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path: root/fs/ufs/super.c
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2023-10-28exportfs: make ->encode_fh() a mandatory method for NFS exportAmir Goldstein
Rename the default helper for encoding FILEID_INO32_GEN* file handles to generic_encode_ino32_fh() and convert the filesystems that used the default implementation to use the generic helper explicitly. After this change, exportfs_encode_inode_fh() no longer has a default implementation to encode FILEID_INO32_GEN* file handles. This is a step towards allowing filesystems to encode non-decodeable file handles for fanotify without having to implement any export_operations. Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jeff Layton <jlayton@kernel.org> Acked-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20231023180801.2953446-3-amir73il@gmail.com Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2022-03-22fs: allocate inode by using alloc_inode_sb()Muchun Song
The inode allocation is supposed to use alloc_inode_sb(), so convert kmem_cache_alloc() of all filesystems to alloc_inode_sb(). Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Theodore Ts'o <tytso@mit.edu> [ext4] Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Alex Shi <alexs@kernel.org> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Chao Yu <chao@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Fam Zheng <fam.zheng@bytedance.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kari Argillander <kari.argillander@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-08-19isystem: ship and use stdarg.hAlexey Dobriyan
Ship minimal stdarg.h (1 type, 4 macros) as <linux/stdarg.h>. stdarg.h is the only userspace header commonly used in the kernel. GPL 2 version of <stdarg.h> can be extracted from http://archive.debian.org/debian/pool/main/g/gcc-4.2/gcc-4.2_4.2.4.orig.tar.gz Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-15useful constants: struct qstr for ".."Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-18[PATCH] reduce boilerplate in fsid handlingAl Viro
Get rid of boilerplate in most of ->statfs() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-12fs/ufs: avoid potential u32 multiplication overflowColin Ian King
The 64 bit ino is being compared to the product of two u32 values, however, the multiplication is being performed using a 32 bit multiply so there is a potential of an overflow. To be fully safe, cast uspi->s_ncg to a u64 to ensure a 64 bit multiplication occurs to avoid any chance of overflow. Fixes: f3e2a520f5fb ("ufs: NFS support") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Alexey Dobriyan <adobriyan@gmail.com> Link: http://lkml.kernel.org/r/20200715170355.1081713-1-colin.king@canonical.com Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-30fs: Fill in max and min timestamps in superblockDeepa Dinamani
Fill in the appropriate limits to avoid inconsistencies in the vfs cached inode times when timestamps are outside the permitted range. Even though some filesystems are read-only, fill in the timestamps to reflect the on-disk representation. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Acked-By: Tigran Aivazian <aivazian.tigran@gmail.com> Acked-by: Jeff Layton <jlayton@kernel.org> Cc: aivazian.tigran@gmail.com Cc: al@alarsen.net Cc: coda@cs.cmu.edu Cc: darrick.wong@oracle.com Cc: dushistov@mail.ru Cc: dwmw2@infradead.org Cc: hch@infradead.org Cc: jack@suse.com Cc: jaharkes@cs.cmu.edu Cc: luisbg@kernel.org Cc: nico@fluxnic.net Cc: phillip@squashfs.org.uk Cc: richard@nod.at Cc: salah.triki@gmail.com Cc: shaggy@kernel.org Cc: linux-xfs@vger.kernel.org Cc: codalist@coda.cs.cmu.edu Cc: linux-ext4@vger.kernel.org Cc: linux-mtd@lists.infradead.org Cc: jfs-discussion@lists.sourceforge.net Cc: reiserfs-devel@vger.kernel.org
2019-07-16fs/ufs/super.c: remove set but not used variable 'usb3'YueHaibing
Fixes gcc '-Wunused-but-set-variable' warning: fs/ufs/super.c: In function ufs_statfs: fs/ufs/super.c:1409:32: warning: variable usb3 set but not used [-Wunused-but-set-variable] It is not used since commmit c596961d1b4c ("ufs: fix s_size/s_dsize users") Link: http://lkml.kernel.org/r/20190525140654.15924-1-yuehaibing@huawei.com Signed-off-by: YueHaibing <yuehaibing@huawei.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-21treewide: Add SPDX license identifier for more missed filesThomas Gleixner
Add SPDX license identifiers to all files which: - Have no license information of any form - Have MODULE_LICENCE("GPL*") inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-01ufs: switch to ->free_inode()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-08-17fs/ufs: use ktime_get_real_seconds for sb and cg timestampsArnd Bergmann
get_seconds() is deprecated because of the 32-bit overflow and will be removed. All callers in ufs also truncate to a 32-bit number, so nothing changes during the conversion, but this should be harmless as the superblock and cylinder group timestamps are not visible to user space, except for checking the fs-dirty state, wich works fine across the overflow. This moves the call to get_seconds() into a new inline function, with a comment explaining the constraints, while converting it to ktime_get_real_seconds(). Link: http://lkml.kernel.org/r/20180718115017.742609-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-02-03Merge tag 'usercopy-v4.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardened usercopy whitelisting from Kees Cook: "Currently, hardened usercopy performs dynamic bounds checking on slab cache objects. This is good, but still leaves a lot of kernel memory available to be copied to/from userspace in the face of bugs. To further restrict what memory is available for copying, this creates a way to whitelist specific areas of a given slab cache object for copying to/from userspace, allowing much finer granularity of access control. Slab caches that are never exposed to userspace can declare no whitelist for their objects, thereby keeping them unavailable to userspace via dynamic copy operations. (Note, an implicit form of whitelisting is the use of constant sizes in usercopy operations and get_user()/put_user(); these bypass all hardened usercopy checks since these sizes cannot change at runtime.) This new check is WARN-by-default, so any mistakes can be found over the next several releases without breaking anyone's system. The series has roughly the following sections: - remove %p and improve reporting with offset - prepare infrastructure and whitelist kmalloc - update VFS subsystem with whitelists - update SCSI subsystem with whitelists - update network subsystem with whitelists - update process memory with whitelists - update per-architecture thread_struct with whitelists - update KVM with whitelists and fix ioctl bug - mark all other allocations as not whitelisted - update lkdtm for more sensible test overage" * tag 'usercopy-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (38 commits) lkdtm: Update usercopy tests for whitelisting usercopy: Restrict non-usercopy caches to size 0 kvm: x86: fix KVM_XEN_HVM_CONFIG ioctl kvm: whitelist struct kvm_vcpu_arch arm: Implement thread_struct whitelist for hardened usercopy arm64: Implement thread_struct whitelist for hardened usercopy x86: Implement thread_struct whitelist for hardened usercopy fork: Provide usercopy whitelisting for task_struct fork: Define usercopy region in thread_stack slab caches fork: Define usercopy region in mm_struct slab caches net: Restrict unwhitelisted proto caches to size 0 sctp: Copy struct sctp_sock.autoclose to userspace using put_user() sctp: Define usercopy region in SCTP proto slab cache caif: Define usercopy region in caif proto slab cache ip: Define usercopy region in IP proto slab cache net: Define usercopy region in struct proto slab cache scsi: Define usercopy region in scsi_sense_cache slab cache cifs: Define usercopy region in cifs_request slab cache vxfs: Define usercopy region in vxfs_inode slab cache ufs: Define usercopy region in ufs_inode_cache slab cache ...
2018-01-29ufs: use new i_version APIJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2018-01-15ufs: Define usercopy region in ufs_inode_cache slab cacheDavid Windsor
The ufs symlink pathnames, stored in struct ufs_inode_info.i_u1.i_symlink and therefore contained in the ufs_inode_cache slab cache, need to be copied to/from userspace. cache object allocation: fs/ufs/super.c: ufs_alloc_inode(...): ... ei = kmem_cache_alloc(ufs_inode_cachep, GFP_NOFS); ... return &ei->vfs_inode; fs/ufs/ufs.h: UFS_I(struct inode *inode): return container_of(inode, struct ufs_inode_info, vfs_inode); fs/ufs/namei.c: ufs_symlink(...): ... inode->i_link = (char *)UFS_I(inode)->i_u1.i_symlink; example usage trace: readlink_copy+0x43/0x70 vfs_readlink+0x62/0x110 SyS_readlinkat+0x100/0x130 fs/namei.c: readlink_copy(..., link): ... copy_to_user(..., link, len); (inlined in vfs_readlink) generic_readlink(dentry, ...): struct inode *inode = d_inode(dentry); const char *link = inode->i_link; ... readlink_copy(..., link); In support of usercopy hardening, this patch defines a region in the ufs_inode_cache slab cache in which userspace copy operations are allowed. This region is known as the slab cache's usercopy region. Slab caches can now check that each dynamically sized copy operation involving cache-managed memory falls entirely within the slab's usercopy region. This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY whitelisting code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Signed-off-by: David Windsor <dave@nullcore.net> [kees: adjust commit log, provide usage trace] Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-27Rename superblock flags (MS_xyz -> SB_xyz)Linus Torvalds
This is a pure automated search-and-replace of the internal kernel superblock flags. The s_flags are now called SB_*, with the names and the values for the moment mirroring the MS_* flags that they're equivalent to. Note how the MS_xyz flags are the ones passed to the mount system call, while the SB_xyz flags are what we then use in sb->s_flags. The script to do this was: # places to look in; re security/*: it generally should *not* be # touched (that stuff parses mount(2) arguments directly), but # there are two places where we really deal with superblock flags. FILES="drivers/mtd drivers/staging/lustre fs ipc mm \ include/linux/fs.h include/uapi/linux/bfs_fs.h \ security/apparmor/apparmorfs.c security/apparmor/include/lib.h" # the list of MS_... constants SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \ DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \ POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \ I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \ ACTIVE NOUSER" SED_PROG= for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done # we want files that contain at least one of MS_..., # with fs/namespace.c and fs/pnode.c excluded. L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c') for f in $L; do sed -i $f $SED_PROG; done Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-17VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)David Howells
Firstly by applying the following with coccinelle's spatch: @@ expression SB; @@ -SB->s_flags & MS_RDONLY +sb_rdonly(SB) to effect the conversion to sb_rdonly(sb), then by applying: @@ expression A, SB; @@ ( -(!sb_rdonly(SB)) && A +!sb_rdonly(SB) && A | -A != (sb_rdonly(SB)) +A != sb_rdonly(SB) | -A == (sb_rdonly(SB)) +A == sb_rdonly(SB) | -!(sb_rdonly(SB)) +!sb_rdonly(SB) | -A && (sb_rdonly(SB)) +A && sb_rdonly(SB) | -A || (sb_rdonly(SB)) +A || sb_rdonly(SB) | -(sb_rdonly(SB)) != A +sb_rdonly(SB) != A | -(sb_rdonly(SB)) == A +sb_rdonly(SB) == A | -(sb_rdonly(SB)) && A +sb_rdonly(SB) && A | -(sb_rdonly(SB)) || A +sb_rdonly(SB) || A ) @@ expression A, B, SB; @@ ( -(sb_rdonly(SB)) ? 1 : 0 +sb_rdonly(SB) | -(sb_rdonly(SB)) ? A : B +sb_rdonly(SB) ? A : B ) to remove left over excess bracketage and finally by applying: @@ expression A, SB; @@ ( -(A & MS_RDONLY) != sb_rdonly(SB) +(bool)(A & MS_RDONLY) != sb_rdonly(SB) | -(A & MS_RDONLY) == sb_rdonly(SB) +(bool)(A & MS_RDONLY) == sb_rdonly(SB) ) to make comparisons against the result of sb_rdonly() (which is a bool) work correctly. Signed-off-by: David Howells <dhowells@redhat.com>
2017-06-21Merge branch 'ufs-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more ufs fixes from Al Viro: "More UFS fixes, unfortunately including build regression fix for the 64-bit s_dsize commit. Fixed in this pile: - trivial bug in signedness of 32bit timestamps on ufs1 - ESTALE instead of ufs_error() when doing open-by-fhandle on something deleted - build regression on 32bit in ufs_new_fragments() - calculating that many percents of u64 pulls libgcc stuff on some of those. Mea culpa. - fix hysteresis loop broken by typo in 2.4.14.7 (right next to the location of previous bug). - fix the insane limits of said hysteresis loop on filesystems with very low percentage of reserved blocks. If it's 5% or less, just use the OPTSPACE policy. - calculate those limits once and mount time. This tree does pass xfstests clean (both ufs1 and ufs2) and it _does_ survive cross-builds. Again, my apologies for missing that, especially since I have noticed a related percentage-of-64bit issue in earlier patches (when dealing with amount of reserved blocks). Self-LART applied..." * 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ufs: fix the logics for tail relocation ufs_iget(): fail with -ESTALE on deleted inode fix signedness of timestamps on ufs1
2017-06-17ufs: fix the logics for tail relocationAl Viro
* original hysteresis loop got broken by typo back in 2002; now it never switches out of OPTTIME state. Fixed. * critical levels for switching from OPTTIME to OPTSPACE and back ought to be calculated once, at mount time. * we should use mul_u64_u32_div() for those calculations, now that ->s_dsize is 64bit. * to quote Kirk McKusick (in 1995 FreeBSD commit message): The threshold for switching from time-space and space-time is too small when minfree is 5%...so make it stay at space in this case. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-17Merge branch 'ufs-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull ufs fixes from Al Viro: "Fix assorted ufs bugs: a couple of deadlocks, fs corruption in truncate(), oopsen on tail unpacking and truncate when racing with vmscan, mild fs corruption (free blocks stats summary buggered, *BSD fsck would complain and fix), several instances of broken logics around reserved blocks (starting with "check almost never triggers when it should" and then there are issues with sufficiently large UFS2)" [ Note: ufs hasn't gotten any loving in a long time, because nobody really seems to use it. These ufs fixes are triggered by people actually caring now, not some sudden influx of new bugs. - Linus ] * 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ufs_truncate_blocks(): fix the case when size is in the last direct block ufs: more deadlock prevention on tail unpacking ufs: avoid grabbing ->truncate_mutex if possible ufs_get_locked_page(): make sure we have buffer_heads ufs: fix s_size/s_dsize users ufs: fix reserved blocks check ufs: make ufs_freespace() return signed ufs: fix logics in "ufs: make fsck -f happy"
2017-06-14ufs: fix s_size/s_dsize usersAl Viro
For UFS2 we need 64bit variants; we even store them in uspi, but use 32bit ones instead. One wrinkle is in handling of reserved space - recalculating it every time had been stupid all along, but now it would become really ugly. Just calculate it once... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-14ufs: fix logics in "ufs: make fsck -f happy"Al Viro
Storing stats _only_ at new locations is wrong for UFS1; old locations should always be kept updated. The check for "has been converted to use of new locations" is also wrong - it should be "->fs_maxbsize is equal to ->fs_bsize". Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull UFS fixes from Al Viro: "This is just the obvious backport fodder; I'm pretty sure that there will be more - definitely so wrt performance and quite possibly correctness as well" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ufs: we need to sync inode before freeing it excessive checks in ufs_write_failed() and ufs_evict_inode() ufs_getfrag_block(): we only grab ->truncate_mutex on block creation path ufs_extend_tail(): fix the braino in calling conventions of ufs_new_fragments() ufs: set correct ->s_maxsize ufs: restore maintaining ->i_blocks fix ufs_isblockset() ufs: restore proper tail allocation
2017-06-09ufs: set correct ->s_maxsizeAl Viro
Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-04fs/ufs: Set UFS default maximum bytes per fileRichard Narron
This fixes a problem with reading files larger than 2GB from a UFS-2 file system: https://bugzilla.kernel.org/show_bug.cgi?id=195721 The incorrect UFS s_maxsize limit became a problem as of commit c2a9737f45e2 ("vfs,mm: fix a dead loop in truncate_inode_pages_range()") which started using s_maxbytes to avoid a page index overflow in do_generic_file_read(). That caused files to be truncated on UFS-2 file systems because the default maximum file size is 2GB (MAX_NON_LFS) and UFS didn't update it. Here I simply increase the default to a common value used by other file systems. Signed-off-by: Richard Narron <comet.berkeley@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Will B <will.brokenbourgh2877@gmail.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: <stable@vger.kernel.org> # v4.9 and backports of c2a9737f45e2 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-10don't bother with ->d_inode->i_sb - it's always equal to ->d_sbAl Viro
... and neither can ever be NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-14kmemcg: account certain kmem allocations to memcgVladimir Davydov
Mark those kmem allocations that are known to be easily triggered from userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to memcg. For the list, see below: - threadinfo - task_struct - task_delay_info - pid - cred - mm_struct - vm_area_struct and vm_region (nommu) - anon_vma and anon_vma_chain - signal_struct - sighand_struct - fs_struct - files_struct - fdtable and fdtable->full_fds_bits - dentry and external_name - inode for all filesystems. This is the most tedious part, because most filesystems overwrite the alloc_inode method. The list is far from complete, so feel free to add more objects. Nevertheless, it should be close to "account everything" approach and keep most workloads within bounds. Malevolent users will be able to breach the limit, but this was possible even with the former "account everything" approach (simply because it did not account everything in fact). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tejun Heo <tj@kernel.org> Cc: Greg Thelen <gthelen@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-06ufs: kill lock_ufs()Al Viro
There were 3 remaining users; in two of them we took ->s_lock immediately after lock_ufs() and held it until just before unlock_ufs(); the third one (statfs) could not be called from itself or from other two (remount and sync_fs). Just use ->s_lock in statfs and don't bother with lock_ufs at all. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-06ufs: don't use lock_ufs() for block pointers tree protectionAl Viro
* stores to block pointers are under per-inode seqlock (meta_lock) and mutex (truncate_mutex) * fetches of block pointers are either under truncate_mutex, or wrapped into seqretry loop on meta_lock * all changes of ->i_size are under truncate_mutex and i_mutex * all changes of ->i_lastfrag are under truncate_mutex It's similar to what ext2 is doing; the main difference is that unlike ext2 we can't rely upon the atomicity of stores into block pointers - on UFS2 they are 64bit. So we can't cut the corner when switching a pointer from NULL to non-NULL as we could in ext2_splice_branch() and need to use meta_lock on all modifications. We use seqlock where ext2 uses rwlock; ext2 could probably also benefit from such change... Another non-trivial difference is that with UFS we *cannot* have reader grab truncate_mutex in case of race - it has to keep retrying. That might be possible to change, but not until we lift tail unpacking several levels up in call chain. After that commit we do *NOT* hold fs-wide serialization on accesses to block pointers anymore. Moreover, lock_ufs() can become a normal mutex now - it's only used on statfs, remount and sync_fs and none of those uses are recursive. As the matter of fact, *now* it can be collapsed with ->s_lock, and be eventually replaced with saner per-cylinder-group spinlocks, but that's a separate story. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-07-04Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...
2015-06-17fs/ufs: restore s_lock mutex_init()Fabian Frederick
Add last missing line in commit "cdd9eefdf905" ("fs/ufs: restore s_lock mutex") Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-16fs/ufs: restore s_lock mutexFabian Frederick
Commit 0244756edc4b98c ("ufs: sb mutex merge + mutex_destroy") generated deadlocks in read/write mode on mkdir. This patch partially reverts it keeping fixes by Andrew Morton and mutex_destroy() [AV: fixed a missing bit in ufs_remount()] Signed-off-by: Fabian Frederick <fabf@skynet.be> Reported-by: Ian Campbell <ian.campbell@citrix.com> Suggested-by: Jan Kara <jack@suse.cz> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Alexey Khoroshilov <khoroshilov@ispras.ru> Cc: Roger Pau Monne <roger.pau@citrix.com> Cc: Ian Jackson <Ian.Jackson@eu.citrix.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-02writeback: separate out include/linux/backing-dev-defs.hTejun Heo
With the planned cgroup writeback support, backing-dev related declarations will be more widely used across block and cgroup; unfortunately, including backing-dev.h from include/linux/blkdev.h makes cyclic include dependency quite likely. This patch separates out backing-dev-defs.h which only has the essential definitions and updates blkdev.h to include it. c files which need access to more backing-dev details now include backing-dev.h directly. This takes backing-dev.h off the common include dependency chain making it a lot easier to use it across block and cgroup. v2: fs/fat build failure fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-15VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17fs/ufs/super.c: fix potential race conditionFabian Frederick
Let locking subsystem decide on mutex management. As reported by Andrew Morton this patch fixes a bug: : lock_ufs() is assuming that on non-preempt uniprocessor, the calling : code will run atomically up to the matching unlock_ufs(). : : But that isn't true. The very first site I looked at (ufs_frag_map) : does sb_bread() under lock_ufs(). And sb_bread() will call schedule(), : very commonly. : : The ->mutex_owner stuff is a bit hacky but should work OK. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17fs/ufs/super.c: remove unnecessary castingFabian Frederick
Fix the following coccinelle warning: fs/ufs/super.c:1418:7-28: WARNING: casting value returned by memory allocation function to (struct ufs_inode_info *) is useless. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08fs/ufs: convert UFSD printk to pr_debugFabian Frederick
Convert no level printk to pr_debug in UFSD. DEBUG is defined with CONFIG_UFS_DEBUG so pr_debug are emitted here. Also fixing call to UFSD (add;) Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08fs/ufs/super.c: use va_format instead of buffer/vsnprintfFabian Frederick
Remove error_buffer and use %pV Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08fs/ufs/super.c: use __func__ in loggingFabian Frederick
Replace approximate function name by __func__ using standard format "function():" Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08fs/ufs: use pr_fmtFabian Frederick
Replace UFS-fs, UFS-fs: and UFS: by pr_fmt with module name "ufs: " Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08fs/ufs: convert printk to pr_foo()Fabian Frederick
Use current logging functions. - no level printk under CONFIG_UFS_DEBUG converted to pr_debug - no level printk elsewhere converted to pr_err - add DDEBUG flag in Makefile - coalesce formats Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06ufs: sb mutex merge + mutex_destroyFabian Frederick
Commit 788257d6101d ("ufs: remove the BKL") replaced BKL with mutex protection using functions lock_ufs, unlock_ufs and struct mutex 'mutex' in sb_info. Commit b6963327e052 ("ufs: drop lock/unlock super") removed lock/unlock super and added struct mutex 's_lock' in sb_info. Those 2 mutexes are generally locked/unlocked at the same time except in allocation (balloc, ialloc). This patch merges the 2 mutexes and propagates first commit solution. It also adds mutex destruction before kfree during ufs_fill_super failure and ufs_put_super. [akpm@linux-foundation.org: avoid ifdefs, return -EROFS not -EINVAL] Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: "Chen, Jet" <jet.chen@intel.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07fs/ufs: remove unused ufs_super_block_third pointerChristian Engelmayer
Pointer 'usb3' to struct ufs_super_block_third acquired via ubh_get_usb_third() is never used in function ufs_read_cylinder_structures(). Thus remove it. Detected by Coverity: CID 139939. Signed-off-by: Christian Engelmayer <cengelma@gmx.at> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07fs/ufs: remove unused ufs_super_block_second pointerChristian Engelmayer
Pointer 'usb2' to struct ufs_super_block_second acquired via ubh_get_usb_second() is never used in function ufs_statfs(). Thus remove it. Detected by Coverity: CID 139940. Signed-off-by: Christian Engelmayer <cengelma@gmx.at> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07fs/ufs: remove unused ufs_super_block_first pointerChristian Engelmayer
Remove occurences of unused pointers to struct ufs_super_block_first that were acquired via ubh_get_usb_first(). Detected by Coverity: CID 139929 - CID 139936, CID 139940. Signed-off-by: Christian Engelmayer <cengelma@gmx.at> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07fs/ufs/super.c: add __init to init_inodecache()Fabian Frederick
init_inodecache is only called by __init init_ufs_fs. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-13fs: push sync_filesystem() down to the file system's remount_fs()Theodore Ts'o
Previously, the no-op "mount -o mount /dev/xxx" operation when the file system is already mounted read-write causes an implied, unconditional syncfs(). This seems pretty stupid, and it's certainly documented or guaraunteed to do this, nor is it particularly useful, except in the case where the file system was mounted rw and is getting remounted read-only. However, it's possible that there might be some file systems that are actually depending on this behavior. In most file systems, it's probably fine to only call sync_filesystem() when transitioning from read-write to read-only, and there are some file systems where this is not needed at all (for example, for a pseudo-filesystem or something like romfs). Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: linux-fsdevel@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Artem Bityutskiy <dedekind1@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Jan Kara <jack@suse.cz> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Anders Larsen <al@alarsen.net> Cc: Phillip Lougher <phillip@squashfs.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: xfs@oss.sgi.com Cc: linux-btrfs@vger.kernel.org Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Cc: codalist@coda.cs.cmu.edu Cc: linux-ext4@vger.kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net Cc: fuse-devel@lists.sourceforge.net Cc: cluster-devel@redhat.com Cc: linux-mtd@lists.infradead.org Cc: jfs-discussion@lists.sourceforge.net Cc: linux-nfs@vger.kernel.org Cc: linux-nilfs@vger.kernel.org Cc: linux-ntfs-dev@lists.sourceforge.net Cc: ocfs2-devel@oss.oracle.com Cc: reiserfs-devel@vger.kernel.org
2013-03-03fs: Limit sys_mount to only request filesystem modules.Eric W. Biederman
Modify the request_module to prefix the file system type with "fs-" and add aliases to all of the filesystems that can be built as modules to match. A common practice is to build all of the kernel code and leave code that is not commonly needed as modules, with the result that many users are exposed to any bug anywhere in the kernel. Looking for filesystems with a fs- prefix limits the pool of possible modules that can be loaded by mount to just filesystems trivially making things safer with no real cost. Using aliases means user space can control the policy of which filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf with blacklist and alias directives. Allowing simple, safe, well understood work-arounds to known problematic software. This also addresses a rare but unfortunate problem where the filesystem name is not the same as it's module name and module auto-loading would not work. While writing this patch I saw a handful of such cases. The most significant being autofs that lives in the module autofs4. This is relevant to user namespaces because we can reach the request module in get_fs_type() without having any special permissions, and people get uncomfortable when a user specified string (in this case the filesystem type) goes all of the way to request_module. After having looked at this issue I don't think there is any particular reason to perform any filtering or permission checks beyond making it clear in the module request that we want a filesystem module. The common pattern in the kernel is to call request_module() without regards to the users permissions. In general all a filesystem module does once loaded is call register_filesystem() and go to sleep. Which means there is not much attack surface exposed by loading a filesytem module unless the filesystem is mounted. In a user namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT, which most filesystems do not set today. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Reported-by: Kees Cook <keescook@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-10-09ufs: drop lock/unlock superMarco Stornelli
Removed lock/unlock super. Added a new private s_lock mutex. Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>