diff options
| -rw-r--r-- | sys/kern/vfs_cache.c | 16 | ||||
| -rw-r--r-- | sys/kern/vfs_lookup.c | 33 | ||||
| -rw-r--r-- | sys/kern/vfs_syscalls.c | 18 | ||||
| -rw-r--r-- | sys/sys/namei.h | 2 |
4 files changed, 48 insertions, 21 deletions
diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c index 22dfe01ac624..c9bc2074d5e6 100644 --- a/sys/kern/vfs_cache.c +++ b/sys/kern/vfs_cache.c @@ -3736,8 +3736,8 @@ cache_fpl_terminated(struct cache_fpl *fpl) #define CACHE_FPL_SUPPORTED_CN_FLAGS \ (NC_NOMAKEENTRY | NC_KEEPPOSENTRY | LOCKLEAF | LOCKPARENT | WANTPARENT | \ - FOLLOW | LOCKSHARED | SAVENAME | SAVESTART | WILLBEDIR | ISOPEN | \ - NOMACCHECK | AUDITVNODE1 | AUDITVNODE2 | NOCAPCHECK) + FAILIFEXISTS | FOLLOW | LOCKSHARED | SAVENAME | SAVESTART | WILLBEDIR | \ + ISOPEN | NOMACCHECK | AUDITVNODE1 | AUDITVNODE2 | NOCAPCHECK) #define CACHE_FPL_INTERNAL_CN_FLAGS \ (ISDOTDOT | MAKEENTRY | ISLASTCN) @@ -3990,6 +3990,11 @@ cache_fplookup_final_modifying(struct cache_fpl *fpl) return (cache_fpl_handled(fpl, EROFS)); } + if (fpl->tvp != NULL && (cnp->cn_flags & FAILIFEXISTS) != 0) { + cache_fpl_smr_exit(fpl); + return (cache_fpl_handled(fpl, EEXIST)); + } + /* * Secure access to dvp; check cache_fplookup_partial_setup for * reasoning. @@ -4070,6 +4075,12 @@ cache_fplookup_final_modifying(struct cache_fpl *fpl) return (cache_fpl_aborted(fpl)); } + if ((cnp->cn_flags & FAILIFEXISTS) != 0) { + vput(dvp); + vput(tvp); + return (cache_fpl_handled(fpl, EEXIST)); + } + if ((cnp->cn_flags & LOCKLEAF) == 0) { VOP_UNLOCK(tvp); } @@ -4221,6 +4232,7 @@ cache_fplookup_noentry(struct cache_fpl *fpl) MPASS(!cache_fpl_isdotdot(cnp)); if (cnp->cn_nameiop != LOOKUP) { + fpl->tvp = NULL; return (cache_fplookup_modifying(fpl)); } diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c index 511efaa9d01a..da04dd09af40 100644 --- a/sys/kern/vfs_lookup.c +++ b/sys/kern/vfs_lookup.c @@ -545,6 +545,16 @@ namei(struct nameidata *ndp) ndp->ni_debugflags |= NAMEI_DBG_CALLED; if (ndp->ni_startdir != NULL) ndp->ni_debugflags |= NAMEI_DBG_HADSTARTDIR; + if (cnp->cn_flags & FAILIFEXISTS) { + KASSERT(cnp->cn_nameiop == CREATE, + ("%s: FAILIFEXISTS passed for op %d", __func__, cnp->cn_nameiop)); + /* + * The limitation below is to restrict hairy corner cases. + */ + KASSERT((cnp->cn_flags & (LOCKPARENT | LOCKLEAF)) == LOCKPARENT, + ("%s: FAILIFEXISTS must be passed with LOCKPARENT and without LOCKLEAF", + __func__)); + } /* * For NDVALIDATE. * @@ -1295,8 +1305,11 @@ success: goto bad2; } } - if (ndp->ni_vp != NULL && ndp->ni_vp->v_type == VDIR) + if (ndp->ni_vp != NULL) { nameicap_tracker_add(ndp, ndp->ni_vp); + if ((cnp->cn_flags & (FAILIFEXISTS | ISSYMLINK)) == FAILIFEXISTS) + goto bad_eexist; + } return (0); bad2: @@ -1311,6 +1324,24 @@ bad: vput(dp); ndp->ni_vp = NULL; return (error); +bad_eexist: + /* + * FAILIFEXISTS handling. + * + * XXX namei called with LOCKPARENT but not LOCKLEAF has the strange + * behaviour of leaving the vnode unlocked if the target is the same + * vnode as the parent. + */ + MPASS((cnp->cn_flags & ISSYMLINK) == 0); + if (ndp->ni_vp == ndp->ni_dvp) + vrele(ndp->ni_dvp); + else + vput(ndp->ni_dvp); + vrele(ndp->ni_vp); + ndp->ni_dvp = NULL; + ndp->ni_vp = NULL; + NDFREE(ndp, NDF_ONLY_PNBUF); + return (EEXIST); } /* diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c index cbfff229540a..5a30b06e4e9e 100644 --- a/sys/kern/vfs_syscalls.c +++ b/sys/kern/vfs_syscalls.c @@ -3768,7 +3768,6 @@ kern_mkdirat(struct thread *td, int fd, const char *path, enum uio_seg segflg, int mode) { struct mount *mp; - struct vnode *vp; struct vattr vattr; struct nameidata nd; int error; @@ -3777,26 +3776,11 @@ kern_mkdirat(struct thread *td, int fd, const char *path, enum uio_seg segflg, restart: bwillwrite(); NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1 | - NC_NOMAKEENTRY | NC_KEEPPOSENTRY, segflg, path, fd, + NC_NOMAKEENTRY | NC_KEEPPOSENTRY | FAILIFEXISTS, segflg, path, fd, &cap_mkdirat_rights, td); nd.ni_cnd.cn_flags |= WILLBEDIR; if ((error = namei(&nd)) != 0) return (error); - vp = nd.ni_vp; - if (vp != NULL) { - NDFREE(&nd, NDF_ONLY_PNBUF); - /* - * XXX namei called with LOCKPARENT but not LOCKLEAF has - * the strange behaviour of leaving the vnode unlocked - * if the target is the same vnode as the parent. - */ - if (vp == nd.ni_dvp) - vrele(nd.ni_dvp); - else - vput(nd.ni_dvp); - vrele(vp); - return (EEXIST); - } if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) { NDFREE(&nd, NDF_ONLY_PNBUF); vput(nd.ni_dvp); diff --git a/sys/sys/namei.h b/sys/sys/namei.h index dfb5e5e4cec3..ddba9cbd8912 100644 --- a/sys/sys/namei.h +++ b/sys/sys/namei.h @@ -143,7 +143,7 @@ int cache_fplookup(struct nameidata *ndp, enum cache_fpl_status *status, #define LOCKLEAF 0x0004 /* lock vnode on return */ #define LOCKPARENT 0x0008 /* want parent vnode returned locked */ #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */ -/* UNUSED 0x0020 */ +#define FAILIFEXISTS 0x0020 /* return EEXIST if found */ #define FOLLOW 0x0040 /* follow symbolic links */ #define BENEATH 0x0080 /* No escape from the start dir */ #define LOCKSHARED 0x0100 /* Shared lock leaf */ |