From 782ebb992ec20b5afdd5786ee8c2f1b58b631f24 Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Sat, 3 Sep 2005 15:55:16 -0700 Subject: [PATCH] selinux: Reduce memory use by avtab This patch improves memory use by SELinux by both reducing the avtab node size and reducing the number of avtab nodes. The memory savings are substantial, e.g. on a 64-bit system after boot, James Morris reported the following data for the targeted and strict policies: #objs objsize kernmem Targeted: Before: 237888 40 9.1MB After: 19968 24 468KB Strict: Before: 571680 40 21.81MB After: 221052 24 5.06MB The improvement in memory use comes at a cost in the speed of security server computations of access vectors, but these computations are only required on AVC cache misses, and performance measurements by James Morris using a number of benchmarks have shown that the change does not cause any significant degradation. Note that a rebuilt policy via an updated policy toolchain (libsepol/checkpolicy) is required in order to gain the full benefits of this patch, although some memory savings benefits are immediately applied even to older policies (in particular, the reduction in avtab node size). Sources for the updated toolchain are presently available from the sourceforge CVS tree (http://sourceforge.net/cvs/?group_id=21266), and tarballs are available from http://www.flux.utah.edu/~sds. Signed-off-by: Stephen Smalley Signed-off-by: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/ss/mls.c | 42 +++++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 19 deletions(-) (limited to 'security/selinux/ss/mls.c') diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index d4c32c39ccc9..aaefac2921f1 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -27,6 +27,7 @@ int mls_compute_context_len(struct context * context) { int i, l, len, range; + struct ebitmap_node *node; if (!selinux_mls_enabled) return 0; @@ -36,24 +37,24 @@ int mls_compute_context_len(struct context * context) range = 0; len += strlen(policydb.p_sens_val_to_name[context->range.level[l].sens - 1]); - for (i = 1; i <= ebitmap_length(&context->range.level[l].cat); i++) { - if (ebitmap_get_bit(&context->range.level[l].cat, i - 1)) { + ebitmap_for_each_bit(&context->range.level[l].cat, node, i) { + if (ebitmap_node_get_bit(node, i)) { if (range) { range++; continue; } - len += strlen(policydb.p_cat_val_to_name[i - 1]) + 1; + len += strlen(policydb.p_cat_val_to_name[i]) + 1; range++; } else { if (range > 1) - len += strlen(policydb.p_cat_val_to_name[i - 2]) + 1; + len += strlen(policydb.p_cat_val_to_name[i - 1]) + 1; range = 0; } } /* Handle case where last category is the end of range */ if (range > 1) - len += strlen(policydb.p_cat_val_to_name[i - 2]) + 1; + len += strlen(policydb.p_cat_val_to_name[i - 1]) + 1; if (l == 0) { if (mls_level_eq(&context->range.level[0], @@ -77,6 +78,7 @@ void mls_sid_to_context(struct context *context, { char *scontextp; int i, l, range, wrote_sep; + struct ebitmap_node *node; if (!selinux_mls_enabled) return; @@ -94,8 +96,8 @@ void mls_sid_to_context(struct context *context, scontextp += strlen(policydb.p_sens_val_to_name[context->range.level[l].sens - 1]); /* categories */ - for (i = 1; i <= ebitmap_length(&context->range.level[l].cat); i++) { - if (ebitmap_get_bit(&context->range.level[l].cat, i - 1)) { + ebitmap_for_each_bit(&context->range.level[l].cat, node, i) { + if (ebitmap_node_get_bit(node, i)) { if (range) { range++; continue; @@ -106,8 +108,8 @@ void mls_sid_to_context(struct context *context, wrote_sep = 1; } else *scontextp++ = ','; - strcpy(scontextp, policydb.p_cat_val_to_name[i - 1]); - scontextp += strlen(policydb.p_cat_val_to_name[i - 1]); + strcpy(scontextp, policydb.p_cat_val_to_name[i]); + scontextp += strlen(policydb.p_cat_val_to_name[i]); range++; } else { if (range > 1) { @@ -116,8 +118,8 @@ void mls_sid_to_context(struct context *context, else *scontextp++ = ','; - strcpy(scontextp, policydb.p_cat_val_to_name[i - 2]); - scontextp += strlen(policydb.p_cat_val_to_name[i - 2]); + strcpy(scontextp, policydb.p_cat_val_to_name[i - 1]); + scontextp += strlen(policydb.p_cat_val_to_name[i - 1]); } range = 0; } @@ -130,8 +132,8 @@ void mls_sid_to_context(struct context *context, else *scontextp++ = ','; - strcpy(scontextp, policydb.p_cat_val_to_name[i - 2]); - scontextp += strlen(policydb.p_cat_val_to_name[i - 2]); + strcpy(scontextp, policydb.p_cat_val_to_name[i - 1]); + scontextp += strlen(policydb.p_cat_val_to_name[i - 1]); } if (l == 0) { @@ -157,6 +159,7 @@ int mls_context_isvalid(struct policydb *p, struct context *c) { struct level_datum *levdatum; struct user_datum *usrdatum; + struct ebitmap_node *node; int i, l; if (!selinux_mls_enabled) @@ -179,11 +182,11 @@ int mls_context_isvalid(struct policydb *p, struct context *c) if (!levdatum) return 0; - for (i = 1; i <= ebitmap_length(&c->range.level[l].cat); i++) { - if (ebitmap_get_bit(&c->range.level[l].cat, i - 1)) { + ebitmap_for_each_bit(&c->range.level[l].cat, node, i) { + if (ebitmap_node_get_bit(node, i)) { if (i > p->p_cats.nprim) return 0; - if (!ebitmap_get_bit(&levdatum->level->cat, i - 1)) + if (!ebitmap_get_bit(&levdatum->level->cat, i)) /* * Category may not be associated with * sensitivity in low level. @@ -468,6 +471,7 @@ int mls_convert_context(struct policydb *oldp, struct level_datum *levdatum; struct cat_datum *catdatum; struct ebitmap bitmap; + struct ebitmap_node *node; int l, i; if (!selinux_mls_enabled) @@ -482,12 +486,12 @@ int mls_convert_context(struct policydb *oldp, c->range.level[l].sens = levdatum->level->sens; ebitmap_init(&bitmap); - for (i = 1; i <= ebitmap_length(&c->range.level[l].cat); i++) { - if (ebitmap_get_bit(&c->range.level[l].cat, i - 1)) { + ebitmap_for_each_bit(&c->range.level[l].cat, node, i) { + if (ebitmap_node_get_bit(node, i)) { int rc; catdatum = hashtab_search(newp->p_cats.table, - oldp->p_cat_val_to_name[i - 1]); + oldp->p_cat_val_to_name[i]); if (!catdatum) return -EINVAL; rc = ebitmap_set_bit(&bitmap, catdatum->value - 1, 1); -- cgit v1.2.3-59-g8ed1b