From 6f5d51148921c242680a7a1d9913384a30ab3cbe Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 19 Dec 2009 15:59:45 +0000 Subject: fix braindamage in audit_tree.c untag_chunk() ... aka "Al had badly fscked up when writing that thing and nobody noticed until Eric had fixed leaks that used to mask the breakage". The function essentially creates a copy of old array sans one element and replaces the references to elements of original (they are on cyclic lists) with those to corresponding elements of new one. After that the old one is fair game for freeing. First of all, there's a dumb braino: when we get to list_replace_init we use indices for wrong arrays - position in new one with the old array and vice versa. Another bug is more subtle - termination condition is wrong if the element to be excluded happens to be the last one. We shouldn't go until we fill the new array, we should go until we'd finished the old one. Otherwise the element we are trying to kill will remain on the cyclic lists... That crap used to be masked by several leaks, so it was not quite trivial to hit. Eric had fixed some of those leaks a while ago and the shit had hit the fan... Signed-off-by: Al Viro Signed-off-by: Linus Torvalds --- kernel/audit_tree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/audit_tree.c') diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 2451dc6f3282..b36aa9651ba2 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -277,7 +277,7 @@ static void untag_chunk(struct node *p) owner->root = NULL; } - for (i = j = 0; i < size; i++, j++) { + for (i = j = 0; j <= size; i++, j++) { struct audit_tree *s; if (&chunk->owners[j] == p) { list_del_init(&p->list); @@ -290,7 +290,7 @@ static void untag_chunk(struct node *p) if (!s) /* result of earlier fallback */ continue; get_tree(s); - list_replace_init(&chunk->owners[i].list, &new->owners[j].list); + list_replace_init(&chunk->owners[j].list, &new->owners[i].list); } list_replace_rcu(&chunk->hash, &new->hash); -- cgit v1.2.2 From b4c30aad39805902cf5b855aa8a8b22d728ad057 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 19 Dec 2009 16:03:30 +0000 Subject: fix more leaks in audit_tree.c tag_chunk() Several leaks in audit_tree didn't get caught by commit 318b6d3d7ddbcad3d6867e630711b8a705d873d7, including the leak on normal exit in case of multiple rules refering to the same chunk. Signed-off-by: Al Viro Signed-off-by: Linus Torvalds --- kernel/audit_tree.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'kernel/audit_tree.c') diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index b36aa9651ba2..4b05bd9479db 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -373,15 +373,17 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) for (n = 0; n < old->count; n++) { if (old->owners[n].owner == tree) { spin_unlock(&hash_lock); - put_inotify_watch(watch); + put_inotify_watch(&old->watch); return 0; } } spin_unlock(&hash_lock); chunk = alloc_chunk(old->count + 1); - if (!chunk) + if (!chunk) { + put_inotify_watch(&old->watch); return -ENOMEM; + } mutex_lock(&inode->inotify_mutex); if (inotify_clone_watch(&old->watch, &chunk->watch) < 0) { @@ -425,7 +427,8 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) spin_unlock(&hash_lock); inotify_evict_watch(&old->watch); mutex_unlock(&inode->inotify_mutex); - put_inotify_watch(&old->watch); + put_inotify_watch(&old->watch); /* pair to inotify_find_watch */ + put_inotify_watch(&old->watch); /* and kill it */ return 0; } -- cgit v1.2.2 From 2096f759abcb42200a81d776f597362fd9265024 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 30 Jan 2010 13:16:21 -0500 Subject: New helper: path_is_under(path1, path2) Analog of is_subdir for vfsmount,dentry pairs, moved from audit_tree.c Signed-off-by: Al Viro --- kernel/audit_tree.c | 51 ++++++++++++--------------------------------------- 1 file changed, 12 insertions(+), 39 deletions(-) (limited to 'kernel/audit_tree.c') diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 4b05bd9479db..f09b42d9c32d 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -603,22 +603,6 @@ skip_it: mutex_unlock(&audit_filter_mutex); } -static int is_under(struct vfsmount *mnt, struct dentry *dentry, - struct path *path) -{ - if (mnt != path->mnt) { - for (;;) { - if (mnt->mnt_parent == mnt) - return 0; - if (mnt->mnt_parent == path->mnt) - break; - mnt = mnt->mnt_parent; - } - dentry = mnt->mnt_mountpoint; - } - return is_subdir(dentry, path->dentry); -} - int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op) { @@ -714,29 +698,24 @@ int audit_tag_tree(char *old, char *new) { struct list_head cursor, barrier; int failed = 0; - struct path path; + struct path path1, path2; struct vfsmount *tagged; struct list_head list; - struct vfsmount *mnt; - struct dentry *dentry; int err; - err = kern_path(new, 0, &path); + err = kern_path(new, 0, &path2); if (err) return err; - tagged = collect_mounts(&path); - path_put(&path); + tagged = collect_mounts(&path2); + path_put(&path2); if (!tagged) return -ENOMEM; - err = kern_path(old, 0, &path); + err = kern_path(old, 0, &path1); if (err) { drop_collected_mounts(tagged); return err; } - mnt = mntget(path.mnt); - dentry = dget(path.dentry); - path_put(&path); list_add_tail(&list, &tagged->mnt_list); @@ -747,6 +726,7 @@ int audit_tag_tree(char *old, char *new) while (cursor.next != &tree_list) { struct audit_tree *tree; struct vfsmount *p; + int good_one = 0; tree = container_of(cursor.next, struct audit_tree, list); get_tree(tree); @@ -754,23 +734,17 @@ int audit_tag_tree(char *old, char *new) list_add(&cursor, &tree->list); mutex_unlock(&audit_filter_mutex); - err = kern_path(tree->pathname, 0, &path); - if (err) { - put_tree(tree); - mutex_lock(&audit_filter_mutex); - continue; + err = kern_path(tree->pathname, 0, &path2); + if (!err) { + good_one = path_is_under(&path1, &path2); + path_put(&path2); } - spin_lock(&vfsmount_lock); - if (!is_under(mnt, dentry, &path)) { - spin_unlock(&vfsmount_lock); - path_put(&path); + if (!good_one) { put_tree(tree); mutex_lock(&audit_filter_mutex); continue; } - spin_unlock(&vfsmount_lock); - path_put(&path); list_for_each_entry(p, &list, mnt_list) { failed = tag_chunk(p->mnt_root->d_inode, tree); @@ -820,8 +794,7 @@ int audit_tag_tree(char *old, char *new) list_del(&cursor); list_del(&list); mutex_unlock(&audit_filter_mutex); - dput(dentry); - mntput(mnt); + path_put(&path1); drop_collected_mounts(tagged); return failed; } -- cgit v1.2.2 From 1f707137b55764740981d022d29c622832a61880 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 30 Jan 2010 22:51:25 -0500 Subject: new helper: iterate_mounts() apply function to vfsmounts in set returned by collect_mounts(), stop if it returns non-zero. Signed-off-by: Al Viro --- kernel/audit_tree.c | 49 ++++++++++++++++--------------------------------- 1 file changed, 16 insertions(+), 33 deletions(-) (limited to 'kernel/audit_tree.c') diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index f09b42d9c32d..028e85663f27 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -548,6 +548,11 @@ int audit_remove_tree_rule(struct audit_krule *rule) return 0; } +static int compare_root(struct vfsmount *mnt, void *arg) +{ + return mnt->mnt_root->d_inode == arg; +} + void audit_trim_trees(void) { struct list_head cursor; @@ -559,7 +564,6 @@ void audit_trim_trees(void) struct path path; struct vfsmount *root_mnt; struct node *node; - struct list_head list; int err; tree = container_of(cursor.next, struct audit_tree, list); @@ -577,24 +581,16 @@ void audit_trim_trees(void) if (!root_mnt) goto skip_it; - list_add_tail(&list, &root_mnt->mnt_list); spin_lock(&hash_lock); list_for_each_entry(node, &tree->chunks, list) { - struct audit_chunk *chunk = find_chunk(node); - struct inode *inode = chunk->watch.inode; - struct vfsmount *mnt; + struct inode *inode = find_chunk(node)->watch.inode; node->index |= 1U<<31; - list_for_each_entry(mnt, &list, mnt_list) { - if (mnt->mnt_root->d_inode == inode) { - node->index &= ~(1U<<31); - break; - } - } + if (iterate_mounts(compare_root, inode, root_mnt)) + node->index &= ~(1U<<31); } spin_unlock(&hash_lock); trim_marked(tree); put_tree(tree); - list_del_init(&list); drop_collected_mounts(root_mnt); skip_it: mutex_lock(&audit_filter_mutex); @@ -622,13 +618,17 @@ void audit_put_tree(struct audit_tree *tree) put_tree(tree); } +static int tag_mount(struct vfsmount *mnt, void *arg) +{ + return tag_chunk(mnt->mnt_root->d_inode, arg); +} + /* called with audit_filter_mutex */ int audit_add_tree_rule(struct audit_krule *rule) { struct audit_tree *seed = rule->tree, *tree; struct path path; - struct vfsmount *mnt, *p; - struct list_head list; + struct vfsmount *mnt; int err; list_for_each_entry(tree, &tree_list, list) { @@ -654,16 +654,9 @@ int audit_add_tree_rule(struct audit_krule *rule) err = -ENOMEM; goto Err; } - list_add_tail(&list, &mnt->mnt_list); get_tree(tree); - list_for_each_entry(p, &list, mnt_list) { - err = tag_chunk(p->mnt_root->d_inode, tree); - if (err) - break; - } - - list_del(&list); + err = iterate_mounts(tag_mount, tree, mnt); drop_collected_mounts(mnt); if (!err) { @@ -700,7 +693,6 @@ int audit_tag_tree(char *old, char *new) int failed = 0; struct path path1, path2; struct vfsmount *tagged; - struct list_head list; int err; err = kern_path(new, 0, &path2); @@ -717,15 +709,12 @@ int audit_tag_tree(char *old, char *new) return err; } - list_add_tail(&list, &tagged->mnt_list); - mutex_lock(&audit_filter_mutex); list_add(&barrier, &tree_list); list_add(&cursor, &barrier); while (cursor.next != &tree_list) { struct audit_tree *tree; - struct vfsmount *p; int good_one = 0; tree = container_of(cursor.next, struct audit_tree, list); @@ -746,12 +735,7 @@ int audit_tag_tree(char *old, char *new) continue; } - list_for_each_entry(p, &list, mnt_list) { - failed = tag_chunk(p->mnt_root->d_inode, tree); - if (failed) - break; - } - + failed = iterate_mounts(tag_mount, tree, tagged); if (failed) { put_tree(tree); mutex_lock(&audit_filter_mutex); @@ -792,7 +776,6 @@ int audit_tag_tree(char *old, char *new) } list_del(&barrier); list_del(&cursor); - list_del(&list); mutex_unlock(&audit_filter_mutex); path_put(&path1); drop_collected_mounts(tagged); -- cgit v1.2.2 From 5a0e3ad6af8660be21ca98a971cd00f331318c05 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 24 Mar 2010 17:04:11 +0900 Subject: include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn --- kernel/audit_tree.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/audit_tree.c') diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 028e85663f27..46a57b57a335 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -3,6 +3,7 @@ #include #include #include +#include struct audit_tree; struct audit_chunk; -- cgit v1.2.2