diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c index d3679be42b83..9f336748fbdb 100644 --- a/sys/kern/vfs_lookup.c +++ b/sys/kern/vfs_lookup.c @@ -410,6 +410,7 @@ namei(struct nameidata *ndp) dp = NULL; cnp->cn_nameptr = cnp->cn_pnbuf; if (cnp->cn_pnbuf[0] == '/') { + ndp->ni_resflags |= NIRES_ABS; error = namei_handle_root(ndp, &dp); } else { if (ndp->ni_startdir != NULL) { @@ -1302,6 +1303,7 @@ NDINIT_ALL(struct nameidata *ndp, u_long op, u_long flags, enum uio_seg segflg, ndp->ni_dirp = namep; ndp->ni_dirfd = dirfd; ndp->ni_startdir = startdir; + ndp->ni_resflags = 0; filecaps_init(&ndp->ni_filecaps); ndp->ni_cnd.cn_thread = td; if (rightsp != NULL) diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c index b19dd67b5cca..ef01081601f2 100644 --- a/sys/kern/vfs_syscalls.c +++ b/sys/kern/vfs_syscalls.c @@ -3544,10 +3544,10 @@ kern_renameat(struct thread *td, int oldfd, const char *old, int newfd, goto out; } #ifdef CAPABILITIES - if (newfd != AT_FDCWD) { + if (newfd != AT_FDCWD && (tond.ni_resflags & NIRES_ABS) == 0) { /* * If the target already exists we require CAP_UNLINKAT - * from 'newfd'. + * from 'newfd', when newfd was used for the lookup. */ error = cap_check(&tond.ni_filecaps.fc_rights, &cap_unlinkat_rights); diff --git a/sys/sys/namei.h b/sys/sys/namei.h index bec6ef3a48ef..bd5198bd936f 100644 --- a/sys/sys/namei.h +++ b/sys/sys/namei.h @@ -87,6 +87,10 @@ struct nameidata { */ struct vnode *ni_vp; /* vnode of result */ struct vnode *ni_dvp; /* vnode of intermediate directory */ + /* + * Results: flags returned from namei + */ + u_int ni_resflags; /* * Shared between namei and lookup/commit routines. */ @@ -159,6 +163,11 @@ struct nameidata { #define NOCAPCHECK 0x20000000 /* do not perform capability checks */ #define PARAMASK 0x3ffffe00 /* mask of parameter descriptors */ +/* + * Namei results flags + */ +#define NIRES_ABS 0x00000001 /* Path was absolute */ + /* * Flags in ni_lcf, valid for the duration of the namei call. */