| Message ID | 20250122-xattrat-syscall-v2-1-5b360d4fbcb2@kernel.org (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Headers | show |
| Series | [v2] fs: introduce getfsxattrat and setfsxattrat syscalls | expand |
On Wed, Jan 22, 2025 at 03:18:34PM +0100, Andrey Albershteyn wrote: > From: Andrey Albershteyn <aalbersh@redhat.com> > > Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode > extended attributes/flags. The syscalls take parent directory FD and > path to the child together with struct fsxattr. > > This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference > that file don't need to be open. By having this we can manipulated By that you mean that you can use absolute or relative paths instead of file descriptors? > inode extended attributes not only on normal files but also on > special ones. This is not possible with FS_IOC_FSSETXATTR ioctl as > opening special files returns VFS special inode instead of > underlying filesystem one. I'm not following this argument currently. In what sense does opening special files return a VFS special inode and how does that prevent FS_IOC_FSSEETXATTR from working? The inode in static int ioctl_fssetxattr(struct file *file, void __user *argp) { struct mnt_idmap *idmap = file_mnt_idmap(file); struct dentry *dentry = file->f_path.dentry; d_inode(dentry) and your: error = user_path_at(dfd, filename, lookup_flags, &filepath); if (error) goto out; d_inode(filepath.dentry) is the same. > > This patch adds two new syscalls which allows userspace to set > extended inode attributes on special files by using parent directory > to open FS inode. > > Also, as vfs_fileattr_set() is now will be called on special files > too, let's forbid any other attributes except projid and nextents > (symlink can have an extent). > > CC: linux-api@vger.kernel.org > CC: linux-fsdevel@vger.kernel.org > CC: linux-xfs@vger.kernel.org > Signed-off-by: Andrey Albershteyn <aalbersh@redhat.com> > --- > v1: > https://lore.kernel.org/linuxppc-dev/20250109174540.893098-1-aalbersh@kernel.org/ > > Previous discussion: > https://lore.kernel.org/linux-xfs/20240520164624.665269-2-aalbersh@redhat.com/ > > XFS has project quotas which could be attached to a directory. All > new inodes in these directories inherit project ID set on parent > directory. > > The project is created from userspace by opening and calling > FS_IOC_FSSETXATTR on each inode. This is not possible for special > files such as FIFO, SOCK, BLK etc. Therefore, some inodes are left > with empty project ID. Those inodes then are not shown in the quota > accounting but still exist in the directory. Moreover, in the case > when special files are created in the directory with already > existing project quota, these inode inherit extended attributes. > This than leaves them with these attributes without the possibility > to clear them out. This, in turn, prevents userspace from > re-creating quota project on these existing files. > --- > arch/alpha/kernel/syscalls/syscall.tbl | 2 + > arch/arm/tools/syscall.tbl | 2 + > arch/arm64/tools/syscall_32.tbl | 2 + > arch/m68k/kernel/syscalls/syscall.tbl | 2 + > arch/microblaze/kernel/syscalls/syscall.tbl | 2 + > arch/mips/kernel/syscalls/syscall_n32.tbl | 2 + > arch/mips/kernel/syscalls/syscall_n64.tbl | 2 + > arch/mips/kernel/syscalls/syscall_o32.tbl | 2 + > arch/parisc/kernel/syscalls/syscall.tbl | 2 + > arch/powerpc/kernel/syscalls/syscall.tbl | 2 + > arch/s390/kernel/syscalls/syscall.tbl | 2 + > arch/sh/kernel/syscalls/syscall.tbl | 2 + > arch/sparc/kernel/syscalls/syscall.tbl | 2 + > arch/x86/entry/syscalls/syscall_32.tbl | 2 + > arch/x86/entry/syscalls/syscall_64.tbl | 2 + > arch/xtensa/kernel/syscalls/syscall.tbl | 2 + > fs/inode.c | 99 +++++++++++++++++++++++++++++ > fs/ioctl.c | 16 ++++- > include/linux/fileattr.h | 1 + > include/linux/syscalls.h | 4 ++ > include/uapi/asm-generic/unistd.h | 8 ++- > 21 files changed, 157 insertions(+), 3 deletions(-) > > diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl > index c59d53d6d3f3490f976ca179ddfe02e69265ae4d..4b9e687494c16b60c6fd6ca1dc4d6564706a7e25 100644 > --- a/arch/alpha/kernel/syscalls/syscall.tbl > +++ b/arch/alpha/kernel/syscalls/syscall.tbl > @@ -506,3 +506,5 @@ > 574 common getxattrat sys_getxattrat > 575 common listxattrat sys_listxattrat > 576 common removexattrat sys_removexattrat > +577 common getfsxattrat sys_getfsxattrat > +578 common setfsxattrat sys_setfsxattrat > diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl > index 49eeb2ad8dbd8e074c6240417693f23fb328afa8..66466257f3c2debb3e2299f0b608c6740c98cab2 100644 > --- a/arch/arm/tools/syscall.tbl > +++ b/arch/arm/tools/syscall.tbl > @@ -481,3 +481,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/arm64/tools/syscall_32.tbl b/arch/arm64/tools/syscall_32.tbl > index 69a829912a05eb8a3e21ed701d1030e31c0148bc..9c516118b154811d8d11d5696f32817430320dbf 100644 > --- a/arch/arm64/tools/syscall_32.tbl > +++ b/arch/arm64/tools/syscall_32.tbl > @@ -478,3 +478,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl > index f5ed71f1910d09769c845c2d062d99ee0449437c..159476387f394a92ee5e29db89b118c630372db2 100644 > --- a/arch/m68k/kernel/syscalls/syscall.tbl > +++ b/arch/m68k/kernel/syscalls/syscall.tbl > @@ -466,3 +466,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl > index 680f568b77f2cbefc3eacb2517f276041f229b1e..a6d59ee740b58cacf823702003cf9bad17c0d3b7 100644 > --- a/arch/microblaze/kernel/syscalls/syscall.tbl > +++ b/arch/microblaze/kernel/syscalls/syscall.tbl > @@ -472,3 +472,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl > index 0b9b7e25b69ad592642f8533bee9ccfe95ce9626..cfe38fcebe1a0279e11751378d3e71c5ec6b6569 100644 > --- a/arch/mips/kernel/syscalls/syscall_n32.tbl > +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl > @@ -405,3 +405,5 @@ > 464 n32 getxattrat sys_getxattrat > 465 n32 listxattrat sys_listxattrat > 466 n32 removexattrat sys_removexattrat > +467 n32 getfsxattrat sys_getfsxattrat > +468 n32 setfsxattrat sys_setfsxattrat > diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl > index c844cd5cda620b2809a397cdd6f4315ab6a1bfe2..29a0c5974d1aa2f01e33edc0252d75fb97abe230 100644 > --- a/arch/mips/kernel/syscalls/syscall_n64.tbl > +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl > @@ -381,3 +381,5 @@ > 464 n64 getxattrat sys_getxattrat > 465 n64 listxattrat sys_listxattrat > 466 n64 removexattrat sys_removexattrat > +467 n64 getfsxattrat sys_getfsxattrat > +468 n64 setfsxattrat sys_setfsxattrat > diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl > index 349b8aad1159f404103bd2057a1e64e9bf309f18..6c00436807c57c492ba957fcd59af1202231cf80 100644 > --- a/arch/mips/kernel/syscalls/syscall_o32.tbl > +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl > @@ -454,3 +454,5 @@ > 464 o32 getxattrat sys_getxattrat > 465 o32 listxattrat sys_listxattrat > 466 o32 removexattrat sys_removexattrat > +467 o32 getfsxattrat sys_getfsxattrat > +468 o32 setfsxattrat sys_setfsxattrat > diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl > index d9fc94c869657fcfbd7aca1d5f5abc9fae2fb9d8..b3578fac43d6b65167787fcc97d2d09f5a9828e7 100644 > --- a/arch/parisc/kernel/syscalls/syscall.tbl > +++ b/arch/parisc/kernel/syscalls/syscall.tbl > @@ -465,3 +465,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl > index d8b4ab78bef076bd50d49b87dea5060fd8c1686a..808045d82c9465c3bfa96b15947546efe5851e9a 100644 > --- a/arch/powerpc/kernel/syscalls/syscall.tbl > +++ b/arch/powerpc/kernel/syscalls/syscall.tbl > @@ -557,3 +557,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl > index e9115b4d8b635b846e5c9ad6ce229605323723a5..78dfc2c184d4815baf8a9e61c546c9936d58a47c 100644 > --- a/arch/s390/kernel/syscalls/syscall.tbl > +++ b/arch/s390/kernel/syscalls/syscall.tbl > @@ -469,3 +469,5 @@ > 464 common getxattrat sys_getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat sys_setfsxattrat > diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl > index c8cad33bf250ea110de37bd1407f5a43ec5e38f2..d5a5c8339f0ed25ea07c4aba90351d352033c8a0 100644 > --- a/arch/sh/kernel/syscalls/syscall.tbl > +++ b/arch/sh/kernel/syscalls/syscall.tbl > @@ -470,3 +470,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl > index 727f99d333b304b3db0711953a3d91ece18a28eb..817dcd8603bcbffc47f3f59aa3b74b16486453d0 100644 > --- a/arch/sparc/kernel/syscalls/syscall.tbl > +++ b/arch/sparc/kernel/syscalls/syscall.tbl > @@ -512,3 +512,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl > index 4d0fb2fba7e208ae9455459afe11e277321d9f74..b4842c027c5d00c0236b2ba89387c5e2267447bd 100644 > --- a/arch/x86/entry/syscalls/syscall_32.tbl > +++ b/arch/x86/entry/syscalls/syscall_32.tbl > @@ -472,3 +472,5 @@ > 464 i386 getxattrat sys_getxattrat > 465 i386 listxattrat sys_listxattrat > 466 i386 removexattrat sys_removexattrat > +467 i386 getfsxattrat sys_getfsxattrat > +468 i386 setfsxattrat sys_setfsxattrat > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl > index 5eb708bff1c791debd6cfc5322583b2ae53f6437..b6f0a7236aaee624cf9b484239a1068085a8ffe1 100644 > --- a/arch/x86/entry/syscalls/syscall_64.tbl > +++ b/arch/x86/entry/syscalls/syscall_64.tbl > @@ -390,6 +390,8 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > > # > # Due to a historical design error, certain syscalls are numbered differently > diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl > index 37effc1b134eea061f2c350c1d68b4436b65a4dd..425d56be337d1de22f205ac503df61ff86224fee 100644 > --- a/arch/xtensa/kernel/syscalls/syscall.tbl > +++ b/arch/xtensa/kernel/syscalls/syscall.tbl > @@ -437,3 +437,5 @@ > 464 common getxattrat sys_getxattrat > 465 common listxattrat sys_listxattrat > 466 common removexattrat sys_removexattrat > +467 common getfsxattrat sys_getfsxattrat > +468 common setfsxattrat sys_setfsxattrat > diff --git a/fs/inode.c b/fs/inode.c > index 6b4c77268fc0ecace4ac78a9ca777fbffc277f4a..cdecb793b2ab5ab01e2333da4382919b94c7f65f 100644 > --- a/fs/inode.c > +++ b/fs/inode.c > @@ -23,6 +23,9 @@ > #include <linux/rw_hint.h> > #include <linux/seq_file.h> > #include <linux/debugfs.h> > +#include <linux/syscalls.h> > +#include <linux/fileattr.h> > +#include <linux/namei.h> > #include <trace/events/writeback.h> > #define CREATE_TRACE_POINTS > #include <trace/events/timestamp.h> > @@ -2953,3 +2956,99 @@ umode_t mode_strip_sgid(struct mnt_idmap *idmap, > return mode & ~S_ISGID; > } > EXPORT_SYMBOL(mode_strip_sgid); > + > +SYSCALL_DEFINE4(getfsxattrat, int, dfd, const char __user *, filename, > + struct fsxattr __user *, fsx, unsigned int, at_flags) > +{ > + struct fd dir; > + struct fileattr fa; > + struct path filepath; > + int error; > + unsigned int lookup_flags = 0; > + > + if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) > + return -EINVAL; > + > + if (at_flags & AT_SYMLINK_FOLLOW) > + lookup_flags |= LOOKUP_FOLLOW; > + > + if (at_flags & AT_EMPTY_PATH) > + lookup_flags |= LOOKUP_EMPTY; > + > + dir = fdget(dfd); > + if (!fd_file(dir)) > + return -EBADF; Please rely on scope-based cleanup: CLASS(fd, f)(dfd); if (fd_empty(f)) return -EBADF; > + > + if (!S_ISDIR(file_inode(fd_file(dir))->i_mode)) { This isn't needed as user_path_at() will return ENOTDIR. Your path as is wuld also preclude AT_EMPTY_PATH with directory file descriptors and afaict there's various filesystems that seem to support this on directory inodes. > + error = -EBADF; > + goto out; > + } > + > + error = user_path_at(dfd, filename, lookup_flags, &filepath); > + if (error) > + goto out; I'm confused. You're using fdget() above but then you don't use the resulting file and call user_path_at() instead? Don't bother with fdget() at all and just call into user_path_at() directly. > + > + error = vfs_fileattr_get(filepath.dentry, &fa); > + if (error) > + goto out_path; > + > + if (copy_fsxattr_to_user(&fa, fsx)) > + error = -EFAULT; > + > +out_path: > + path_put(&filepath); > +out: > + fdput(dir); > + return error; > +} > + > +SYSCALL_DEFINE4(setfsxattrat, int, dfd, const char __user *, filename, > + struct fsxattr __user *, fsx, unsigned int, at_flags) > +{ > + struct fd dir; > + struct fileattr fa; > + struct path filepath; > + int error; > + unsigned int lookup_flags = 0; > + > + if ((at_flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) > + return -EINVAL; > + > + if (at_flags & AT_SYMLINK_FOLLOW) > + lookup_flags |= LOOKUP_FOLLOW; > + > + if (at_flags & AT_EMPTY_PATH) > + lookup_flags |= LOOKUP_EMPTY; > + > + dir = fdget(dfd); > + if (!fd_file(dir)) > + return -EBADF; > + > + if (!S_ISDIR(file_inode(fd_file(dir))->i_mode)) { > + error = -EBADF; > + goto out; > + } > + > + if (copy_fsxattr_from_user(&fa, fsx)) { > + error = -EFAULT; > + goto out; > + } > + > + error = user_path_at(dfd, filename, lookup_flags, &filepath); > + if (error) > + goto out; Same problem as above. fdget() stuff isn't needed if you're calling user_path_at() anyway. > + > + error = mnt_want_write(filepath.mnt); > + if (error) > + goto out_path; > + > + error = vfs_fileattr_set(file_mnt_idmap(fd_file(dir)), filepath.dentry, > + &fa); > + mnt_drop_write(filepath.mnt); Just use the pattern: error = user_path_at(dfd, filename, lookup_flags, &filepath); if (error) return error; /* once you've removed the fdget() direct return works fine */ error = mnt_want_write(filepath.mnt); if (!error) { error = vfs_fileattr_set(file_mnt_idmap(fd_file(dir)), filepath.dentry, &fa); mnt_drop_write(filepath.mnt); } return error; > + > +out_path: > + path_put(&filepath); > +out: > + fdput(dir); > + return error; > +} > diff --git a/fs/ioctl.c b/fs/ioctl.c > index 638a36be31c14afc66a7fd6eb237d9545e8ad997..dc160c2ef145e4931d625f1f93c2a8ae7f87abf3 100644 > --- a/fs/ioctl.c > +++ b/fs/ioctl.c > @@ -558,8 +558,7 @@ int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa) > } > EXPORT_SYMBOL(copy_fsxattr_to_user); > > -static int copy_fsxattr_from_user(struct fileattr *fa, > - struct fsxattr __user *ufa) > +int copy_fsxattr_from_user(struct fileattr *fa, struct fsxattr __user *ufa) > { > struct fsxattr xfa; > > @@ -646,6 +645,19 @@ static int fileattr_set_prepare(struct inode *inode, > if (fa->fsx_cowextsize == 0) > fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE; > > + /* > + * The only use case for special files is to set project ID, forbid any > + * other attributes > + */ > + if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))) { > + if (fa->fsx_xflags & ~FS_XFLAG_PROJINHERIT) > + return -EINVAL; > + if (!S_ISLNK(inode->i_mode) && fa->fsx_nextents) > + return -EINVAL; > + if (fa->fsx_extsize || fa->fsx_cowextsize) > + return -EINVAL; > + } > + > return 0; > } > > diff --git a/include/linux/fileattr.h b/include/linux/fileattr.h > index 47c05a9851d0600964b644c9c7218faacfd865f8..8598e94b530b8b280a2697eaf918dd60f573d6ee 100644 > --- a/include/linux/fileattr.h > +++ b/include/linux/fileattr.h > @@ -34,6 +34,7 @@ struct fileattr { > }; > > int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa); > +int copy_fsxattr_from_user(struct fileattr *fa, struct fsxattr __user *ufa); > > void fileattr_fill_xflags(struct fileattr *fa, u32 xflags); > void fileattr_fill_flags(struct fileattr *fa, u32 flags); > diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h > index c6333204d45130eb022f6db460eea34a1f6e91db..3134d463d9af64c6e78adb37bff4b91f77b5305f 100644 > --- a/include/linux/syscalls.h > +++ b/include/linux/syscalls.h > @@ -371,6 +371,10 @@ asmlinkage long sys_removexattrat(int dfd, const char __user *path, > asmlinkage long sys_lremovexattr(const char __user *path, > const char __user *name); > asmlinkage long sys_fremovexattr(int fd, const char __user *name); > +asmlinkage long sys_getfsxattrat(int dfd, const char __user *filename, > + struct fsxattr *fsx, unsigned int at_flags); > +asmlinkage long sys_setfsxattrat(int dfd, const char __user *filename, > + struct fsxattr *fsx, unsigned int at_flags); > asmlinkage long sys_getcwd(char __user *buf, unsigned long size); > asmlinkage long sys_eventfd2(unsigned int count, int flags); > asmlinkage long sys_epoll_create1(int flags); > diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h > index 88dc393c2bca38c0fa1b3fae579f7cfe4931223c..50be2e1007bc2779120d05c6e9512a689f86779c 100644 > --- a/include/uapi/asm-generic/unistd.h > +++ b/include/uapi/asm-generic/unistd.h > @@ -850,8 +850,14 @@ __SYSCALL(__NR_listxattrat, sys_listxattrat) > #define __NR_removexattrat 466 > __SYSCALL(__NR_removexattrat, sys_removexattrat) > > +/* fs/inode.c */ > +#define __NR_getfsxattrat 467 > +__SYSCALL(__NR_getfsxattrat, sys_getfsxattrat) > +#define __NR_setfsxattrat 468 > +__SYSCALL(__NR_setfsxattrat, sys_setfsxattrat) > + > #undef __NR_syscalls > -#define __NR_syscalls 467 > +#define __NR_syscalls 469 > > /* > * 32 bit systems traditionally used different > > --- > base-commit: 4c538044ee2d11299cc57ac1e92d343e1e83b847 > change-id: 20250114-xattrat-syscall-6a1136d2db59 > > Best regards, > -- > Andrey Albershteyn <aalbersh@kernel.org> >
On 2025-01-24 10:33:54, Christian Brauner wrote: > On Wed, Jan 22, 2025 at 03:18:34PM +0100, Andrey Albershteyn wrote: > > From: Andrey Albershteyn <aalbersh@redhat.com> > > > > Introduce getfsxattrat and setfsxattrat syscalls to manipulate inode > > extended attributes/flags. The syscalls take parent directory FD and > > path to the child together with struct fsxattr. > > > > This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference > > that file don't need to be open. By having this we can manipulated > > By that you mean that you can use absolute or relative paths instead of > file descriptors? yes > > > inode extended attributes not only on normal files but also on > > special ones. This is not possible with FS_IOC_FSSETXATTR ioctl as > > opening special files returns VFS special inode instead of > > underlying filesystem one. > > I'm not following this argument currently. In what sense does opening > special files return a VFS special inode and how does that prevent > FS_IOC_FSSEETXATTR from working? The inode in > > static int ioctl_fssetxattr(struct file *file, void __user *argp) > { > struct mnt_idmap *idmap = file_mnt_idmap(file); > struct dentry *dentry = file->f_path.dentry; > > d_inode(dentry) > > > and your: > > error = user_path_at(dfd, filename, lookup_flags, &filepath); > if (error) > goto out; > > d_inode(filepath.dentry) > > is the same. This is probably not a good description. With these special files, like pipe, we can not just open them to call FS_IOC_FSSETXATTR, as with regular ones. As you asked above, with filepath it can be done without opening files in userspace. I don't see how we can open() special files and then call ioctl() on them and with paths we can do it pretty easily. > > > > > This patch adds two new syscalls which allows userspace to set > > extended inode attributes on special files by using parent directory > > to open FS inode. > > > > Also, as vfs_fileattr_set() is now will be called on special files > > too, let's forbid any other attributes except projid and nextents > > (symlink can have an extent). > > > > CC: linux-api@vger.kernel.org > > CC: linux-fsdevel@vger.kernel.org > > CC: linux-xfs@vger.kernel.org > > Signed-off-by: Andrey Albershteyn <aalbersh@redhat.com> > > --- > > v1: > > https://lore.kernel.org/linuxppc-dev/20250109174540.893098-1-aalbersh@kernel.org/ > > > > Previous discussion: > > https://lore.kernel.org/linux-xfs/20240520164624.665269-2-aalbersh@redhat.com/ > > > > XFS has project quotas which could be attached to a directory. All > > new inodes in these directories inherit project ID set on parent > > directory. > > > > The project is created from userspace by opening and calling > > FS_IOC_FSSETXATTR on each inode. This is not possible for special > > files such as FIFO, SOCK, BLK etc. Therefore, some inodes are left > > with empty project ID. Those inodes then are not shown in the quota > > accounting but still exist in the directory. Moreover, in the case > > when special files are created in the directory with already > > existing project quota, these inode inherit extended attributes. > > This than leaves them with these attributes without the possibility > > to clear them out. This, in turn, prevents userspace from > > re-creating quota project on these existing files. > > --- > > arch/alpha/kernel/syscalls/syscall.tbl | 2 + > > arch/arm/tools/syscall.tbl | 2 + > > arch/arm64/tools/syscall_32.tbl | 2 + > > arch/m68k/kernel/syscalls/syscall.tbl | 2 + > > arch/microblaze/kernel/syscalls/syscall.tbl | 2 + > > arch/mips/kernel/syscalls/syscall_n32.tbl | 2 + > > arch/mips/kernel/syscalls/syscall_n64.tbl | 2 + > > arch/mips/kernel/syscalls/syscall_o32.tbl | 2 + > > arch/parisc/kernel/syscalls/syscall.tbl | 2 + > > arch/powerpc/kernel/syscalls/syscall.tbl | 2 + > > arch/s390/kernel/syscalls/syscall.tbl | 2 + > > arch/sh/kernel/syscalls/syscall.tbl | 2 + > > arch/sparc/kernel/syscalls/syscall.tbl | 2 + > > arch/x86/entry/syscalls/syscall_32.tbl | 2 + > > arch/x86/entry/syscalls/syscall_64.tbl | 2 + > > arch/xtensa/kernel/syscalls/syscall.tbl | 2 + > > fs/inode.c | 99 +++++++++++++++++++++++++++++ > > fs/ioctl.c | 16 ++++- > > include/linux/fileattr.h | 1 + > > include/linux/syscalls.h | 4 ++ > > include/uapi/asm-generic/unistd.h | 8 ++- > > 21 files changed, 157 insertions(+), 3 deletions(-) > > > > diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl > > index c59d53d6d3f3490f976ca179ddfe02e69265ae4d..4b9e687494c16b60c6fd6ca1dc4d6564706a7e25 100644 > > --- a/arch/alpha/kernel/syscalls/syscall.tbl > > +++ b/arch/alpha/kernel/syscalls/syscall.tbl > > @@ -506,3 +506,5 @@ > > 574 common getxattrat sys_getxattrat > > 575 common listxattrat sys_listxattrat > > 576 common removexattrat sys_removexattrat > > +577 common getfsxattrat sys_getfsxattrat > > +578 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl > > index 49eeb2ad8dbd8e074c6240417693f23fb328afa8..66466257f3c2debb3e2299f0b608c6740c98cab2 100644 > > --- a/arch/arm/tools/syscall.tbl > > +++ b/arch/arm/tools/syscall.tbl > > @@ -481,3 +481,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/arm64/tools/syscall_32.tbl b/arch/arm64/tools/syscall_32.tbl > > index 69a829912a05eb8a3e21ed701d1030e31c0148bc..9c516118b154811d8d11d5696f32817430320dbf 100644 > > --- a/arch/arm64/tools/syscall_32.tbl > > +++ b/arch/arm64/tools/syscall_32.tbl > > @@ -478,3 +478,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl > > index f5ed71f1910d09769c845c2d062d99ee0449437c..159476387f394a92ee5e29db89b118c630372db2 100644 > > --- a/arch/m68k/kernel/syscalls/syscall.tbl > > +++ b/arch/m68k/kernel/syscalls/syscall.tbl > > @@ -466,3 +466,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl > > index 680f568b77f2cbefc3eacb2517f276041f229b1e..a6d59ee740b58cacf823702003cf9bad17c0d3b7 100644 > > --- a/arch/microblaze/kernel/syscalls/syscall.tbl > > +++ b/arch/microblaze/kernel/syscalls/syscall.tbl > > @@ -472,3 +472,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl > > index 0b9b7e25b69ad592642f8533bee9ccfe95ce9626..cfe38fcebe1a0279e11751378d3e71c5ec6b6569 100644 > > --- a/arch/mips/kernel/syscalls/syscall_n32.tbl > > +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl > > @@ -405,3 +405,5 @@ > > 464 n32 getxattrat sys_getxattrat > > 465 n32 listxattrat sys_listxattrat > > 466 n32 removexattrat sys_removexattrat > > +467 n32 getfsxattrat sys_getfsxattrat > > +468 n32 setfsxattrat sys_setfsxattrat > > diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl > > index c844cd5cda620b2809a397cdd6f4315ab6a1bfe2..29a0c5974d1aa2f01e33edc0252d75fb97abe230 100644 > > --- a/arch/mips/kernel/syscalls/syscall_n64.tbl > > +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl > > @@ -381,3 +381,5 @@ > > 464 n64 getxattrat sys_getxattrat > > 465 n64 listxattrat sys_listxattrat > > 466 n64 removexattrat sys_removexattrat > > +467 n64 getfsxattrat sys_getfsxattrat > > +468 n64 setfsxattrat sys_setfsxattrat > > diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl > > index 349b8aad1159f404103bd2057a1e64e9bf309f18..6c00436807c57c492ba957fcd59af1202231cf80 100644 > > --- a/arch/mips/kernel/syscalls/syscall_o32.tbl > > +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl > > @@ -454,3 +454,5 @@ > > 464 o32 getxattrat sys_getxattrat > > 465 o32 listxattrat sys_listxattrat > > 466 o32 removexattrat sys_removexattrat > > +467 o32 getfsxattrat sys_getfsxattrat > > +468 o32 setfsxattrat sys_setfsxattrat > > diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl > > index d9fc94c869657fcfbd7aca1d5f5abc9fae2fb9d8..b3578fac43d6b65167787fcc97d2d09f5a9828e7 100644 > > --- a/arch/parisc/kernel/syscalls/syscall.tbl > > +++ b/arch/parisc/kernel/syscalls/syscall.tbl > > @@ -465,3 +465,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl > > index d8b4ab78bef076bd50d49b87dea5060fd8c1686a..808045d82c9465c3bfa96b15947546efe5851e9a 100644 > > --- a/arch/powerpc/kernel/syscalls/syscall.tbl > > +++ b/arch/powerpc/kernel/syscalls/syscall.tbl > > @@ -557,3 +557,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl > > index e9115b4d8b635b846e5c9ad6ce229605323723a5..78dfc2c184d4815baf8a9e61c546c9936d58a47c 100644 > > --- a/arch/s390/kernel/syscalls/syscall.tbl > > +++ b/arch/s390/kernel/syscalls/syscall.tbl > > @@ -469,3 +469,5 @@ > > 464 common getxattrat sys_getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat sys_setfsxattrat > > diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl > > index c8cad33bf250ea110de37bd1407f5a43ec5e38f2..d5a5c8339f0ed25ea07c4aba90351d352033c8a0 100644 > > --- a/arch/sh/kernel/syscalls/syscall.tbl > > +++ b/arch/sh/kernel/syscalls/syscall.tbl > > @@ -470,3 +470,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl > > index 727f99d333b304b3db0711953a3d91ece18a28eb..817dcd8603bcbffc47f3f59aa3b74b16486453d0 100644 > > --- a/arch/sparc/kernel/syscalls/syscall.tbl > > +++ b/arch/sparc/kernel/syscalls/syscall.tbl > > @@ -512,3 +512,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl > > index 4d0fb2fba7e208ae9455459afe11e277321d9f74..b4842c027c5d00c0236b2ba89387c5e2267447bd 100644 > > --- a/arch/x86/entry/syscalls/syscall_32.tbl > > +++ b/arch/x86/entry/syscalls/syscall_32.tbl > > @@ -472,3 +472,5 @@ > > 464 i386 getxattrat sys_getxattrat > > 465 i386 listxattrat sys_listxattrat > > 466 i386 removexattrat sys_removexattrat > > +467 i386 getfsxattrat sys_getfsxattrat > > +468 i386 setfsxattrat sys_setfsxattrat > > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl > > index 5eb708bff1c791debd6cfc5322583b2ae53f6437..b6f0a7236aaee624cf9b484239a1068085a8ffe1 100644 > > --- a/arch/x86/entry/syscalls/syscall_64.tbl > > +++ b/arch/x86/entry/syscalls/syscall_64.tbl > > @@ -390,6 +390,8 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > > > # > > # Due to a historical design error, certain syscalls are numbered differently > > diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl > > index 37effc1b134eea061f2c350c1d68b4436b65a4dd..425d56be337d1de22f205ac503df61ff86224fee 100644 > > --- a/arch/xtensa/kernel/syscalls/syscall.tbl > > +++ b/arch/xtensa/kernel/syscalls/syscall.tbl > > @@ -437,3 +437,5 @@ > > 464 common getxattrat sys_getxattrat > > 465 common listxattrat sys_listxattrat > > 466 common removexattrat sys_removexattrat > > +467 common getfsxattrat sys_getfsxattrat > > +468 common setfsxattrat sys_setfsxattrat > > diff --git a/fs/inode.c b/fs/inode.c > > index 6b4c77268fc0ecace4ac78a9ca777fbffc277f4a..cdecb793b2ab5ab01e2333da4382919b94c7f65f 100644 > > --- a/fs/inode.c > > +++ b/fs/inode.c > > @@ -23,6 +23,9 @@ > > #include <linux/rw_hint.h> > > #include <linux/seq_file.h> > > #include <linux/debugfs.h> > > +#include <linux/syscalls.h> > > +#include <linux/fileattr.h> > > +#include <linux/namei.h> > > #include <trace/events/writeback.h> > > #define CREATE_TRACE_POINTS > > #include <trace/events/timestamp.h> > > @@ -2953,3 +2956,99 @@ umode_t mode_strip_sgid(struct mnt_idmap *idmap, > > return mode & ~S_ISGID; > > } > > EXPORT_SYMBOL(mode_strip_sgid); > > + > > +SYSCALL_DEFINE4(getfsxattrat, int, dfd, const char __user *, filename, > > + struct fsxattr __user *, fsx, unsigned int, at_flags) > > +{ > > + struct fd dir; > > + struct fileattr fa; > > + struct path filepath; > > + int error; > > + unsigned int lookup_flags = 0; > > + > > + if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) > > + return -EINVAL; > > + > > + if (at_flags & AT_SYMLINK_FOLLOW) > > + lookup_flags |= LOOKUP_FOLLOW; > > + > > + if (at_flags & AT_EMPTY_PATH) > > + lookup_flags |= LOOKUP_EMPTY; > > + > > + dir = fdget(dfd); > > + if (!fd_file(dir)) > > + return -EBADF; > > Please rely on scope-based cleanup: > > CLASS(fd, f)(dfd); > if (fd_empty(f)) > return -EBADF; aha, thanks, didn't know about this > > > + > > + if (!S_ISDIR(file_inode(fd_file(dir))->i_mode)) { > > This isn't needed as user_path_at() will return ENOTDIR. > Your path as is wuld also preclude AT_EMPTY_PATH with directory file > descriptors and afaict there's various filesystems that seem to support > this on directory inodes. I see, thanks, I will remove that > > > + error = -EBADF; > > + goto out; > > + } > > + > > + error = user_path_at(dfd, filename, lookup_flags, &filepath); > > + if (error) > > + goto out; > > I'm confused. You're using fdget() above but then you don't use the > resulting file and call user_path_at() instead? Don't bother with > fdget() at all and just call into user_path_at() directly. sure, doesn't needed anymore with your suggestions above > > > + > > + error = vfs_fileattr_get(filepath.dentry, &fa); > > + if (error) > > + goto out_path; > > + > > + if (copy_fsxattr_to_user(&fa, fsx)) > > + error = -EFAULT; > > + > > +out_path: > > + path_put(&filepath); > > +out: > > + fdput(dir); > > + return error; > > +} > > + > > +SYSCALL_DEFINE4(setfsxattrat, int, dfd, const char __user *, filename, > > + struct fsxattr __user *, fsx, unsigned int, at_flags) > > +{ > > + struct fd dir; > > + struct fileattr fa; > > + struct path filepath; > > + int error; > > + unsigned int lookup_flags = 0; > > + > > + if ((at_flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) > > + return -EINVAL; > > + > > + if (at_flags & AT_SYMLINK_FOLLOW) > > + lookup_flags |= LOOKUP_FOLLOW; > > + > > + if (at_flags & AT_EMPTY_PATH) > > + lookup_flags |= LOOKUP_EMPTY; > > + > > + dir = fdget(dfd); > > + if (!fd_file(dir)) > > + return -EBADF; > > + > > + if (!S_ISDIR(file_inode(fd_file(dir))->i_mode)) { > > + error = -EBADF; > > + goto out; > > + } > > + > > + if (copy_fsxattr_from_user(&fa, fsx)) { > > + error = -EFAULT; > > + goto out; > > + } > > + > > + error = user_path_at(dfd, filename, lookup_flags, &filepath); > > + if (error) > > + goto out; > > Same problem as above. fdget() stuff isn't needed if you're calling > user_path_at() anyway. > > > + > > + error = mnt_want_write(filepath.mnt); > > + if (error) > > + goto out_path; > > + > > + error = vfs_fileattr_set(file_mnt_idmap(fd_file(dir)), filepath.dentry, > > + &fa); > > + mnt_drop_write(filepath.mnt); > > Just use the pattern: > > error = user_path_at(dfd, filename, lookup_flags, &filepath); > if (error) > return error; /* once you've removed the fdget() direct return works fine */ > > > error = mnt_want_write(filepath.mnt); > if (!error) { > error = vfs_fileattr_set(file_mnt_idmap(fd_file(dir)), filepath.dentry, &fa); > mnt_drop_write(filepath.mnt); > } > > return error; sure, I will changed it as suggested
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index c59d53d6d3f3490f976ca179ddfe02e69265ae4d..4b9e687494c16b60c6fd6ca1dc4d6564706a7e25 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -506,3 +506,5 @@ 574 common getxattrat sys_getxattrat 575 common listxattrat sys_listxattrat 576 common removexattrat sys_removexattrat +577 common getfsxattrat sys_getfsxattrat +578 common setfsxattrat sys_setfsxattrat diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index 49eeb2ad8dbd8e074c6240417693f23fb328afa8..66466257f3c2debb3e2299f0b608c6740c98cab2 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -481,3 +481,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/arm64/tools/syscall_32.tbl b/arch/arm64/tools/syscall_32.tbl index 69a829912a05eb8a3e21ed701d1030e31c0148bc..9c516118b154811d8d11d5696f32817430320dbf 100644 --- a/arch/arm64/tools/syscall_32.tbl +++ b/arch/arm64/tools/syscall_32.tbl @@ -478,3 +478,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl index f5ed71f1910d09769c845c2d062d99ee0449437c..159476387f394a92ee5e29db89b118c630372db2 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -466,3 +466,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl index 680f568b77f2cbefc3eacb2517f276041f229b1e..a6d59ee740b58cacf823702003cf9bad17c0d3b7 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -472,3 +472,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index 0b9b7e25b69ad592642f8533bee9ccfe95ce9626..cfe38fcebe1a0279e11751378d3e71c5ec6b6569 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -405,3 +405,5 @@ 464 n32 getxattrat sys_getxattrat 465 n32 listxattrat sys_listxattrat 466 n32 removexattrat sys_removexattrat +467 n32 getfsxattrat sys_getfsxattrat +468 n32 setfsxattrat sys_setfsxattrat diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl index c844cd5cda620b2809a397cdd6f4315ab6a1bfe2..29a0c5974d1aa2f01e33edc0252d75fb97abe230 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -381,3 +381,5 @@ 464 n64 getxattrat sys_getxattrat 465 n64 listxattrat sys_listxattrat 466 n64 removexattrat sys_removexattrat +467 n64 getfsxattrat sys_getfsxattrat +468 n64 setfsxattrat sys_setfsxattrat diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index 349b8aad1159f404103bd2057a1e64e9bf309f18..6c00436807c57c492ba957fcd59af1202231cf80 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -454,3 +454,5 @@ 464 o32 getxattrat sys_getxattrat 465 o32 listxattrat sys_listxattrat 466 o32 removexattrat sys_removexattrat +467 o32 getfsxattrat sys_getfsxattrat +468 o32 setfsxattrat sys_setfsxattrat diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index d9fc94c869657fcfbd7aca1d5f5abc9fae2fb9d8..b3578fac43d6b65167787fcc97d2d09f5a9828e7 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -465,3 +465,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index d8b4ab78bef076bd50d49b87dea5060fd8c1686a..808045d82c9465c3bfa96b15947546efe5851e9a 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -557,3 +557,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index e9115b4d8b635b846e5c9ad6ce229605323723a5..78dfc2c184d4815baf8a9e61c546c9936d58a47c 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -469,3 +469,5 @@ 464 common getxattrat sys_getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat sys_setfsxattrat diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl index c8cad33bf250ea110de37bd1407f5a43ec5e38f2..d5a5c8339f0ed25ea07c4aba90351d352033c8a0 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -470,3 +470,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index 727f99d333b304b3db0711953a3d91ece18a28eb..817dcd8603bcbffc47f3f59aa3b74b16486453d0 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -512,3 +512,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 4d0fb2fba7e208ae9455459afe11e277321d9f74..b4842c027c5d00c0236b2ba89387c5e2267447bd 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -472,3 +472,5 @@ 464 i386 getxattrat sys_getxattrat 465 i386 listxattrat sys_listxattrat 466 i386 removexattrat sys_removexattrat +467 i386 getfsxattrat sys_getfsxattrat +468 i386 setfsxattrat sys_setfsxattrat diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 5eb708bff1c791debd6cfc5322583b2ae53f6437..b6f0a7236aaee624cf9b484239a1068085a8ffe1 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -390,6 +390,8 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl index 37effc1b134eea061f2c350c1d68b4436b65a4dd..425d56be337d1de22f205ac503df61ff86224fee 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -437,3 +437,5 @@ 464 common getxattrat sys_getxattrat 465 common listxattrat sys_listxattrat 466 common removexattrat sys_removexattrat +467 common getfsxattrat sys_getfsxattrat +468 common setfsxattrat sys_setfsxattrat diff --git a/fs/inode.c b/fs/inode.c index 6b4c77268fc0ecace4ac78a9ca777fbffc277f4a..cdecb793b2ab5ab01e2333da4382919b94c7f65f 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -23,6 +23,9 @@ #include <linux/rw_hint.h> #include <linux/seq_file.h> #include <linux/debugfs.h> +#include <linux/syscalls.h> +#include <linux/fileattr.h> +#include <linux/namei.h> #include <trace/events/writeback.h> #define CREATE_TRACE_POINTS #include <trace/events/timestamp.h> @@ -2953,3 +2956,99 @@ umode_t mode_strip_sgid(struct mnt_idmap *idmap, return mode & ~S_ISGID; } EXPORT_SYMBOL(mode_strip_sgid); + +SYSCALL_DEFINE4(getfsxattrat, int, dfd, const char __user *, filename, + struct fsxattr __user *, fsx, unsigned int, at_flags) +{ + struct fd dir; + struct fileattr fa; + struct path filepath; + int error; + unsigned int lookup_flags = 0; + + if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) + return -EINVAL; + + if (at_flags & AT_SYMLINK_FOLLOW) + lookup_flags |= LOOKUP_FOLLOW; + + if (at_flags & AT_EMPTY_PATH) + lookup_flags |= LOOKUP_EMPTY; + + dir = fdget(dfd); + if (!fd_file(dir)) + return -EBADF; + + if (!S_ISDIR(file_inode(fd_file(dir))->i_mode)) { + error = -EBADF; + goto out; + } + + error = user_path_at(dfd, filename, lookup_flags, &filepath); + if (error) + goto out; + + error = vfs_fileattr_get(filepath.dentry, &fa); + if (error) + goto out_path; + + if (copy_fsxattr_to_user(&fa, fsx)) + error = -EFAULT; + +out_path: + path_put(&filepath); +out: + fdput(dir); + return error; +} + +SYSCALL_DEFINE4(setfsxattrat, int, dfd, const char __user *, filename, + struct fsxattr __user *, fsx, unsigned int, at_flags) +{ + struct fd dir; + struct fileattr fa; + struct path filepath; + int error; + unsigned int lookup_flags = 0; + + if ((at_flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) + return -EINVAL; + + if (at_flags & AT_SYMLINK_FOLLOW) + lookup_flags |= LOOKUP_FOLLOW; + + if (at_flags & AT_EMPTY_PATH) + lookup_flags |= LOOKUP_EMPTY; + + dir = fdget(dfd); + if (!fd_file(dir)) + return -EBADF; + + if (!S_ISDIR(file_inode(fd_file(dir))->i_mode)) { + error = -EBADF; + goto out; + } + + if (copy_fsxattr_from_user(&fa, fsx)) { + error = -EFAULT; + goto out; + } + + error = user_path_at(dfd, filename, lookup_flags, &filepath); + if (error) + goto out; + + error = mnt_want_write(filepath.mnt); + if (error) + goto out_path; + + error = vfs_fileattr_set(file_mnt_idmap(fd_file(dir)), filepath.dentry, + &fa); + mnt_drop_write(filepath.mnt); + +out_path: + path_put(&filepath); +out: + fdput(dir); + return error; +} diff --git a/fs/ioctl.c b/fs/ioctl.c index 638a36be31c14afc66a7fd6eb237d9545e8ad997..dc160c2ef145e4931d625f1f93c2a8ae7f87abf3 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -558,8 +558,7 @@ int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa) } EXPORT_SYMBOL(copy_fsxattr_to_user); -static int copy_fsxattr_from_user(struct fileattr *fa, - struct fsxattr __user *ufa) +int copy_fsxattr_from_user(struct fileattr *fa, struct fsxattr __user *ufa) { struct fsxattr xfa; @@ -646,6 +645,19 @@ static int fileattr_set_prepare(struct inode *inode, if (fa->fsx_cowextsize == 0) fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE; + /* + * The only use case for special files is to set project ID, forbid any + * other attributes + */ + if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))) { + if (fa->fsx_xflags & ~FS_XFLAG_PROJINHERIT) + return -EINVAL; + if (!S_ISLNK(inode->i_mode) && fa->fsx_nextents) + return -EINVAL; + if (fa->fsx_extsize || fa->fsx_cowextsize) + return -EINVAL; + } + return 0; } diff --git a/include/linux/fileattr.h b/include/linux/fileattr.h index 47c05a9851d0600964b644c9c7218faacfd865f8..8598e94b530b8b280a2697eaf918dd60f573d6ee 100644 --- a/include/linux/fileattr.h +++ b/include/linux/fileattr.h @@ -34,6 +34,7 @@ struct fileattr { }; int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa); +int copy_fsxattr_from_user(struct fileattr *fa, struct fsxattr __user *ufa); void fileattr_fill_xflags(struct fileattr *fa, u32 xflags); void fileattr_fill_flags(struct fileattr *fa, u32 flags); diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index c6333204d45130eb022f6db460eea34a1f6e91db..3134d463d9af64c6e78adb37bff4b91f77b5305f 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -371,6 +371,10 @@ asmlinkage long sys_removexattrat(int dfd, const char __user *path, asmlinkage long sys_lremovexattr(const char __user *path, const char __user *name); asmlinkage long sys_fremovexattr(int fd, const char __user *name); +asmlinkage long sys_getfsxattrat(int dfd, const char __user *filename, + struct fsxattr *fsx, unsigned int at_flags); +asmlinkage long sys_setfsxattrat(int dfd, const char __user *filename, + struct fsxattr *fsx, unsigned int at_flags); asmlinkage long sys_getcwd(char __user *buf, unsigned long size); asmlinkage long sys_eventfd2(unsigned int count, int flags); asmlinkage long sys_epoll_create1(int flags); diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 88dc393c2bca38c0fa1b3fae579f7cfe4931223c..50be2e1007bc2779120d05c6e9512a689f86779c 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -850,8 +850,14 @@ __SYSCALL(__NR_listxattrat, sys_listxattrat) #define __NR_removexattrat 466 __SYSCALL(__NR_removexattrat, sys_removexattrat) +/* fs/inode.c */ +#define __NR_getfsxattrat 467 +__SYSCALL(__NR_getfsxattrat, sys_getfsxattrat) +#define __NR_setfsxattrat 468 +__SYSCALL(__NR_setfsxattrat, sys_setfsxattrat) + #undef __NR_syscalls -#define __NR_syscalls 467 +#define __NR_syscalls 469 /* * 32 bit systems traditionally used different