From ab8e4aee0a3f73d1b12e6d63b42075f0586ad4fd Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Sat, 2 Feb 2013 05:18:08 -0800 Subject: [PATCH] nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion In struct nfs4_ace remove the member who and replace it with an anonymous union holding who_uid and who_gid. Allowing typesafe storage uids and gids. Add a helper pace_gt for sorting posix_acl_entries. In struct posix_user_ace_state to replace uid with a union of kuid_t uid and kgid_t gid. Remove all initializations of the deprecated posic_acl_entry e_id field. Which is not present when user namespaces are enabled. Split find_uid into two functions find_uid and find_gid that work in a typesafe manner. In nfs4xdr update nfsd4_encode_fattr to deal with the changes in struct nfs4_ace. Rewrite nfsd4_encode_name to take a kuid_t and a kgid_t instead of a generic id and flag if it is a group or a uid. Replace the group flag with a test for a valid gid. Modify nfsd4_encode_user to take a kuid_t and call the modifed nfsd4_encode_name. Modify nfsd4_encode_group to take a kgid_t and call the modified nfsd4_encode_name. Modify nfsd4_encode_aclname to take an ace instead of taking the fields of an ace broken out. This allows it to detect if the ace is for a user or a group and to pass the appropriate value while still being typesafe. Cc: "J. Bruce Fields" Cc: Trond Myklebust Signed-off-by: "Eric W. Biederman" --- fs/nfsd/nfs4acl.c | 63 ++++++++++++++++++++++++++++++++------------ fs/nfsd/nfs4xdr.c | 41 +++++++++++++++++----------- include/linux/nfs4.h | 6 ++++- 3 files changed, 76 insertions(+), 34 deletions(-) diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c index 9c51aff02ae2..8a50b3c18093 100644 --- a/fs/nfsd/nfs4acl.c +++ b/fs/nfsd/nfs4acl.c @@ -264,7 +264,7 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, ace->flag = eflag; ace->access_mask = deny_mask_from_posix(deny, flags); ace->whotype = NFS4_ACL_WHO_NAMED; - ace->who = pa->e_id; + ace->who_uid = pa->e_uid; ace++; acl->naces++; } @@ -273,7 +273,7 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, flags); ace->whotype = NFS4_ACL_WHO_NAMED; - ace->who = pa->e_id; + ace->who_uid = pa->e_uid; ace++; acl->naces++; pa++; @@ -300,7 +300,7 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, flags); ace->whotype = NFS4_ACL_WHO_NAMED; - ace->who = pa->e_id; + ace->who_gid = pa->e_gid; ace++; acl->naces++; pa++; @@ -329,7 +329,7 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; ace->access_mask = deny_mask_from_posix(deny, flags); ace->whotype = NFS4_ACL_WHO_NAMED; - ace->who = pa->e_id; + ace->who_gid = pa->e_gid; ace++; acl->naces++; } @@ -345,6 +345,18 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, acl->naces++; } +static bool +pace_gt(struct posix_acl_entry *pace1, struct posix_acl_entry *pace2) +{ + if (pace1->e_tag != pace2->e_tag) + return pace1->e_tag > pace2->e_tag; + if (pace1->e_tag == ACL_USER) + return uid_gt(pace1->e_uid, pace2->e_uid); + if (pace1->e_tag == ACL_GROUP) + return gid_gt(pace1->e_gid, pace2->e_gid); + return false; +} + static void sort_pacl_range(struct posix_acl *pacl, int start, int end) { int sorted = 0, i; @@ -355,8 +367,8 @@ sort_pacl_range(struct posix_acl *pacl, int start, int end) { while (!sorted) { sorted = 1; for (i = start; i < end; i++) { - if (pacl->a_entries[i].e_id - > pacl->a_entries[i+1].e_id) { + if (pace_gt(&pacl->a_entries[i], + &pacl->a_entries[i+1])) { sorted = 0; tmp = pacl->a_entries[i]; pacl->a_entries[i] = pacl->a_entries[i+1]; @@ -398,7 +410,10 @@ struct posix_ace_state { }; struct posix_user_ace_state { - uid_t uid; + union { + kuid_t uid; + kgid_t gid; + }; struct posix_ace_state perms; }; @@ -521,7 +536,6 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) if (error) goto out_err; low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags); - pace->e_id = ACL_UNDEFINED_ID; for (i=0; i < state->users->n; i++) { pace++; @@ -531,7 +545,7 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) goto out_err; low_mode_from_nfs4(state->users->aces[i].perms.allow, &pace->e_perm, flags); - pace->e_id = state->users->aces[i].uid; + pace->e_uid = state->users->aces[i].uid; add_to_mask(state, &state->users->aces[i].perms); } @@ -541,7 +555,6 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) if (error) goto out_err; low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags); - pace->e_id = ACL_UNDEFINED_ID; add_to_mask(state, &state->group); for (i=0; i < state->groups->n; i++) { @@ -552,14 +565,13 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) goto out_err; low_mode_from_nfs4(state->groups->aces[i].perms.allow, &pace->e_perm, flags); - pace->e_id = state->groups->aces[i].uid; + pace->e_gid = state->groups->aces[i].gid; add_to_mask(state, &state->groups->aces[i].perms); } pace++; pace->e_tag = ACL_MASK; low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags); - pace->e_id = ACL_UNDEFINED_ID; pace++; pace->e_tag = ACL_OTHER; @@ -567,7 +579,6 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) if (error) goto out_err; low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags); - pace->e_id = ACL_UNDEFINED_ID; return pacl; out_err: @@ -587,12 +598,13 @@ static inline void deny_bits(struct posix_ace_state *astate, u32 mask) astate->deny |= mask & ~astate->allow; } -static int find_uid(struct posix_acl_state *state, struct posix_ace_state_array *a, uid_t uid) +static int find_uid(struct posix_acl_state *state, kuid_t uid) { + struct posix_ace_state_array *a = state->users; int i; for (i = 0; i < a->n; i++) - if (a->aces[i].uid == uid) + if (uid_eq(a->aces[i].uid, uid)) return i; /* Not found: */ a->n++; @@ -603,6 +615,23 @@ static int find_uid(struct posix_acl_state *state, struct posix_ace_state_array return i; } +static int find_gid(struct posix_acl_state *state, kgid_t gid) +{ + struct posix_ace_state_array *a = state->groups; + int i; + + for (i = 0; i < a->n; i++) + if (gid_eq(a->aces[i].gid, gid)) + return i; + /* Not found: */ + a->n++; + a->aces[i].gid = gid; + a->aces[i].perms.allow = state->everyone.allow; + a->aces[i].perms.deny = state->everyone.deny; + + return i; +} + static void deny_bits_array(struct posix_ace_state_array *a, u32 mask) { int i; @@ -636,7 +665,7 @@ static void process_one_v4_ace(struct posix_acl_state *state, } break; case ACL_USER: - i = find_uid(state, state->users, ace->who); + i = find_uid(state, ace->who_uid); if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { allow_bits(&state->users->aces[i].perms, mask); } else { @@ -658,7 +687,7 @@ static void process_one_v4_ace(struct posix_acl_state *state, } break; case ACL_GROUP: - i = find_uid(state, state->groups, ace->who); + i = find_gid(state, ace->who_gid); if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { allow_bits(&state->groups->aces[i].perms, mask); } else { diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 0dc11586682f..3812b06d24b1 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -293,13 +293,13 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval, ace->whotype = nfs4_acl_get_whotype(buf, dummy32); status = nfs_ok; if (ace->whotype != NFS4_ACL_WHO_NAMED) - ace->who = 0; + ; else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP) status = nfsd_map_name_to_gid(argp->rqstp, - buf, dummy32, &ace->who); + buf, dummy32, &ace->who_gid); else status = nfsd_map_name_to_uid(argp->rqstp, - buf, dummy32, &ace->who); + buf, dummy32, &ace->who_uid); if (status) return status; } @@ -1926,7 +1926,7 @@ static u32 nfs4_file_type(umode_t mode) } static __be32 -nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, uid_t id, int group, +nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, kuid_t uid, kgid_t gid, __be32 **p, int *buflen) { int status; @@ -1935,10 +1935,10 @@ nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, uid_t id, int group, return nfserr_resource; if (whotype != NFS4_ACL_WHO_NAMED) status = nfs4_acl_write_who(whotype, (u8 *)(*p + 1)); - else if (group) - status = nfsd_map_gid_to_name(rqstp, id, (u8 *)(*p + 1)); + else if (gid_valid(gid)) + status = nfsd_map_gid_to_name(rqstp, gid, (u8 *)(*p + 1)); else - status = nfsd_map_uid_to_name(rqstp, id, (u8 *)(*p + 1)); + status = nfsd_map_uid_to_name(rqstp, uid, (u8 *)(*p + 1)); if (status < 0) return nfserrno(status); *p = xdr_encode_opaque(*p, NULL, status); @@ -1948,22 +1948,33 @@ nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, uid_t id, int group, } static inline __be32 -nfsd4_encode_user(struct svc_rqst *rqstp, uid_t uid, __be32 **p, int *buflen) +nfsd4_encode_user(struct svc_rqst *rqstp, kuid_t user, __be32 **p, int *buflen) { - return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, uid, 0, p, buflen); + return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, user, INVALID_GID, + p, buflen); } static inline __be32 -nfsd4_encode_group(struct svc_rqst *rqstp, uid_t gid, __be32 **p, int *buflen) +nfsd4_encode_group(struct svc_rqst *rqstp, kgid_t group, __be32 **p, int *buflen) { - return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, gid, 1, p, buflen); + return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, INVALID_UID, group, + p, buflen); } static inline __be32 -nfsd4_encode_aclname(struct svc_rqst *rqstp, int whotype, uid_t id, int group, +nfsd4_encode_aclname(struct svc_rqst *rqstp, struct nfs4_ace *ace, __be32 **p, int *buflen) { - return nfsd4_encode_name(rqstp, whotype, id, group, p, buflen); + kuid_t uid = INVALID_UID; + kgid_t gid = INVALID_GID; + + if (ace->whotype == NFS4_ACL_WHO_NAMED) { + if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP) + gid = ace->who_gid; + else + uid = ace->who_uid; + } + return nfsd4_encode_name(rqstp, ace->whotype, uid, gid, p, buflen); } #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \ @@ -2224,9 +2235,7 @@ nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp, WRITE32(ace->type); WRITE32(ace->flag); WRITE32(ace->access_mask & NFS4_ACE_MASK_ALL); - status = nfsd4_encode_aclname(rqstp, ace->whotype, - ace->who, ace->flag & NFS4_ACE_IDENTIFIER_GROUP, - &p, &buflen); + status = nfsd4_encode_aclname(rqstp, ace, &p, &buflen); if (status == nfserr_resource) goto out_resource; if (status) diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h index e111fa419a4e..7b8fc73810ad 100644 --- a/include/linux/nfs4.h +++ b/include/linux/nfs4.h @@ -13,6 +13,7 @@ #define _LINUX_NFS4_H #include +#include #include struct nfs4_ace { @@ -20,7 +21,10 @@ struct nfs4_ace { uint32_t flag; uint32_t access_mask; int whotype; - uid_t who; + union { + kuid_t who_uid; + kgid_t who_gid; + }; }; struct nfs4_acl {