diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-27 12:01:58 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-27 12:01:58 -0800 |
commit | fb2a624d5fe8b9206d14bff52da7a368a3a8374c (patch) | |
tree | 634271fdc71329712acc0b95c21209b132409bac /security/selinux/ss | |
parent | 047ce6d380e8e66cfb6cbc22e873af89dd0c216c (diff) | |
parent | ee1a84fdfeedfd7362e9a8a8f15fedc3482ade2d (diff) |
Merge tag 'selinux-pr-20181224' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux patches from Paul Moore:
"I already used my best holiday pull request lines in the audit pull
request, so this one is going to be a bit more boring, sorry about
that. To make up for this, we do have a birthday of sorts to
celebrate: SELinux turns 18 years old this December. Perhaps not the
most exciting thing in the world for most people, but I think it's
safe to say that anyone reading this email doesn't exactly fall into
the "most people" category.
Back to business and the pull request itself:
Ondrej has five patches in this pull request and I lump them into
three categories: one patch to always allow submounts (using similar
logic to elsewhere in the kernel), one to fix some issues with the
SELinux policydb, and the others to cleanup and improve the SELinux
sidtab.
The other patches from Alexey and Petr and trivial fixes that are
adequately described in their respective subject lines.
With this last pull request of the year, I want to thank everyone who
has contributed patches, testing, and reviews to the SELinux project
this year, and the past 18 years. Like any good open source effort,
SELinux is only as good as the community which supports it, and I'm
very happy that we have the community we do - thank you all!"
* tag 'selinux-pr-20181224' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: overhaul sidtab to fix bug and improve performance
selinux: use separate table for initial SID lookup
selinux: make "selinux_policycap_names[]" const char *
selinux: always allow mounting submounts
selinux: refactor sidtab conversion
Documentation: Update SELinux reference policy URL
selinux: policydb - fix byte order and alignment issues
Diffstat (limited to 'security/selinux/ss')
-rw-r--r-- | security/selinux/ss/mls.c | 24 | ||||
-rw-r--r-- | security/selinux/ss/mls.h | 3 | ||||
-rw-r--r-- | security/selinux/ss/policydb.c | 61 | ||||
-rw-r--r-- | security/selinux/ss/services.c | 222 | ||||
-rw-r--r-- | security/selinux/ss/services.h | 2 | ||||
-rw-r--r-- | security/selinux/ss/sidtab.c | 609 | ||||
-rw-r--r-- | security/selinux/ss/sidtab.h | 96 |
7 files changed, 623 insertions, 394 deletions
diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index b7efa2296969..5e05f5b902d7 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -440,16 +440,17 @@ int mls_setup_user_range(struct policydb *p, /* * Convert the MLS fields in the security context - * structure `c' from the values specified in the - * policy `oldp' to the values specified in the policy `newp'. + * structure `oldc' from the values specified in the + * policy `oldp' to the values specified in the policy `newp', + * storing the resulting context in `newc'. */ int mls_convert_context(struct policydb *oldp, struct policydb *newp, - struct context *c) + struct context *oldc, + struct context *newc) { struct level_datum *levdatum; struct cat_datum *catdatum; - struct ebitmap bitmap; struct ebitmap_node *node; int l, i; @@ -459,28 +460,25 @@ int mls_convert_context(struct policydb *oldp, for (l = 0; l < 2; l++) { levdatum = hashtab_search(newp->p_levels.table, sym_name(oldp, SYM_LEVELS, - c->range.level[l].sens - 1)); + oldc->range.level[l].sens - 1)); if (!levdatum) return -EINVAL; - c->range.level[l].sens = levdatum->level->sens; + newc->range.level[l].sens = levdatum->level->sens; - ebitmap_init(&bitmap); - ebitmap_for_each_positive_bit(&c->range.level[l].cat, node, i) { + ebitmap_for_each_positive_bit(&oldc->range.level[l].cat, + node, i) { int rc; catdatum = hashtab_search(newp->p_cats.table, sym_name(oldp, SYM_CATS, i)); if (!catdatum) return -EINVAL; - rc = ebitmap_set_bit(&bitmap, catdatum->value - 1, 1); + rc = ebitmap_set_bit(&newc->range.level[l].cat, + catdatum->value - 1, 1); if (rc) return rc; - - cond_resched(); } - ebitmap_destroy(&c->range.level[l].cat); - c->range.level[l].cat = bitmap; } return 0; diff --git a/security/selinux/ss/mls.h b/security/selinux/ss/mls.h index 67093647576d..7954b1e60b64 100644 --- a/security/selinux/ss/mls.h +++ b/security/selinux/ss/mls.h @@ -46,7 +46,8 @@ int mls_range_set(struct context *context, struct mls_range *range); int mls_convert_context(struct policydb *oldp, struct policydb *newp, - struct context *context); + struct context *oldc, + struct context *newc); int mls_compute_sid(struct policydb *p, struct context *scontext, diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index f4eadd3f7350..a50d625e7946 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -909,13 +909,21 @@ int policydb_load_isids(struct policydb *p, struct sidtab *s) if (!c->context[0].user) { pr_err("SELinux: SID %s was never defined.\n", c->u.name); + sidtab_destroy(s); + goto out; + } + if (c->sid[0] == SECSID_NULL || c->sid[0] > SECINITSID_NUM) { + pr_err("SELinux: Initial SID %s out of range.\n", + c->u.name); + sidtab_destroy(s); goto out; } - rc = sidtab_insert(s, c->sid[0], &c->context[0]); + rc = sidtab_set_initial(s, c->sid[0], &c->context[0]); if (rc) { pr_err("SELinux: unable to load initial SID %s.\n", c->u.name); + sidtab_destroy(s); goto out; } } @@ -2108,6 +2116,7 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info, { int i, j, rc; u32 nel, len; + __be64 prefixbuf[1]; __le32 buf[3]; struct ocontext *l, *c; u32 nodebuf[8]; @@ -2217,21 +2226,30 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info, goto out; break; } - case OCON_IBPKEY: - rc = next_entry(nodebuf, fp, sizeof(u32) * 4); + case OCON_IBPKEY: { + u32 pkey_lo, pkey_hi; + + rc = next_entry(prefixbuf, fp, sizeof(u64)); + if (rc) + goto out; + + /* we need to have subnet_prefix in CPU order */ + c->u.ibpkey.subnet_prefix = be64_to_cpu(prefixbuf[0]); + + rc = next_entry(buf, fp, sizeof(u32) * 2); if (rc) goto out; - c->u.ibpkey.subnet_prefix = be64_to_cpu(*((__be64 *)nodebuf)); + pkey_lo = le32_to_cpu(buf[0]); + pkey_hi = le32_to_cpu(buf[1]); - if (nodebuf[2] > 0xffff || - nodebuf[3] > 0xffff) { + if (pkey_lo > U16_MAX || pkey_hi > U16_MAX) { rc = -EINVAL; goto out; } - c->u.ibpkey.low_pkey = le32_to_cpu(nodebuf[2]); - c->u.ibpkey.high_pkey = le32_to_cpu(nodebuf[3]); + c->u.ibpkey.low_pkey = pkey_lo; + c->u.ibpkey.high_pkey = pkey_hi; rc = context_read_and_validate(&c->context[0], p, @@ -2239,7 +2257,10 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info, if (rc) goto out; break; - case OCON_IBENDPORT: + } + case OCON_IBENDPORT: { + u32 port; + rc = next_entry(buf, fp, sizeof(u32) * 2); if (rc) goto out; @@ -2249,12 +2270,13 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info, if (rc) goto out; - if (buf[1] > 0xff || buf[1] == 0) { + port = le32_to_cpu(buf[1]); + if (port > U8_MAX || port == 0) { rc = -EINVAL; goto out; } - c->u.ibendport.port = le32_to_cpu(buf[1]); + c->u.ibendport.port = port; rc = context_read_and_validate(&c->context[0], p, @@ -2262,7 +2284,8 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info, if (rc) goto out; break; - } + } /* end case */ + } /* end switch */ } } rc = 0; @@ -3105,6 +3128,7 @@ static int ocontext_write(struct policydb *p, struct policydb_compat_info *info, { unsigned int i, j, rc; size_t nel, len; + __be64 prefixbuf[1]; __le32 buf[3]; u32 nodebuf[8]; struct ocontext *c; @@ -3192,12 +3216,17 @@ static int ocontext_write(struct policydb *p, struct policydb_compat_info *info, return rc; break; case OCON_IBPKEY: - *((__be64 *)nodebuf) = cpu_to_be64(c->u.ibpkey.subnet_prefix); + /* subnet_prefix is in CPU order */ + prefixbuf[0] = cpu_to_be64(c->u.ibpkey.subnet_prefix); - nodebuf[2] = cpu_to_le32(c->u.ibpkey.low_pkey); - nodebuf[3] = cpu_to_le32(c->u.ibpkey.high_pkey); + rc = put_entry(prefixbuf, sizeof(u64), 1, fp); + if (rc) + return rc; - rc = put_entry(nodebuf, sizeof(u32), 4, fp); + buf[0] = cpu_to_le32(c->u.ibpkey.low_pkey); + buf[1] = cpu_to_le32(c->u.ibpkey.high_pkey); + + rc = put_entry(buf, sizeof(u32), 2, fp); if (rc) return rc; rc = context_write(p, &c->context[0], fp); diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 12e414394530..dd44126c8d14 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -71,7 +71,7 @@ #include "audit.h" /* Policy capability names */ -char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = { +const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = { "network_peer_controls", "open_perms", "extended_socket_class", @@ -776,7 +776,7 @@ static int security_compute_validatetrans(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; if (!user) tclass = unmap_class(&state->ss->map, orig_tclass); @@ -876,7 +876,7 @@ int security_bounded_transition(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; rc = -EINVAL; old_context = sidtab_search(sidtab, old_sid); @@ -1034,7 +1034,7 @@ void security_compute_xperms_decision(struct selinux_state *state, goto allow; policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1123,7 +1123,7 @@ void security_compute_av(struct selinux_state *state, goto allow; policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1177,7 +1177,7 @@ void security_compute_av_user(struct selinux_state *state, goto allow; policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1315,7 +1315,7 @@ static int security_sid_to_context_core(struct selinux_state *state, } read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; if (force) context = sidtab_search_force(sidtab, sid); else @@ -1483,7 +1483,7 @@ static int security_context_to_sid_core(struct selinux_state *state, } read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; rc = string_to_context_struct(policydb, sidtab, scontext2, &context, def_sid); if (rc == -EINVAL && force) { @@ -1668,7 +1668,7 @@ static int security_compute_sid(struct selinux_state *state, } policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { @@ -1880,19 +1880,6 @@ int security_change_sid(struct selinux_state *state, out_sid, false); } -/* Clone the SID into the new SID table. */ -static int clone_sid(u32 sid, - struct context *context, - void *arg) -{ - struct sidtab *s = arg; - - if (sid > SECINITSID_NUM) - return sidtab_insert(s, sid, context); - else - return 0; -} - static inline int convert_context_handle_invalid_context( struct selinux_state *state, struct context *context) @@ -1920,101 +1907,84 @@ struct convert_context_args { /* * Convert the values in the security context - * structure `c' from the values specified + * structure `oldc' from the values specified * in the policy `p->oldp' to the values specified - * in the policy `p->newp'. Verify that the - * context is valid under the new policy. + * in the policy `p->newp', storing the new context + * in `newc'. Verify that the context is valid + * under the new policy. */ -static int convert_context(u32 key, - struct context *c, - void *p) +static int convert_context(struct context *oldc, struct context *newc, void *p) { struct convert_context_args *args; - struct context oldc; struct ocontext *oc; - struct mls_range *range; struct role_datum *role; struct type_datum *typdatum; struct user_datum *usrdatum; char *s; u32 len; - int rc = 0; - - if (key <= SECINITSID_NUM) - goto out; + int rc; args = p; - if (c->str) { - struct context ctx; - - rc = -ENOMEM; - s = kstrdup(c->str, GFP_KERNEL); + if (oldc->str) { + s = kstrdup(oldc->str, GFP_KERNEL); if (!s) - goto out; + return -ENOMEM; rc = string_to_context_struct(args->newp, NULL, s, - &ctx, SECSID_NULL); - kfree(s); - if (!rc) { - pr_info("SELinux: Context %s became valid (mapped).\n", - c->str); - /* Replace string with mapped representation. */ - kfree(c->str); - memcpy(c, &ctx, sizeof(*c)); - goto out; - } else if (rc == -EINVAL) { + newc, SECSID_NULL); + if (rc == -EINVAL) { /* Retain string representation for later mapping. */ - rc = 0; - goto out; - } else { + context_init(newc); + newc->str = s; + newc->len = oldc->len; + return 0; + } + kfree(s); + if (rc) { /* Other error condition, e.g. ENOMEM. */ pr_err("SELinux: Unable to map context %s, rc = %d.\n", - c->str, -rc); - goto out; + oldc->str, -rc); + return rc; } + pr_info("SELinux: Context %s became valid (mapped).\n", + oldc->str); + return 0; } - rc = context_cpy(&oldc, c); - if (rc) - goto out; + context_init(newc); /* Convert the user. */ rc = -EINVAL; usrdatum = hashtab_search(args->newp->p_users.table, - sym_name(args->oldp, SYM_USERS, c->user - 1)); + sym_name(args->oldp, + SYM_USERS, oldc->user - 1)); if (!usrdatum) goto bad; - c->user = usrdatum->value; + newc->user = usrdatum->value; /* Convert the role. */ rc = -EINVAL; role = hashtab_search(args->newp->p_roles.table, - sym_name(args->oldp, SYM_ROLES, c->role - 1)); + sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); if (!role) goto bad; - c->role = role->value; + newc->role = role->value; /* Convert the type. */ rc = -EINVAL; typdatum = hashtab_search(args->newp->p_types.table, - sym_name(args->oldp, SYM_TYPES, c->type - 1)); + sym_name(args->oldp, + SYM_TYPES, oldc->type - 1)); if (!typdatum) goto bad; - c->type = typdatum->value; + newc->type = typdatum->value; /* Convert the MLS fields if dealing with MLS policies */ if (args->oldp->mls_enabled && args->newp->mls_enabled) { - rc = mls_convert_context(args->oldp, args->newp, c); + rc = mls_convert_context(args->oldp, args->newp, oldc, newc); if (rc) goto bad; - } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) { - /* - * Switching between MLS and non-MLS policy: - * free any storage used by the MLS fields in the - * context for all existing entries in the sidtab. - */ - mls_context_destroy(c); } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { /* * Switching between non-MLS and MLS policy: @@ -2032,38 +2002,30 @@ static int convert_context(u32 key, " the initial SIDs list\n"); goto bad; } - range = &oc->context[0].range; - rc = mls_range_set(c, range); + rc = mls_range_set(newc, &oc->context[0].range); if (rc) goto bad; } /* Check the validity of the new context. */ - if (!policydb_context_isvalid(args->newp, c)) { - rc = convert_context_handle_invalid_context(args->state, - &oldc); + if (!policydb_context_isvalid(args->newp, newc)) { + rc = convert_context_handle_invalid_context(args->state, oldc); if (rc) goto bad; } - context_destroy(&oldc); - - rc = 0; -out: - return rc; + return 0; bad: /* Map old representation to string and save it. */ - rc = context_struct_to_string(args->oldp, &oldc, &s, &len); + rc = context_struct_to_string(args->oldp, oldc, &s, &len); if (rc) return rc; - context_destroy(&oldc); - context_destroy(c); - c->str = s; - c->len = len; + context_destroy(newc); + newc->str = s; + newc->len = len; pr_info("SELinux: Context %s became invalid (unmapped).\n", - c->str); - rc = 0; - goto out; + newc->str); + return 0; } static void security_load_policycaps(struct selinux_state *state) @@ -2103,11 +2065,11 @@ static int security_preserve_bools(struct selinux_state *state, int security_load_policy(struct selinux_state *state, void *data, size_t len) { struct policydb *policydb; - struct sidtab *sidtab; + struct sidtab *oldsidtab, *newsidtab; struct policydb *oldpolicydb, *newpolicydb; - struct sidtab oldsidtab, newsidtab; struct selinux_mapping *oldmapping; struct selinux_map newmap; + struct sidtab_convert_params convert_params; struct convert_context_args args; u32 seqno; int rc = 0; @@ -2121,27 +2083,37 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) newpolicydb = oldpolicydb + 1; policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + + newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL); + if (!newsidtab) { + rc = -ENOMEM; + goto out; + } if (!state->initialized) { rc = policydb_read(policydb, fp); - if (rc) + if (rc) { + kfree(newsidtab); goto out; + } policydb->len = len; rc = selinux_set_mapping(policydb, secclass_map, &state->ss->map); if (rc) { + kfree(newsidtab); policydb_destroy(policydb); goto out; } - rc = policydb_load_isids(policydb, sidtab); + rc = policydb_load_isids(policydb, newsidtab); if (rc) { + kfree(newsidtab); policydb_destroy(policydb); goto out; } + state->ss->sidtab = newsidtab; security_load_policycaps(state); state->initialized = 1; seqno = ++state->ss->latest_granting; @@ -2154,13 +2126,11 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) goto out; } -#if 0 - sidtab_hash_eval(sidtab, "sids"); -#endif - rc = policydb_read(newpolicydb, fp); - if (rc) + if (rc) { + kfree(newsidtab); goto out; + } newpolicydb->len = len; /* If switching between different policy types, log MLS status */ @@ -2169,10 +2139,11 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) else if (!policydb->mls_enabled && newpolicydb->mls_enabled) pr_info("SELinux: Enabling MLS support...\n"); - rc = policydb_load_isids(newpolicydb, &newsidtab); + rc = policydb_load_isids(newpolicydb, newsidtab); if (rc) { pr_err("SELinux: unable to load the initial SIDs\n"); policydb_destroy(newpolicydb); + kfree(newsidtab); goto out; } @@ -2186,12 +2157,7 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) goto err; } - /* Clone the SID table. */ - sidtab_shutdown(sidtab); - - rc = sidtab_map(sidtab, clone_sid, &newsidtab); - if (rc) - goto err; + oldsidtab = state->ss->sidtab; /* * Convert the internal representations of contexts @@ -2200,7 +2166,12 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) args.state = state; args.oldp = policydb; args.newp = newpolicydb; - rc = sidtab_map(&newsidtab, convert_context, &args); + + convert_params.func = convert_context; + convert_params.args = &args; + convert_params.target = newsidtab; + + rc = sidtab_convert(oldsidtab, &convert_params); if (rc) { pr_err("SELinux: unable to convert the internal" " representation of contexts in the new SID" @@ -2210,12 +2181,11 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) /* Save the old policydb and SID table to free later. */ memcpy(oldpolicydb, policydb, sizeof(*policydb)); - sidtab_set(&oldsidtab, sidtab); /* Install the new policydb and SID table. */ write_lock_irq(&state->ss->policy_rwlock); memcpy(policydb, newpolicydb, sizeof(*policydb)); - sidtab_set(sidtab, &newsidtab); + state->ss->sidtab = newsidtab; security_load_policycaps(state); oldmapping = state->ss->map.mapping; state->ss->map.mapping = newmap.mapping; @@ -2225,7 +2195,8 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) /* Free the old policydb and SID table. */ policydb_destroy(oldpolicydb); - sidtab_destroy(&oldsidtab); + sidtab_destroy(oldsidtab); + kfree(oldsidtab); kfree(oldmapping); avc_ss_reset(state->avc, seqno); @@ -2239,7 +2210,8 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len) err: kfree(newmap.mapping); - sidtab_destroy(&newsidtab); + sidtab_destroy(newsidtab); + kfree(newsidtab); policydb_destroy(newpolicydb); out: @@ -2276,7 +2248,7 @@ int security_port_sid(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; c = policydb->ocontexts[OCON_PORT]; while (c) { @@ -2322,7 +2294,7 @@ int security_ib_pkey_sid(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; c = policydb->ocontexts[OCON_IBPKEY]; while (c) { @@ -2368,7 +2340,7 @@ int security_ib_endport_sid(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; c = policydb->ocontexts[OCON_IBENDPORT]; while (c) { @@ -2414,7 +2386,7 @@ int security_netif_sid(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; c = policydb->ocontexts[OCON_NETIF]; while (c) { @@ -2479,7 +2451,7 @@ int security_node_sid(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; switch (domain) { case AF_INET: { @@ -2579,7 +2551,7 @@ int security_get_user_sids(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; context_init(&usercon); @@ -2681,7 +2653,7 @@ static inline int __security_genfs_sid(struct selinux_state *state, u32 *sid) { struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = &state->ss->sidtab; + struct sidtab *sidtab = state->ss->sidtab; int len; u16 sclass; struct genfs *genfs; @@ -2767,7 +2739,7 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb) read_lock(&state->ss->policy_rwlock); policydb = &state->ss->policydb; - sidtab = &state->ss->sidtab; + sidtab = state->ss->sidtab; c = policydb->ocontexts[OCON_FSUSE]; while (c) { @@ -2973,7 +2945,7 @@ int security_sid_mls_copy(struct selinux_state *state, u32 sid, u32 mls_sid, u32 *new_sid) { struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = &state->ss->sidtab; + struct sidtab *sidtab = state->ss->sidtab; struct context *context1; struct context *context2; struct context newcon; @@ -3064,7 +3036,7 @@ int security_net_peersid_resolve(struct selinux_state *state, u32 *peer_sid) { struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = &state->ss->sidtab; + struct sidtab *sidtab = state->ss->sidtab; int rc; struct context *nlbl_ctx; struct context *xfrm_ctx; @@ -3425,7 +3397,7 @@ int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, goto out; } - ctxt = sidtab_search(&state->ss->sidtab, sid); + ctxt = sidtab_search(state->ss->sidtab, sid); if (unlikely(!ctxt)) { WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", sid); @@ -3588,7 +3560,7 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state, u32 *sid) { struct policydb *policydb = &state->ss->policydb; - struct sidtab *sidtab = &state->ss->sidtab; + struct sidtab *sidtab = state->ss->sidtab; int rc; struct context *ctx; struct context ctx_new; @@ -3666,7 +3638,7 @@ int security_netlbl_sid_to_secattr(struct selinux_state *state, read_lock(&state->ss->policy_rwlock); rc = -ENOENT; - ctx = sidtab_search(&state->ss->sidtab, sid); + ctx = sidtab_search(state->ss->sidtab, sid); if (ctx == NULL) goto out; diff --git a/security/selinux/ss/services.h b/security/selinux/ss/services.h index 24c7bdcc8075..9a36de860368 100644 --- a/security/selinux/ss/services.h +++ b/security/selinux/ss/services.h @@ -24,7 +24,7 @@ struct selinux_map { }; struct selinux_ss { - struct sidtab sidtab; + struct sidtab *sidtab; struct policydb policydb; rwlock_t policy_rwlock; u32 latest_granting; diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index fd75a12fa8fc..e63a90ff2728 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -2,108 +2,164 @@ /* * Implementation of the SID table type. * - * Author : Stephen Smalley, <sds@tycho.nsa.gov> + * Original author: Stephen Smalley, <sds@tycho.nsa.gov> + * Author: Ondrej Mosnacek, <omosnacek@gmail.com> + * + * Copyright (C) 2018 Red Hat, Inc. */ +#include <linux/errno.h> #include <linux/kernel.h> #include <linux/slab.h> +#include <linux/sched.h> #include <linux/spinlock.h> -#include <linux/errno.h> +#include <linux/atomic.h> #include "flask.h" #include "security.h" #include "sidtab.h" -#define SIDTAB_HASH(sid) \ -(sid & SIDTAB_HASH_MASK) - int sidtab_init(struct sidtab *s) { - int i; - - s->htable = kmalloc_array(SIDTAB_SIZE, sizeof(*s->htable), GFP_ATOMIC); - if (!s->htable) - return -ENOMEM; - for (i = 0; i < SIDTAB_SIZE; i++) - s->htable[i] = NULL; - s->nel = 0; - s->next_sid = 1; - s->shutdown = 0; + u32 i; + + memset(s->roots, 0, sizeof(s->roots)); + + for (i = 0; i < SIDTAB_RCACHE_SIZE; i++) + atomic_set(&s->rcache[i], -1); + + for (i = 0; i < SECINITSID_NUM; i++) + s->isids[i].set = 0; + + atomic_set(&s->count, 0); + + s->convert = NULL; + spin_lock_init(&s->lock); return 0; } -int sidtab_insert(struct sidtab *s, u32 sid, struct context *context) +int sidtab_set_initial(struct sidtab *s, u32 sid, struct context *context) { - int hvalue; - struct sidtab_node *prev, *cur, *newnode; - - if (!s) - return -ENOMEM; - - hvalue = SIDTAB_HASH(sid); - prev = NULL; - cur = s->htable[hvalue]; - while (cur && sid > cur->sid) { - prev = cur; - cur = cur->next; - } + struct sidtab_isid_entry *entry; + int rc; - if (cur && sid == cur->sid) - return -EEXIST; + if (sid == 0 || sid > SECINITSID_NUM) + return -EINVAL; - newnode = kmalloc(sizeof(*newnode), GFP_ATOMIC); - if (!newnode) - return -ENOMEM; + entry = &s->isids[sid - 1]; - newnode->sid = sid; - if (context_cpy(&newnode->context, context)) { - kfree(newnode); - return -ENOMEM; - } + rc = context_cpy(&entry->context, context); + if (rc) + return rc; - if (prev) { - newnode->next = prev->next; - wmb(); - prev->next = newnode; - } else { - newnode->next = s->htable[hvalue]; - wmb(); - s->htable[hvalue] = newnode; + entry->set = 1; + return 0; +} + +static u32 sidtab_level_from_count(u32 count) +{ + u32 capacity = SIDTAB_LEAF_ENTRIES; + u32 level = 0; + + while (count > capacity) { + capacity <<= SIDTAB_INNER_SHIFT; + ++level; } + return level; +} - s->nel++; - if (sid >= s->next_sid) - s->next_sid = sid + 1; +static int sidtab_alloc_roots(struct sidtab *s, u32 level) +{ + u32 l; + + if (!s->roots[0].ptr_leaf) { + s->roots[0].ptr_leaf = kzalloc(SIDTAB_NODE_ALLOC_SIZE, + GFP_ATOMIC); + if (!s->roots[0].ptr_leaf) + return -ENOMEM; + } + for (l = 1; l <= level; ++l) + if (!s->roots[l].ptr_inner) { + s->roots[l].ptr_inner = kzalloc(SIDTAB_NODE_ALLOC_SIZE, + GFP_ATOMIC); + if (!s->roots[l].ptr_inner) + return -ENOMEM; + s->roots[l].ptr_inner->entries[0] = s->roots[l - 1]; + } return 0; } -static struct context *sidtab_search_core(struct sidtab *s, u32 sid, int force) +static struct context *sidtab_do_lookup(struct sidtab *s, u32 index, int alloc) { - int hvalue; - struct sidtab_node *cur; + union sidtab_entry_inner *entry; + u32 level, capacity_shift, leaf_index = index / SIDTAB_LEAF_ENTRIES; + + /* find the level of the subtree we need */ + level = sidtab_level_from_count(index + 1); + capacity_shift = level * SIDTAB_INNER_SHIFT; - if (!s) + /* allocate roots if needed */ + if (alloc && sidtab_alloc_roots(s, level) != 0) return NULL; - hvalue = SIDTAB_HASH(sid); - cur = s->htable[hvalue]; - while (cur && sid > cur->sid) - cur = cur->next; - - if (force && cur && sid == cur->sid && cur->context.len) - return &cur->context; - - if (!cur || sid != cur->sid || cur->context.len) { - /* Remap invalid SIDs to the unlabeled SID. */ - sid = SECINITSID_UNLABELED; - hvalue = SIDTAB_HASH(sid); - cur = s->htable[hvalue]; - while (cur && sid > cur->sid) - cur = cur->next; - if (!cur || sid != cur->sid) + /* lookup inside the subtree */ + entry = &s->roots[level]; + while (level != 0) { + capacity_shift -= SIDTAB_INNER_SHIFT; + --level; + + entry = &entry->ptr_inner->entries[leaf_index >> capacity_shift]; + leaf_index &= ((u32)1 << capacity_shift) - 1; + + if (!entry->ptr_inner) { + if (alloc) + entry->ptr_inner = kzalloc(SIDTAB_NODE_ALLOC_SIZE, + GFP_ATOMIC); + if (!entry->ptr_inner) + return NULL; + } + } + if (!entry->ptr_leaf) { + if (alloc) + entry->ptr_leaf = kzalloc(SIDTAB_NODE_ALLOC_SIZE, + GFP_ATOMIC); + if (!entry->ptr_leaf) return NULL; } + return &entry->ptr_leaf->entries[index % SIDTAB_LEAF_ENTRIES].context; +} + +static struct context *sidtab_lookup(struct sidtab *s, u32 index) +{ + u32 count = (u32)atomic_read(&s->count); + + if (index >= count) + return NULL; + + /* read entries after reading count */ + smp_rmb(); + + return sidtab_do_lookup(s, index, 0); +} + +static struct context *sidtab_lookup_initial(struct sidtab *s, u32 sid) +{ + return s->isids[sid - 1].set ? &s->isids[sid - 1].context : NULL; +} + +static struct context *sidtab_search_core(struct sidtab *s, u32 sid, int force) +{ + struct context *context; + + if (sid != 0) { + if (sid > |