kernel/git/stable/linux.git/fs/fuse/dir.c, branch linux-4.4.y

fuse: verify attributes

2019-12-21T09:34:49+00:00

commit eb59bd17d2fa6e5e84fba61a5ebdea984222e6d5 upstream. If a filesystem returns negative inode sizes, future reads on the file were causing the cpu to spin on truncate_pagecache. Create a helper to validate the attributes. This now does two things: - check the file mode - check if the file size fits in i_size without overflowing Reported-by: Arijit Banerjee Fixes: d8a5ba45457e ("[PATCH] FUSE - core") Cc: # v2.6.14 Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: verify nlink

2019-12-21T09:34:48+00:00

commit c634da718db9b2fac201df2ae1b1b095344ce5eb upstream. When adding a new hard link, make sure that i_nlink doesn't overflow. Fixes: ac45d61357e8 ("fuse: fix nlink after unlink") Cc: # v3.4 Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: flush dirty data/metadata before non-truncate setattr

2019-11-06T11:09:18+00:00

commit b24e7598db62386a95a3c8b9c75630c5d56fe077 upstream. If writeback cache is enabled, then writes might get reordered with chmod/chown/utimes. The problem with this is that performing the write in the fuse daemon might itself change some of these attributes. In such case the following sequence of operations will result in file ending up with the wrong mode, for example: int fd = open ("suid", O_WRONLY|O_CREAT|O_EXCL); write (fd, "1", 1); fchown (fd, 0, 0); fchmod (fd, 04755); close (fd); This patch fixes this by flushing pending writes before performing chown/chmod/utimes. Reported-by: Giuseppe Scrivano Tested-by: Giuseppe Scrivano Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Cc: # v3.15+ Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: atomic_o_trunc should truncate pagecache

2018-07-03T09:21:28+00:00

commit df0e91d488276086bc07da2e389986cae0048c37 upstream. Fuse has an "atomic_o_trunc" mode, where userspace filesystem uses the O_TRUNC flag in the OPEN request to truncate the file atomically with the open. In this mode there's no need to send a SETATTR request to userspace after the open, so fuse_do_setattr() checks this mode and returns. But this misses the important step of truncating the pagecache. Add the missing parts of truncation to the ATTR_OPEN branch. Reported-by: Chad Austin Fixes: 6ff958edbf39 ("fuse: add atomic open+truncate support") Signed-off-by: Miklos Szeredi Cc: Signed-off-by: Greg Kroah-Hartman

fuse: fix READDIRPLUS skipping an entry

2017-11-02T08:40:49+00:00

commit c6cdd51404b7ac12dd95173ddfc548c59ecf037f upstream. Marios Titas running a Haskell program noticed a problem with fuse's readdirplus: when it is interrupted by a signal, it skips one directory entry. The reason is that fuse erronously updates ctx->pos after a failed dir_emit(). The issue originates from the patch adding readdirplus support. Reported-by: Jakob Unterwurzacher Tested-by: Marios Titas Signed-off-by: Miklos Szeredi Fixes: 0b05b18381ee ("fuse: implement NFS-like readdirplus support") Signed-off-by: Greg Kroah-Hartman

fuse: fix killing s[ug]id in setattr

2016-10-22T10:26:55+00:00

commit a09f99eddef44035ec764075a37bace8181bec38 upstream. Fuse allowed VFS to set mode in setattr in order to clear suid/sgid on chown and truncate, and (since writeback_cache) write. The problem with this is that it'll potentially restore a stale mode. The poper fix would be to let the filesystems do the suid/sgid clearing on the relevant operations. Possibly some are already doing it but there's no way we can detect this. So fix this by refreshing and recalculating the mode. Do this only if ATTR_KILL_S[UG]ID is set to not destroy performance for writes. This is still racy but the size of the window is reduced. Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: invalidate dir dentry after chmod

2016-10-22T10:26:55+00:00

commit 5e2b8828ff3d79aca8c3a1730652758753205b61 upstream. Without "default_permissions" the userspace filesystem's lookup operation needs to perform the check for search permission on the directory. If directory does not allow search for everyone (this is quite rare) then userspace filesystem has to set entry timeout to zero to make sure permissions are always performed. Changing the mode bits of the directory should also invalidate the (previously cached) dentry to make sure the next lookup will have a chance of updating the timeout, if needed. Reported-by: Jean-Pierre André Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: listxattr: verify xattr list

2016-10-22T10:26:55+00:00

commit cb3ae6d25a5471be62bfe6ac1fccc0e91edeaba0 upstream. Make sure userspace filesystem is returning a well formed list of xattr names (zero or more nonzero length, null terminated strings). [Michael Theall: only verify in the nonzero size case] Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

new helper: free_page_put_link()

2015-05-11T12:13:13+00:00

similar to kfree_put_link() Signed-off-by: Al Viro

switch ->put_link() from dentry to inode

2015-05-11T12:13:12+00:00

only one instance looks at that argument at all; that sole exception wants inode rather than dentry. Signed-off-by: Al Viro