lib/posix-fdio: Adopt fch* syscalls from vfscore

This change moves the implementation of the fchmod and fchown syscalls
from vfscore to posix-fdio, allowing shim operation on both ukfiles and
legacy vfscore files.
In addition, this move fixes a file ref leak in vfscore's fchmod due to
a missing fdrop after fd lookup.

Signed-off-by: Andrei Tatar <andrei@unikraft.io>
Approved-by: Sergiu Moga <sergiu@unikraft.io>
Reviewed-by: Sergiu Moga <sergiu@unikraft.io>
GitHub-Closes: #1581

diff --git a/lib/posix-fdio/Makefile.uk b/lib/posix-fdio/Makefile.uk
index ec299602d93b6cac1bdbc3aa08a5fe5078b3c693..0fd0b12e477ec894029f70cea4aa06a94bf12d98 100644 (file)
--- a/lib/posix-fdio/Makefile.uk
+++ b/lib/posix-fdio/Makefile.uk
@@ -22,6 +22,8 @@ UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += write-3
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += lseek-3
 
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += fstat-2
+UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += fchmod-2
+UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += fchown-3
 
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += fsync-1
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBPOSIX_FDIO) += fdatasync-1

diff --git a/lib/posix-fdio/fd-shim.c b/lib/posix-fdio/fd-shim.c
index 1bb008d34fba5ab2689cde5d51aa57e8195afcef..7fb073308772db3b450ca6ff499e20b012c8078c 100644 (file)
--- a/lib/posix-fdio/fd-shim.c
+++ b/lib/posix-fdio/fd-shim.c
@@ -322,6 +322,52 @@ UK_SYSCALL_R_DEFINE(int, fstat, int, fd, struct stat *, statbuf)
        return r;
 }
 
+UK_SYSCALL_R_DEFINE(int, fchmod, int, fd, mode_t, mode)
+{
+       int r;
+       union uk_shim_file sf;
+
+       switch (uk_fdtab_shim_get(fd, &sf)) {
+       case UK_SHIM_OFILE:
+               r = uk_sys_fchmod(sf.ofile, mode);
+               uk_fdtab_ret(sf.ofile);
+               break;
+#if CONFIG_LIBVFSCORE
+       case UK_SHIM_LEGACY:
+               /* vfscore_fchmod returns positive error codes */
+               r = -vfscore_fchmod(sf.vfile, mode);
+               fdrop(sf.vfile);
+               break;
+#endif /* CONFIG_LIBVFSCORE */
+       default:
+               r = -EBADF;
+       }
+       return r;
+}
+
+UK_SYSCALL_R_DEFINE(int, fchown, int, fd, uid_t, owner, gid_t, group)
+{
+       int r;
+       union uk_shim_file sf;
+
+       switch (uk_fdtab_shim_get(fd, &sf)) {
+       case UK_SHIM_OFILE:
+               r = uk_sys_fchown(sf.ofile, owner, group);
+               uk_fdtab_ret(sf.ofile);
+               break;
+#if CONFIG_LIBVFSCORE
+       case UK_SHIM_LEGACY:
+               /* vfscore does not support fchown; stub out */
+               fdrop(sf.vfile);
+               r = 0;
+               break;
+#endif /* CONFIG_LIBVFSCORE */
+       default:
+               r = -EBADF;
+       }
+       return r;
+}
+
 /* Ctl */
 
 UK_SYSCALL_R_DEFINE(int, fsync, int, fd)

diff --git a/lib/vfscore/Makefile.uk b/lib/vfscore/Makefile.uk
index 0165d7ed3825114a34ac5c5ec67a4c8b0f93ae78..85f8475b8ece62555fe2ce6b08a6e79f25783e92 100644 (file)
--- a/lib/vfscore/Makefile.uk
+++ b/lib/vfscore/Makefile.uk
@@ -32,7 +32,6 @@ UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += faccessat-4
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += chdir-1
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += fchdir-1
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += chmod-2
-UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += fchmod-2
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += utime-2
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += utimes-2
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += mknod-3
@@ -49,7 +48,6 @@ UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += sync-0
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += mount-5
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += statfs-2
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += fstatfs-2
-UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += fchown-3
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += lchown-3
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += chown-3
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += stat-2

diff --git a/lib/vfscore/exportsyms.uk b/lib/vfscore/exportsyms.uk
index 2b045078bc7e1c96aa31ab109847a95375d1c5dc..87ba23a094282c593000a6bc9404ab1e39c5b52a 100644 (file)
--- a/lib/vfscore/exportsyms.uk
+++ b/lib/vfscore/exportsyms.uk
@@ -48,12 +48,6 @@ uk_syscall_r_stat
 chmod
 uk_syscall_e_chmod
 uk_syscall_r_chmod
-fchmod
-uk_syscall_e_fchmod
-uk_syscall_r_fchmod
-fchown
-uk_syscall_e_fchown
-uk_syscall_r_fchown
 dup
 uk_syscall_e_dup
 uk_syscall_r_dup
@@ -264,5 +258,6 @@ vfscore_fsync
 vfscore_ftruncate
 vfscore_fallocate
 vfscore_fstat
+vfscore_fchmod
 vfscore_fcntl
 vfscore_ioctl

diff --git a/lib/vfscore/include/vfscore/syscalls.h b/lib/vfscore/include/vfscore/syscalls.h
index 3b7766b53a874a1ead50e48e4e57042c6368b8de..0467fff0ebb042173350e5423e183df4167327ff 100644 (file)
--- a/lib/vfscore/include/vfscore/syscalls.h
+++ b/lib/vfscore/include/vfscore/syscalls.h
@@ -29,6 +29,7 @@ ssize_t vfscore_write(struct vfscore_file *fp, const void *buf, size_t count);
 int vfscore_lseek(struct vfscore_file *fp, off_t off, int type, off_t *origin);
 
 int vfscore_fstat(struct vfscore_file *fp, struct stat *st);
+int vfscore_fchmod(struct vfscore_file *fp, mode_t mode);
 
 int vfscore_fsync(struct vfscore_file *fp);
 

diff --git a/lib/vfscore/main.c b/lib/vfscore/main.c
index 4e72dbab6f99b3319ad4c26c52614d6cb3b58d1b..bee76756a15c532da3cc7c28efa61dcd3116403f 100644 (file)
--- a/lib/vfscore/main.c
+++ b/lib/vfscore/main.c
@@ -2363,32 +2363,6 @@ out_error:
        return -error;
 }
 
-UK_TRACEPOINT(trace_vfs_fchmod, "\"%d\" 0%0o", int, mode_t);
-UK_TRACEPOINT(trace_vfs_fchmod_ret, "");
-
-UK_SYSCALL_R_DEFINE(int, fchmod, int, fd, mode_t, mode)
-{
-       trace_vfs_fchmod(fd, mode);
-       int error = sys_fchmod(fd, mode & UK_ALLPERMS);
-       trace_vfs_fchmod_ret();
-       if (error) {
-               return -error;
-       }
-
-       return 0;
-}
-
-UK_TRACEPOINT(trace_vfs_fchown, "\"%d\" %d %d", int, uid_t, gid_t);
-UK_TRACEPOINT(trace_vfs_fchown_ret, "");
-
-UK_SYSCALL_R_DEFINE(int, fchown, int, fd, uid_t, owner, gid_t, group)
-{
-       trace_vfs_fchown(fd, owner, group);
-       UK_WARN_STUBBED();
-       trace_vfs_fchown_ret();
-       return 0;
-}
-
 UK_SYSCALL_R_DEFINE(int, chown, const char*, path, uid_t, owner, gid_t, group)
 {
        UK_WARN_STUBBED();

diff --git a/lib/vfscore/syscalls.c b/lib/vfscore/syscalls.c
index e72df7f1dc0cc80ed5815a9c60c7db95e22d2930..5b6e2570b1db3256c0877ed5b308b9ea3fc0d65a 100644 (file)
--- a/lib/vfscore/syscalls.c
+++ b/lib/vfscore/syscalls.c
@@ -1570,11 +1570,8 @@ sys_chmod(const char *path, mode_t mode)
 }
 
 int
-sys_fchmod(int fd, mode_t mode)
+vfscore_fchmod(struct vfscore_file *f, mode_t mode)
 {
-       struct vfscore_file *f = vfscore_get_file(fd);
-       if (!f)
-               return EBADF;
        // Posix is ambivalent on what fchmod() should do on an fd that does not
        // refer to a real file. It suggests an implementation may (but not must)
        // fail EINVAL on a pipe, can behave in an "unspecified" manner on a
@@ -1586,6 +1583,6 @@ sys_fchmod(int fd, mode_t mode)
        if (f->f_dentry->d_mount->m_flags & MNT_RDONLY) {
                return EROFS;
        } else {
-               return vn_setmode(f->f_dentry->d_vnode, mode);
+               return vn_setmode(f->f_dentry->d_vnode, mode & UK_ALLPERMS);
        }
 }

diff --git a/lib/vfscore/vfs.h b/lib/vfscore/vfs.h
index b726b20bb43bca3e2396b41c24e52670afeedff6..c4db5ac02200fa0b67f68770cdbabec738649d17 100644 (file)
--- a/lib/vfscore/vfs.h
+++ b/lib/vfscore/vfs.h
@@ -517,19 +517,6 @@ void sync(void);
  */
 int    sys_chmod(const char *path, mode_t mode);
 
-/**
- * Changes mode of the file specified by the open file descriptor fd.
- *
- * @param fd
- *     An open file descriptor
- * @param mode
- *     The new file mode
- * @return
- *     - (0):  Completed successfully
- *     - (<0): Negative value with error code
- */
-int sys_fchmod(int fd, mode_t mode);
-
 /**
  * Converts to full path from the cwd of task and path.
  *