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-rw-r--r--security/selinux/hooks.c175
1 files changed, 94 insertions, 81 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 75c2e99bfb81..4bf4807f2d44 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -443,8 +443,7 @@ out:
443 * mount options, or whatever. 443 * mount options, or whatever.
444 */ 444 */
445static int selinux_get_mnt_opts(const struct super_block *sb, 445static int selinux_get_mnt_opts(const struct super_block *sb,
446 char ***mount_options, int **mnt_opts_flags, 446 struct security_mnt_opts *opts)
447 int *num_opts)
448{ 447{
449 int rc = 0, i; 448 int rc = 0, i;
450 struct superblock_security_struct *sbsec = sb->s_security; 449 struct superblock_security_struct *sbsec = sb->s_security;
@@ -452,9 +451,7 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
452 u32 len; 451 u32 len;
453 char tmp; 452 char tmp;
454 453
455 *num_opts = 0; 454 security_init_mnt_opts(opts);
456 *mount_options = NULL;
457 *mnt_opts_flags = NULL;
458 455
459 if (!sbsec->initialized) 456 if (!sbsec->initialized)
460 return -EINVAL; 457 return -EINVAL;
@@ -470,18 +467,18 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
470 /* count the number of mount options for this sb */ 467 /* count the number of mount options for this sb */
471 for (i = 0; i < 8; i++) { 468 for (i = 0; i < 8; i++) {
472 if (tmp & 0x01) 469 if (tmp & 0x01)
473 (*num_opts)++; 470 opts->num_mnt_opts++;
474 tmp >>= 1; 471 tmp >>= 1;
475 } 472 }
476 473
477 *mount_options = kcalloc(*num_opts, sizeof(char *), GFP_ATOMIC); 474 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
478 if (!*mount_options) { 475 if (!opts->mnt_opts) {
479 rc = -ENOMEM; 476 rc = -ENOMEM;
480 goto out_free; 477 goto out_free;
481 } 478 }
482 479
483 *mnt_opts_flags = kcalloc(*num_opts, sizeof(int), GFP_ATOMIC); 480 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
484 if (!*mnt_opts_flags) { 481 if (!opts->mnt_opts_flags) {
485 rc = -ENOMEM; 482 rc = -ENOMEM;
486 goto out_free; 483 goto out_free;
487 } 484 }
@@ -491,22 +488,22 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
491 rc = security_sid_to_context(sbsec->sid, &context, &len); 488 rc = security_sid_to_context(sbsec->sid, &context, &len);
492 if (rc) 489 if (rc)
493 goto out_free; 490 goto out_free;
494 (*mount_options)[i] = context; 491 opts->mnt_opts[i] = context;
495 (*mnt_opts_flags)[i++] = FSCONTEXT_MNT; 492 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
496 } 493 }
497 if (sbsec->flags & CONTEXT_MNT) { 494 if (sbsec->flags & CONTEXT_MNT) {
498 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 495 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
499 if (rc) 496 if (rc)
500 goto out_free; 497 goto out_free;
501 (*mount_options)[i] = context; 498 opts->mnt_opts[i] = context;
502 (*mnt_opts_flags)[i++] = CONTEXT_MNT; 499 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
503 } 500 }
504 if (sbsec->flags & DEFCONTEXT_MNT) { 501 if (sbsec->flags & DEFCONTEXT_MNT) {
505 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 502 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
506 if (rc) 503 if (rc)
507 goto out_free; 504 goto out_free;
508 (*mount_options)[i] = context; 505 opts->mnt_opts[i] = context;
509 (*mnt_opts_flags)[i++] = DEFCONTEXT_MNT; 506 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
510 } 507 }
511 if (sbsec->flags & ROOTCONTEXT_MNT) { 508 if (sbsec->flags & ROOTCONTEXT_MNT) {
512 struct inode *root = sbsec->sb->s_root->d_inode; 509 struct inode *root = sbsec->sb->s_root->d_inode;
@@ -515,24 +512,16 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
515 rc = security_sid_to_context(isec->sid, &context, &len); 512 rc = security_sid_to_context(isec->sid, &context, &len);
516 if (rc) 513 if (rc)
517 goto out_free; 514 goto out_free;
518 (*mount_options)[i] = context; 515 opts->mnt_opts[i] = context;
519 (*mnt_opts_flags)[i++] = ROOTCONTEXT_MNT; 516 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
520 } 517 }
521 518
522 BUG_ON(i != *num_opts); 519 BUG_ON(i != opts->num_mnt_opts);
523 520
524 return 0; 521 return 0;
525 522
526out_free: 523out_free:
527 /* don't leak context string if security_sid_to_context had an error */ 524 security_free_mnt_opts(opts);
528 if (*mount_options && i)
529 for (; i > 0; i--)
530 kfree((*mount_options)[i-1]);
531 kfree(*mount_options);
532 *mount_options = NULL;
533 kfree(*mnt_opts_flags);
534 *mnt_opts_flags = NULL;
535 *num_opts = 0;
536 return rc; 525 return rc;
537} 526}
538 527
@@ -553,12 +542,13 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag,
553 return 1; 542 return 1;
554 return 0; 543 return 0;
555} 544}
545
556/* 546/*
557 * Allow filesystems with binary mount data to explicitly set mount point 547 * Allow filesystems with binary mount data to explicitly set mount point
558 * labeling information. 548 * labeling information.
559 */ 549 */
560static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options, 550static int selinux_set_mnt_opts(struct super_block *sb,
561 int *flags, int num_opts) 551 struct security_mnt_opts *opts)
562{ 552{
563 int rc = 0, i; 553 int rc = 0, i;
564 struct task_security_struct *tsec = current->security; 554 struct task_security_struct *tsec = current->security;
@@ -568,6 +558,9 @@ static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options,
568 struct inode_security_struct *root_isec = inode->i_security; 558 struct inode_security_struct *root_isec = inode->i_security;
569 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 559 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
570 u32 defcontext_sid = 0; 560 u32 defcontext_sid = 0;
561 char **mount_options = opts->mnt_opts;
562 int *flags = opts->mnt_opts_flags;
563 int num_opts = opts->num_mnt_opts;
571 564
572 mutex_lock(&sbsec->lock); 565 mutex_lock(&sbsec->lock);
573 566
@@ -589,6 +582,21 @@ static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options,
589 } 582 }
590 583
591 /* 584 /*
585 * Binary mount data FS will come through this function twice. Once
586 * from an explicit call and once from the generic calls from the vfs.
587 * Since the generic VFS calls will not contain any security mount data
588 * we need to skip the double mount verification.
589 *
590 * This does open a hole in which we will not notice if the first
591 * mount using this sb set explict options and a second mount using
592 * this sb does not set any security options. (The first options
593 * will be used for both mounts)
594 */
595 if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
596 && (num_opts == 0))
597 goto out;
598
599 /*
592 * parse the mount options, check if they are valid sids. 600 * parse the mount options, check if they are valid sids.
593 * also check if someone is trying to mount the same sb more 601 * also check if someone is trying to mount the same sb more
594 * than once with different security options. 602 * than once with different security options.
@@ -792,43 +800,14 @@ static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
792 mutex_unlock(&newsbsec->lock); 800 mutex_unlock(&newsbsec->lock);
793} 801}
794 802
795/* 803int selinux_parse_opts_str(char *options, struct security_mnt_opts *opts)
796 * string mount options parsing and call set the sbsec
797 */
798static int superblock_doinit(struct super_block *sb, void *data)
799{ 804{
805 char *p;
800 char *context = NULL, *defcontext = NULL; 806 char *context = NULL, *defcontext = NULL;
801 char *fscontext = NULL, *rootcontext = NULL; 807 char *fscontext = NULL, *rootcontext = NULL;
802 int rc = 0; 808 int rc, num_mnt_opts = 0;
803 char *p, *options = data;
804 /* selinux only know about a fixed number of mount options */
805 char *mnt_opts[NUM_SEL_MNT_OPTS];
806 int mnt_opts_flags[NUM_SEL_MNT_OPTS], num_mnt_opts = 0;
807
808 if (!data)
809 goto out;
810 809
811 /* with the nfs patch this will become a goto out; */ 810 opts->num_mnt_opts = 0;
812 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
813 const char *name = sb->s_type->name;
814 /* NFS we understand. */
815 if (!strcmp(name, "nfs")) {
816 struct nfs_mount_data *d = data;
817
818 if (d->version != NFS_MOUNT_VERSION)
819 goto out;
820
821 if (d->context[0]) {
822 context = kstrdup(d->context, GFP_KERNEL);
823 if (!context) {
824 rc = -ENOMEM;
825 goto out;
826 }
827 }
828 goto build_flags;
829 } else
830 goto out;
831 }
832 811
833 /* Standard string-based options. */ 812 /* Standard string-based options. */
834 while ((p = strsep(&options, "|")) != NULL) { 813 while ((p = strsep(&options, "|")) != NULL) {
@@ -901,26 +880,37 @@ static int superblock_doinit(struct super_block *sb, void *data)
901 } 880 }
902 } 881 }
903 882
904build_flags: 883 rc = -ENOMEM;
884 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
885 if (!opts->mnt_opts)
886 goto out_err;
887
888 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
889 if (!opts->mnt_opts_flags) {
890 kfree(opts->mnt_opts);
891 goto out_err;
892 }
893
905 if (fscontext) { 894 if (fscontext) {
906 mnt_opts[num_mnt_opts] = fscontext; 895 opts->mnt_opts[num_mnt_opts] = fscontext;
907 mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 896 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 } 897 }
909 if (context) { 898 if (context) {
910 mnt_opts[num_mnt_opts] = context; 899 opts->mnt_opts[num_mnt_opts] = context;
911 mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 900 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 } 901 }
913 if (rootcontext) { 902 if (rootcontext) {
914 mnt_opts[num_mnt_opts] = rootcontext; 903 opts->mnt_opts[num_mnt_opts] = rootcontext;
915 mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 904 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 } 905 }
917 if (defcontext) { 906 if (defcontext) {
918 mnt_opts[num_mnt_opts] = defcontext; 907 opts->mnt_opts[num_mnt_opts] = defcontext;
919 mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 908 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 } 909 }
921 910
922out: 911 opts->num_mnt_opts = num_mnt_opts;
923 rc = selinux_set_mnt_opts(sb, mnt_opts, mnt_opts_flags, num_mnt_opts); 912 return 0;
913
924out_err: 914out_err:
925 kfree(context); 915 kfree(context);
926 kfree(defcontext); 916 kfree(defcontext);
@@ -928,6 +918,33 @@ out_err:
928 kfree(rootcontext); 918 kfree(rootcontext);
929 return rc; 919 return rc;
930} 920}
921/*
922 * string mount options parsing and call set the sbsec
923 */
924static int superblock_doinit(struct super_block *sb, void *data)
925{
926 int rc = 0;
927 char *options = data;
928 struct security_mnt_opts opts;
929
930 security_init_mnt_opts(&opts);
931
932 if (!data)
933 goto out;
934
935 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
936
937 rc = selinux_parse_opts_str(options, &opts);
938 if (rc)
939 goto out_err;
940
941out:
942 rc = selinux_set_mnt_opts(sb, &opts);
943
944out_err:
945 security_free_mnt_opts(&opts);
946 return rc;
947}
931 948
932static inline u16 inode_mode_to_security_class(umode_t mode) 949static inline u16 inode_mode_to_security_class(umode_t mode)
933{ 950{
@@ -2253,7 +2270,7 @@ static inline void take_selinux_option(char **to, char *from, int *first,
2253 } 2270 }
2254} 2271}
2255 2272
2256static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) 2273static int selinux_sb_copy_data(char *orig, char *copy)
2257{ 2274{
2258 int fnosec, fsec, rc = 0; 2275 int fnosec, fsec, rc = 0;
2259 char *in_save, *in_curr, *in_end; 2276 char *in_save, *in_curr, *in_end;
@@ -2263,12 +2280,6 @@ static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void
2263 in_curr = orig; 2280 in_curr = orig;
2264 sec_curr = copy; 2281 sec_curr = copy;
2265 2282
2266 /* Binary mount data: just copy */
2267 if (type->fs_flags & FS_BINARY_MOUNTDATA) {
2268 copy_page(sec_curr, in_curr);
2269 goto out;
2270 }
2271
2272 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2283 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2273 if (!nosec) { 2284 if (!nosec) {
2274 rc = -ENOMEM; 2285 rc = -ENOMEM;
@@ -5251,6 +5262,8 @@ static struct security_operations selinux_ops = {
5251 .sb_get_mnt_opts = selinux_get_mnt_opts, 5262 .sb_get_mnt_opts = selinux_get_mnt_opts,
5252 .sb_set_mnt_opts = selinux_set_mnt_opts, 5263 .sb_set_mnt_opts = selinux_set_mnt_opts,
5253 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5264 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5265 .sb_parse_opts_str = selinux_parse_opts_str,
5266
5254 5267
5255 .inode_alloc_security = selinux_inode_alloc_security, 5268 .inode_alloc_security = selinux_inode_alloc_security,
5256 .inode_free_security = selinux_inode_free_security, 5269 .inode_free_security = selinux_inode_free_security,