The branch stable/13 has been updated by rmacklem: URL: https://cgit.FreeBSD.org/src/commit/?id=7aaf39f6b3b0bc5cc171eac7ca118d17460ea5db
commit 7aaf39f6b3b0bc5cc171eac7ca118d17460ea5db Author: Rick Macklem <[email protected]> AuthorDate: 2023-11-23 15:23:33 +0000 Commit: Rick Macklem <[email protected]> CommitDate: 2023-11-30 12:28:50 +0000 nfsd: Fix NFS access to .zfs/snapshot snapshots When a process attempts to access a snapshot under /<dataset>/.zfs/snapshot, the snapshot is automounted. However, without this patch, the automount does not set mnt_exjail, which results in the snapshot not being accessible over NFS. This patch defines a new function called vfs_exjail_clone() which sets mnt_exjail from another mount point and then uses that function to set mnt_exjail in the snapshot automount. A separate patch that is currently a pull request for OpenZFS, calls this function to fix the problem. PR: 275200 (cherry picked from commit f5f277728adec4c5b3e840a1fb16bd16f8cc956d) --- sys/kern/vfs_mount.c | 35 +++++++++++++++++++++++++++++++++++ sys/sys/mount.h | 4 ++++ 2 files changed, 39 insertions(+) diff --git a/sys/kern/vfs_mount.c b/sys/kern/vfs_mount.c index 4597ae09a831..cefadf75a3a8 100644 --- a/sys/kern/vfs_mount.c +++ b/sys/kern/vfs_mount.c @@ -2824,6 +2824,41 @@ suspend_all_fs(void) mtx_unlock(&mountlist_mtx); } +/* + * Clone the mnt_exjail field to a new mount point. + */ +void +vfs_exjail_clone(struct mount *inmp, struct mount *outmp) +{ + struct ucred *cr; + struct prison *pr; + + MNT_ILOCK(inmp); + cr = inmp->mnt_exjail; + if (cr != NULL) { + crhold(cr); + MNT_IUNLOCK(inmp); + pr = cr->cr_prison; + sx_slock(&allprison_lock); + if (!prison_isalive(pr)) { + sx_sunlock(&allprison_lock); + crfree(cr); + return; + } + MNT_ILOCK(outmp); + if (outmp->mnt_exjail == NULL) { + outmp->mnt_exjail = cr; + atomic_add_int(&pr->pr_exportcnt, 1); + cr = NULL; + } + MNT_IUNLOCK(outmp); + sx_sunlock(&allprison_lock); + if (cr != NULL) + crfree(cr); + } else + MNT_IUNLOCK(inmp); +} + void resume_all_fs(void) { diff --git a/sys/sys/mount.h b/sys/sys/mount.h index 2d9ee8d78bdd..9c1862956812 100644 --- a/sys/sys/mount.h +++ b/sys/sys/mount.h @@ -947,6 +947,9 @@ vfs_statfs_t __vfs_statfs; * exported vnode operations */ +/* Define this to indicate that vfs_exjail_clone() exists for ZFS to use. */ +#define VFS_SUPPORTS_EXJAIL_CLONE 1 + int dounmount(struct mount *, int, struct thread *); int kernel_mount(struct mntarg *ma, uint64_t flags); @@ -984,6 +987,7 @@ int vfs_setpublicfs /* set publicly exported fs */ (struct mount *, struct netexport *, struct export_args *); void vfs_periodic(struct mount *, int); int vfs_busy(struct mount *, int); +void vfs_exjail_clone(struct mount *, struct mount *); int vfs_export /* process mount export info */ (struct mount *, struct export_args *, int); void vfs_free_addrlist(struct netexport *);
