing the directory entry at the current position in the directory stream specified by the argument dirp, and position the directory stream at the next entry. It shall return a null pointer upon reaching the end of the directory stream. The structure dirent defined in the <dirent.h> header describes a directory entry. From definitions: 3.129 Directory Entry (or Link) An object that associates a filename with a file. Several directory entries can associate names with the same file. ... 3.169 Filename A name consisting of 1 to {NAME_MAX} bytes used to name a file. The characters composing the name may be selected from the set of all character values excluding the slash character and the null byte. The filenames dot and dot-dot have special meaning. A filename is sometimes referred to as a 'pathname component'." Note that I didn't bother adding the checks to any legacy interfaces that nobody uses. Also note that if this ends up being noticeable as a performance regression, we can fix that to do a much more optimized model that checks for both NUL and '/' at the same time one word at a time. We haven't really tended to optimize 'memchr()', and it only checks for one pattern at a time anyway, and we really _should_ check for NUL too (but see the comment about "soft errors" in the code about why it currently only checks for '/') See the CONFIG_DCACHE_WORD_ACCESS case of hash_name() for how the name lookup code looks for pathname terminating characters in parallel. Link: https://lore.kernel.org/lkml/20190118161440.220134-2-jannh@google.com/ Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jann Horn <jannh@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Siddharth Chandrasekaran <csiddharth@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-26restore killability of old mutex_lock_killable(&inode->i_mutex) usersAl Viro
The ones that are taking it exclusive, that is... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-24Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Fix a number of bugs, most notably a potential stale data exposure after a crash and a potential BUG_ON crash if a file has the data journalling flag enabled while it has dirty delayed allocation blocks that haven't been written yet. Also fix a potential crash in the new project quota code and a maliciously corrupted file system. In addition, fix some DAX-specific bugs, including when there is a transient ENOSPC situation and races between writes via direct I/O and an mmap'ed segment that could lead to lost I/O. Finally the usual set of miscellaneous cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits) ext4: pre-zero allocated blocks for DAX IO ext4: refactor direct IO code ext4: fix race in transient ENOSPC detection ext4: handle transient ENOSPC properly for DAX dax: call get_blocks() with create == 1 for write faults to unwritten extents ext4: remove unmeetable inconsisteny check from ext4_find_extent() jbd2: remove excess descriptions for handle_s ext4: remove unnecessary bio get/put ext4: silence UBSAN in ext4_mb_init() ext4: address UBSAN warning in mb_find_order_for_block() ext4: fix oops on corrupted filesystem ext4: fix check of dqget() return value in ext4_ioctl_setproject() ext4: clean up error handling when orphan list is corrupted ext4: fix hang when processing corrupted orphaned inode list ext4: remove trailing \n from ext4_warning/ext4_error calls ext4: fix races between changing inode journal mode and ext4_writepages ext4: handle unwritten or delalloc buffers before enabling data journaling ext4: fix jbd2 handle extension in ext4_ext_truncate_extend_restart() ext4: do not ask jbd2 to write data for delalloc buffers jbd2: add support for avoiding data writes during transaction commits ...
2016-05-02introduce a parallel variant of ->iterate()Al Viro
New method: ->iterate_shared(). Same arguments as in ->iterate(), called with the directory locked only shared. Once all filesystems switch, the old one will be gone. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02give readdir(2)/getdents(2)/etc. uniform exclusion with lseek()Al Viro
same as read() on regular files has, and for the same reason. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02parallel lookups: actual switch to rwsemAl Viro
ta-da! The main issue is the lack of down_write_killable(), so the places like readdir.c switched to plain inode_lock(); once killable variants of rwsem primitives appear, that'll be dealt with. lockdep side also might need more work Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-23ext4: allow readdir()'s of large empty directories to be interruptedTheodore Ts'o
If a directory has a large number of empty blocks, iterating over all of them can take a long time, leading to scheduler warnings and users getting irritated when they can't kill a process in the middle of one of these long-running readdir operations. Fix this by adding checks to ext4_readdir() and ext4_htree_fill_tree(). This was reverted earlier due to a typo in the original commit where I experimented with using signal_pending() instead of fatal_signal_pending(). The test was in the wrong place if we were going to return signal_pending() since we would end up returning duplicant entries. See 9f2394c9be47 for a more detailed explanation. Added fix as suggested by Linus to check for signal_pending() in in the filldir() functions. Reported-by: Benjamin LaHaise <bcrl@kvack.org> Google-Bug-Id: 27880676 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-01-22wrappers for ->i_mutex accessAl Viro
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-31vfs: make first argument of dir_context.actor typedMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-06-04fanotify: create FAN_ACCESS event for readdirHeinrich Schuchardt
Before the patch, read creates FAN_ACCESS_PERM and FAN_ACCESS events, readdir creates only FAN_ACCESS_PERM events. This is inconsistent. After the patch, readdir creates FAN_ACCESS_PERM and FAN_ACCESS events. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-24file->f_op is never NULL...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29[readdir] constify ->actorAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29[readdir] ->readdir() is goneAl Viro
everything's converted to ->iterate() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29[readdir] introduce ->iterate(), ctx->pos, dir_emit()Al Viro
New method - ->iterate(file, ctx). That's the replacement for ->readdir(); it takes callback from ctx->actor, uses ctx->pos instead of file->f_pos and calls dir_emit(ctx, ...) instead of filldir(data, ...). It does *not* update file->f_pos (or look at it, for that matter); iterate_dir() does the update. Note that dir_emit() takes the offset from ctx->pos (and eventually filldir_t will lose that argument). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29[readdir] introduce iterate_dir() and dir_contextAl Viro
iterate_dir(): new helper, replacing vfs_readdir(). struct dir_context: contains the readdir callback (and will get more stuff in it), embedded into whatever data that callback wants to deal with; eventually, we'll be passing it to ->readdir() replacement instead of (data,filldir) pair. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26switch simple cases of fget_light to fdgetAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29switch readdir/getdents to fget_light/fput_lightAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-02-28fs: reduce the use of module.h wherever possiblePaul Gortmaker
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2010-08-09vfs: fix warning: 'dirent' is used uninitialized in this functionKevin Winchester
Using: gcc (GCC) 4.5.0 20100610 (prerelease) The following warnings appear: fs/readdir.c: In function `filldir64': fs/readdir.c:240:15: warning: `dirent' is used uninitialized in this function fs/readdir.c: In function `filldir': fs/readdir.c:155:15: warning: `dirent' is used uninitialized in this function fs/compat.c: In function `compat_filldir64': fs/compat.c:1071:11: warning: `dirent' is used uninitialized in this function fs/compat.c: In function `compat_filldir': fs/compat.c:984:15: warning: `dirent' is used uninitialized in this function The warnings are related to the use of the NAME_OFFSET() macro. Luckily, it appears as though the standard offsetof() macro is what is being implemented by NAME_OFFSET(), thus we can fix the warning and use a more standard code construct at the same time. Signed-off-by: Kevin Winchester <kjwinchester@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-14[CVE-2009-0029] System call wrappers part 32Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14[CVE-2009-0029] System call wrappers part 21Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14[CVE-2009-0029] Rename old_readdir to sys_old_readdirHeiko Carstens
This way it matches the generic system call name convention. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-10-23[PATCH] prepare vfs_readdir() callers to returning filldir resultAl Viro
It's not the final state, but it allows moving ->readdir() instances to passing filldir return value to caller of vfs_readdir(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-08-25[PATCH] fix regular readdir() and friendsAl Viro
Handling of -EOVERFLOW. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-12-06Use mutex_lock_killable in vfs_readdirLiam R. Howlett
Signed-off-by: Liam R. Howlett <howlett@gmail.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2007-05-08ROUND_UP macro cleanup in fs/(select|compat|readdir).cMilind Arun Choudhary
ROUND_UP macro cleanup use,ALIGN or DIV_ROUND_UP where ever appropriate. Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap
Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-08[PATCH] VFS: change struct file to use struct pathJosef "Jeff" Sipek
This patch changes struct file to use struct path instead of having independent pointers to struct dentry and struct vfsmount, and converts all users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}. Additionally, it adds two #define's to make the transition easier for users of the f_dentry and f_vfsmnt. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03[PATCH] VFS: Make filldir_t and struct kstat deal in 64-bit inode numbersDavid Howells
These patches make the kernel pass 64-bit inode numbers internally when communicating to userspace, even on a 32-bit system. They are required because some filesystems have intrinsic 64-bit inode numbers: NFS3+ and XFS for example. The 64-bit inode numbers are then propagated to userspace automatically where the arch supports it. Problems have been seen with userspace (eg: ld.so) using the 64-bit inode number returned by stat64() or getdents64() to differentiate files, and failing because the 64-bit inode number space was compressed to 32-bits, and so overlaps occur. This patch: Make filldir_t take a 64-bit inode number and struct kstat carry a 64-bit inode number so that 64-bit inode numbers can be passed back to userspace. The stat functions then returns the full 64-bit inode number where available and where possible. If it is not possible to represent the inode number supplied by the filesystem in the field provided by userspace, then error EOVERFLOW will be issued. Similarly, the getdents/readdir functions now pass the full 64-bit inode number to userspace where possible, returning EOVERFLOW instead when a directory entry is encountered that can't be properly represented. Note that this means that some inodes will not be stat'able on a 32-bit system with old libraries where they were before - but it does mean that there will be no ambiguity over what a 32-bit inode number refers to. Note similarly that directory scans may be cut short with an error on a 32-bit system with old libraries where the scan would work before for the same reasons. It is judged unlikely that this situation will occur because modern glibc uses 64-bit capable versions of stat and getdents class functions exclusively, and that older systems are unlikely to encounter unrepresentable inode numbers anyway. [akpm: alpha build fix] Signed-off-by: David Howells <dhowells@redhat.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-09[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_semJes Sorensen
This patch converts the inode semaphore to a mutex. I have tested it on XFS and compiled as much as one can consider on an ia64. Anyway your luck with it might be different. Modified-by: Ingo Molnar <mingo@elte.hu> (finished the conversion) Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!