Like commit 42d5e37654e4 ("audit: filter PATH records keyed on filesystem magic") that addresses https://github.com/linux-audit/audit-kernel/issues/8 Any user or remote filesystem could become unavailable and effectively block on a forced unmount. -a always,exit -S umount2 -F key=umount2 Provide a method to ignore these user and remote filesystems to prevent them from being impossible to unmount. Extend the "AUDIT_FILTER_FS" filter that uses the field type AUDIT_FSTYPE keying off the filesystem 4-octet hexadecimal magic identifier to filter specific filesystems to cover audit_inode() to address this blockage. An example rule would look like: -a never,filesystem -F fstype=0x517B -F key=ignore_smb -a never,filesystem -F fstype=0x6969 -F key=ignore_nfs Arguably the better way to address this issue is to disable auditing processes that touch removable filesystems. Note: refactor __audit_inode_child() to remove two levels of if indentation. Please see the github issue tracker https://github.com/linux-audit/audit-kernel/issues/100 Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; --- kernel/auditsc.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/kernel/auditsc.c b/kernel/auditsc.c index b585ceb2f7a2..3d05d5fc6240 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1763,10 +1763,31 @@ void __audit_inode(struct filename *name, const struct dentry *dentry, struct inode *inode = d_backing_inode(dentry); struct audit_names *n; bool parent = flags & AUDIT_INODE_PARENT; + struct audit_entry *e; + struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; + int i; if (!context->in_syscall) return; + rcu_read_lock(); + if (!list_empty(list)) { + list_for_each_entry_rcu(e, list, list) { + for (i = 0; i < e->rule.field_count; i++) { + struct audit_field *f = &e->rule.fields[i]; + + if (f->type == AUDIT_FSTYPE + && audit_comparator(inode->i_sb->s_magic, + f->op, f->val) + && e->rule.action == AUDIT_NEVER) { + rcu_read_unlock(); + return; + } + } + } + } + rcu_read_unlock(); + if (!name) goto out_alloc; @@ -1875,14 +1896,12 @@ void __audit_inode_child(struct inode *parent, for (i = 0; i < e->rule.field_count; i++) { struct audit_field *f = &e->rule.fields[i]; - if (f->type == AUDIT_FSTYPE) { - if (audit_comparator(parent->i_sb->s_magic, - f->op, f->val)) { - if (e->rule.action == AUDIT_NEVER) { - rcu_read_unlock(); - return; - } - } + if (f->type == AUDIT_FSTYPE + && audit_comparator(parent->i_sb->s_magic, + f->op, f->val) + && e->rule.action == AUDIT_NEVER) { + rcu_read_unlock(); + return; } } } -- 1.8.3.1

Don't fetch fcaps when umount2 is called to avoid a process hang while it waits for the missing resource to (possibly never) re-appear. Note the comment above user_path_mountpoint_at(): * A umount is a special case for path walking. We're not actually interested * in the inode in this situation, and ESTALE errors can be a problem. We * simply want track down the dentry and vfsmount attached at the mountpoint * and avoid revalidating the last component. This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. Please see the github issue tracker https://github.com/linux-audit/audit-kernel/issues/100 Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; --- fs/namei.c | 2 +- fs/namespace.c | 2 ++ include/linux/audit.h | 15 ++++++++++----- include/linux/namei.h | 3 +++ kernel/audit.c | 10 +++++++++- kernel/audit.h | 2 +- kernel/auditsc.c | 6 +++--- 7 files changed, 29 insertions(+), 11 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 914178cdbe94..87d7710a2e1d 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2720,7 +2720,7 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags, if (unlikely(error == -ESTALE)) error = path_mountpoint(&nd, flags | LOOKUP_REVAL, path); if (likely(!error)) - audit_inode(name, path->dentry, 0); + audit_inode(name, path->dentry, flags & LOOKUP_NO_EVAL); restore_nameidata(); putname(name); return error; diff --git a/fs/namespace.c b/fs/namespace.c index a677b59efd74..e5de0e372df2 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1640,6 +1640,8 @@ int ksys_umount(char __user *name, int flags) if (!(flags & UMOUNT_NOFOLLOW)) lookup_flags |= LOOKUP_FOLLOW; + lookup_flags |= LOOKUP_NO_EVAL; + retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path); if (retval) goto out; diff --git a/include/linux/audit.h b/include/linux/audit.h index a625c29a2ea2..5d914b534536 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -25,6 +25,7 @@ #include <linux/sched.h> #include <linux/ptrace.h> +#include <linux/namei.h> /* LOOKUP_* */ #include <uapi/linux/audit.h> #define AUDIT_INO_UNSET ((unsigned long)-1) @@ -225,6 +226,7 @@ extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1, #define AUDIT_INODE_PARENT 1 /* dentry represents the parent */ #define AUDIT_INODE_HIDDEN 2 /* audit record should be hidden */ +#define AUDIT_INODE_NOEVAL 4 /* audit record incomplete */ extern void __audit_inode(struct filename *name, const struct dentry *dentry, unsigned int flags); extern void __audit_file(const struct file *); @@ -285,12 +287,15 @@ static inline void audit_getname(struct filename *name) } static inline void audit_inode(struct filename *name, const struct dentry *dentry, - unsigned int parent) { + unsigned int flags) { if (unlikely(!audit_dummy_context())) { - unsigned int flags = 0; - if (parent) - flags |= AUDIT_INODE_PARENT; - __audit_inode(name, dentry, flags); + unsigned int aflags = 0; + + if (flags & LOOKUP_PARENT) + aflags |= AUDIT_INODE_PARENT; + if (flags & LOOKUP_NO_EVAL) + aflags |= AUDIT_INODE_NOEVAL; + __audit_inode(name, dentry, aflags); } } static inline void audit_file(struct file *file) diff --git a/include/linux/namei.h b/include/linux/namei.h index a78606e8e3df..9138b4471dbf 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -24,6 +24,8 @@ * - internal "there are more path components" flag * - dentry cache is untrusted; force a real lookup * - suppress terminal automount + * - skip revalidation + * - don't fetch xattrs on audit_inode */ #define LOOKUP_FOLLOW 0x0001 #define LOOKUP_DIRECTORY 0x0002 @@ -33,6 +35,7 @@ #define LOOKUP_REVAL 0x0020 #define LOOKUP_RCU 0x0040 #define LOOKUP_NO_REVAL 0x0080 +#define LOOKUP_NO_EVAL 0x0100 /* * Intent data diff --git a/kernel/audit.c b/kernel/audit.c index ca55ccb46b76..45d5131943eb 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2081,6 +2081,10 @@ void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) { + if (name->fcap_ver == -1) { + audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); + return; + } audit_log_cap(ab, "cap_fp", &name->fcap.permitted); audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); audit_log_format(ab, " cap_fe=%d cap_fver=%x", @@ -2111,7 +2115,7 @@ static inline int audit_copy_fcaps(struct audit_names *name, /* Copy inode data into an audit_names. */ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, - struct inode *inode) + struct inode *inode, unsigned int flags) { name->ino = inode->i_ino; name->dev = inode->i_sb->s_dev; @@ -2120,6 +2124,10 @@ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, name->gid = inode->i_gid; name->rdev = inode->i_rdev; security_inode_getsecid(inode, &name->osid); + if (flags & AUDIT_INODE_NOEVAL) { + name->fcap_ver = -1; + return; + }

audit_copy_fcaps(name, dentry); } diff --git a/kernel/audit.h b/kernel/audit.h index 6ffb70575082..25ab276be8e5 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -214,7 +214,7 @@ struct audit_context { extern void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, - struct inode *inode); + struct inode *inode, unsigned int flags); extern void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap); extern void audit_log_name(struct audit_context *context, diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 3d05d5fc6240..9a1257afc4d4 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1853,7 +1853,7 @@ void __audit_inode(struct filename *name, const struct dentry *dentry, n->type = AUDIT_TYPE_NORMAL; } handle_path(dentry); - audit_copy_inode(n, dentry, inode); + audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL); } void __audit_file(const struct file *file) @@ -1952,7 +1952,7 @@ void __audit_inode_child(struct inode *parent, n = audit_alloc_name(context, AUDIT_TYPE_PARENT); if (!n) return; - audit_copy_inode(n, NULL, parent); + audit_copy_inode(n, NULL, parent, 0); } if (!found_child) { @@ -1971,7 +1971,7 @@ void __audit_inode_child(struct inode *parent, } if (inode) - audit_copy_inode(found_child, dentry, inode); + audit_copy_inode(found_child, dentry, inode, 0); else found_child->ino = AUDIT_INO_UNSET; } -- 1.8.3.1

On 2019-01-25 16:45, Paul Moore wrote: > On Wed, Jan 23, 2019 at 1:35 PM Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > > Don't fetch fcaps when umount2 is called to avoid a process hang while > > it waits for the missing resource to (possibly never) re-appear. > > > > Note the comment above user_path_mountpoint_at(): > > * A umount is a special case for path walking. We're not actually interested > > * in the inode in this situation, and ESTALE errors can be a problem. We > > * simply want track down the dentry and vfsmount attached at the mountpoint > > * and avoid revalidating the last component. > > > > This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. > > > > Please see the github issue tracker > > https://github.com/linux-audit/audit-kernel/issues/100 > > > > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > > --- > > fs/namei.c | 2 +- > > fs/namespace.c | 2 ++ > > include/linux/audit.h | 15 ++++++++++----- > > include/linux/namei.h | 3 +++ > > kernel/audit.c | 10 +++++++++- > > kernel/audit.h | 2 +- > > kernel/auditsc.c | 6 +++--- > > 7 files changed, 29 insertions(+), 11 deletions(-) > > > > diff --git a/fs/namei.c b/fs/namei.c > > index 914178cdbe94..87d7710a2e1d 100644 > > --- a/fs/namei.c > > +++ b/fs/namei.c > > @@ -2720,7 +2720,7 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags, > > if (unlikely(error == -ESTALE)) > > error = path_mountpoint(&nd, flags | LOOKUP_REVAL, path); > > if (likely(!error)) > > - audit_inode(name, path->dentry, 0); > > + audit_inode(name, path->dentry, flags & LOOKUP_NO_EVAL); > > restore_nameidata(); > > putname(name); > > return error; > > diff --git a/fs/namespace.c b/fs/namespace.c > > index a677b59efd74..e5de0e372df2 100644 > > --- a/fs/namespace.c > > +++ b/fs/namespace.c > > @@ -1640,6 +1640,8 @@ int ksys_umount(char __user *name, int flags) > > if (!(flags & UMOUNT_NOFOLLOW)) > > lookup_flags |= LOOKUP_FOLLOW; > > > > + lookup_flags |= LOOKUP_NO_EVAL; > > + > > retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path); > > if (retval) > > goto out; > > diff --git a/include/linux/audit.h b/include/linux/audit.h > > index a625c29a2ea2..5d914b534536 100644 > > --- a/include/linux/audit.h > > +++ b/include/linux/audit.h > > @@ -25,6 +25,7 @@ > > > > #include <linux/sched.h> > > #include <linux/ptrace.h> > > +#include <linux/namei.h> /* LOOKUP_* */ > > #include <uapi/linux/audit.h> > > > > #define AUDIT_INO_UNSET ((unsigned long)-1) > > @@ -225,6 +226,7 @@ extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1, > > > > #define AUDIT_INODE_PARENT 1 /* dentry represents the parent */ > > #define AUDIT_INODE_HIDDEN 2 /* audit record should be hidden */ > > +#define AUDIT_INODE_NOEVAL 4 /* audit record incomplete */ > > extern void __audit_inode(struct filename *name, const struct dentry *dentry, > > unsigned int flags); > > extern void __audit_file(const struct file *); > > @@ -285,12 +287,15 @@ static inline void audit_getname(struct filename *name) > > } > > static inline void audit_inode(struct filename *name, > > const struct dentry *dentry, > > - unsigned int parent) { > > + unsigned int flags) { > > if (unlikely(!audit_dummy_context())) { > > - unsigned int flags = 0; > > - if (parent) > > - flags |= AUDIT_INODE_PARENT; > > - __audit_inode(name, dentry, flags); > > + unsigned int aflags = 0; > > + > > + if (flags & LOOKUP_PARENT) > > + aflags |= AUDIT_INODE_PARENT; > > + if (flags & LOOKUP_NO_EVAL) > > + aflags |= AUDIT_INODE_NOEVAL; > > + __audit_inode(name, dentry, aflags); > > } > > } > > static inline void audit_file(struct file *file) > > diff --git a/include/linux/namei.h b/include/linux/namei.h > > index a78606e8e3df..9138b4471dbf 100644 > > --- a/include/linux/namei.h > > +++ b/include/linux/namei.h > > @@ -24,6 +24,8 @@ > > * - internal "there are more path components" flag > > * - dentry cache is untrusted; force a real lookup > > * - suppress terminal automount > > + * - skip revalidation > > + * - don't fetch xattrs on audit_inode > > */ > > #define LOOKUP_FOLLOW 0x0001 > > #define LOOKUP_DIRECTORY 0x0002 > > @@ -33,6 +35,7 @@ > > #define LOOKUP_REVAL 0x0020 > > #define LOOKUP_RCU 0x0040 > > #define LOOKUP_NO_REVAL 0x0080 > > +#define LOOKUP_NO_EVAL 0x0100 > > > > /* > > * Intent data > > diff --git a/kernel/audit.c b/kernel/audit.c > > index ca55ccb46b76..45d5131943eb 100644 > > --- a/kernel/audit.c > > +++ b/kernel/audit.c > > @@ -2081,6 +2081,10 @@ void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) > > > > static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) > > { > > + if (name->fcap_ver == -1) { > > + audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); > > + return; > > + } > > audit_log_cap(ab, "cap_fp", &name->fcap.permitted); > > audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); > > audit_log_format(ab, " cap_fe=%d cap_fver=%x", > > @@ -2111,7 +2115,7 @@ static inline int audit_copy_fcaps(struct audit_names *name, > > > > /* Copy inode data into an audit_names. */ > > void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, > > - struct inode *inode) > > + struct inode *inode, unsigned int flags) > > { > > name->ino = inode->i_ino; > > name->dev = inode->i_sb->s_dev; > > @@ -2120,6 +2124,10 @@ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, > > name->gid = inode->i_gid; > > name->rdev = inode->i_rdev; > > security_inode_getsecid(inode, &name->osid); > > + if (flags & AUDIT_INODE_NOEVAL) { > > + name->fcap_ver = -1; > > + return; > > + } > > I'm not in love with the -1 sentinel, especially without a cast in > front of it (style nit I suppose), but I love the idea of adding > another flag to audit_names even more. Since it looks like the > version portion of cpu_vfs_cap_data.magic_etc is limited to eight bits > I suppose we could break up fcap_ver and use some of the 32 bits for > our own flags. Not sure I like that option any more than the others. Would you prefer 0xFFFFFFFF, or 0xFF (assuming it somehow needs to be compatible with the shifted revision mask), or even 0xFFFFFF00 to avoid using those 8 bits? As far as I know, only one bit of the original 24 magic_etc flag bits is used and that is for the fE (file Effective) bit. > I'm also beginning to wonder why we don't just include the fcaps > version info in the audit_cap_data struct; I can't think of a reason > why you would ever want to know one without the other. Thoughts? I wondered that myself... struct audit_cap_data is also used in audit_context.capset where it has no need of the version since it is storing process caps (and the effective field is a union with fE) and in audit_context.aux where it is chained in as audit_aux_data_bprm_fcaps with three instances of audit_cap_data but only one version. We could just keep fcap_ver and fE in the original magic_etc and use a high order bit of the VFS_CAP_FLAGS_MASK... Is it worth changing?

Don't fetch fcaps when umount2 is called to avoid a process hang while it waits for the missing resource to (possibly never) re-appear. Note the comment above user_path_mountpoint_at(): * A umount is a special case for path walking. We're not actually interested * in the inode in this situation, and ESTALE errors can be a problem. We * simply want track down the dentry and vfsmount attached at the mountpoint * and avoid revalidating the last component. This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. Please see the github issue tracker https://github.com/linux-audit/audit-kernel/issues/100 Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; --- fs/namei.c | 2 +- fs/namespace.c | 2 ++ include/linux/audit.h | 15 ++++++++++----- include/linux/namei.h | 3 +++ kernel/audit.c | 10 +++++++++- kernel/audit.h | 2 +- kernel/auditsc.c | 6 +++--- 7 files changed, 29 insertions(+), 11 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 914178cdbe94..87d7710a2e1d 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2720,7 +2720,7 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags, if (unlikely(error == -ESTALE)) error = path_mountpoint(&nd, flags | LOOKUP_REVAL, path); if (likely(!error)) - audit_inode(name, path->dentry, 0); + audit_inode(name, path->dentry, flags & LOOKUP_NO_EVAL); restore_nameidata(); putname(name); return error; diff --git a/fs/namespace.c b/fs/namespace.c index a677b59efd74..e5de0e372df2 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1640,6 +1640,8 @@ int ksys_umount(char __user *name, int flags) if (!(flags & UMOUNT_NOFOLLOW)) lookup_flags |= LOOKUP_FOLLOW; + lookup_flags |= LOOKUP_NO_EVAL; + retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path); if (retval) goto out; diff --git a/include/linux/audit.h b/include/linux/audit.h index a625c29a2ea2..5d914b534536 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -25,6 +25,7 @@ #include <linux/sched.h> #include <linux/ptrace.h> +#include <linux/namei.h> /* LOOKUP_* */ #include <uapi/linux/audit.h> #define AUDIT_INO_UNSET ((unsigned long)-1) @@ -225,6 +226,7 @@ extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1, #define AUDIT_INODE_PARENT 1 /* dentry represents the parent */ #define AUDIT_INODE_HIDDEN 2 /* audit record should be hidden */ +#define AUDIT_INODE_NOEVAL 4 /* audit record incomplete */ extern void __audit_inode(struct filename *name, const struct dentry *dentry, unsigned int flags); extern void __audit_file(const struct file *); @@ -285,12 +287,15 @@ static inline void audit_getname(struct filename *name) } static inline void audit_inode(struct filename *name, const struct dentry *dentry, - unsigned int parent) { + unsigned int flags) { if (unlikely(!audit_dummy_context())) { - unsigned int flags = 0; - if (parent) - flags |= AUDIT_INODE_PARENT; - __audit_inode(name, dentry, flags); + unsigned int aflags = 0; + + if (flags & LOOKUP_PARENT) + aflags |= AUDIT_INODE_PARENT; + if (flags & LOOKUP_NO_EVAL) + aflags |= AUDIT_INODE_NOEVAL; + __audit_inode(name, dentry, aflags); } } static inline void audit_file(struct file *file) diff --git a/include/linux/namei.h b/include/linux/namei.h index a78606e8e3df..9138b4471dbf 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -24,6 +24,8 @@ * - internal "there are more path components" flag * - dentry cache is untrusted; force a real lookup * - suppress terminal automount + * - skip revalidation + * - don't fetch xattrs on audit_inode */ #define LOOKUP_FOLLOW 0x0001 #define LOOKUP_DIRECTORY 0x0002 @@ -33,6 +35,7 @@ #define LOOKUP_REVAL 0x0020 #define LOOKUP_RCU 0x0040 #define LOOKUP_NO_REVAL 0x0080 +#define LOOKUP_NO_EVAL 0x0100 /* * Intent data diff --git a/kernel/audit.c b/kernel/audit.c index ca55ccb46b76..45d5131943eb 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2081,6 +2081,10 @@ void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) { + if (name->fcap_ver == -1) { + audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); + return; + } audit_log_cap(ab, "cap_fp", &name->fcap.permitted); audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); audit_log_format(ab, " cap_fe=%d cap_fver=%x", @@ -2111,7 +2115,7 @@ static inline int audit_copy_fcaps(struct audit_names *name, /* Copy inode data into an audit_names. */ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, - struct inode *inode) + struct inode *inode, unsigned int flags) { name->ino = inode->i_ino; name->dev = inode->i_sb->s_dev; @@ -2120,6 +2124,10 @@ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, name->gid = inode->i_gid; name->rdev = inode->i_rdev; security_inode_getsecid(inode, &name->osid); + if (flags & AUDIT_INODE_NOEVAL) {

+ name->fcap_ver = -1; + return; + } audit_copy_fcaps(name, dentry); } diff --git a/kernel/audit.h b/kernel/audit.h index 6ffb70575082..25ab276be8e5 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -214,7 +214,7 @@ struct audit_context { extern void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, - struct inode *inode); + struct inode *inode, unsigned int flags); extern void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap); extern void audit_log_name(struct audit_context *context, diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 3d05d5fc6240..9a1257afc4d4 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1853,7 +1853,7 @@ void __audit_inode(struct filename *name, const struct dentry *dentry, n->type = AUDIT_TYPE_NORMAL; } handle_path(dentry); - audit_copy_inode(n, dentry, inode); + audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL); } void __audit_file(const struct file *file) @@ -1952,7 +1952,7 @@ void __audit_inode_child(struct inode *parent, n = audit_alloc_name(context, AUDIT_TYPE_PARENT); if (!n) return; - audit_copy_inode(n, NULL, parent); + audit_copy_inode(n, NULL, parent, 0); } if (!found_child) { @@ -1971,7 +1971,7 @@ void __audit_inode_child(struct inode *parent, } if (inode) - audit_copy_inode(found_child, dentry, inode); + audit_copy_inode(found_child, dentry, inode, 0); else found_child->ino = AUDIT_INO_UNSET; } -- 1.8.3.1

On Fri, Feb 1, 2019 at 3:42 PM Nathan Chancellor <natechancellor(a)gmail.com&gt; wrote: > On Wed, Jan 23, 2019 at 01:35:00PM -0500, Richard Guy Briggs wrote: > > Don't fetch fcaps when umount2 is called to avoid a process hang while > > it waits for the missing resource to (possibly never) re-appear. > > > > Note the comment above user_path_mountpoint_at(): > > * A umount is a special case for path walking. We're not actually interested > > * in the inode in this situation, and ESTALE errors can be a problem. We > > * simply want track down the dentry and vfsmount attached at the mountpoint > > * and avoid revalidating the last component. > > > > This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. > > > > Please see the github issue tracker > > https://github.com/linux-audit/audit-kernel/issues/100 > > > > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > > --- > > fs/namei.c | 2 +- > > fs/namespace.c | 2 ++ > > include/linux/audit.h | 15 ++++++++++----- > > include/linux/namei.h | 3 +++ > > kernel/audit.c | 10 +++++++++- > > kernel/audit.h | 2 +- > > kernel/auditsc.c | 6 +++--- > > 7 files changed, 29 insertions(+), 11 deletions(-) ... > > /* Copy inode data into an audit_names. */ > > void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, > > - struct inode *inode) > > + struct inode *inode, unsigned int flags) > > { > > name->ino = inode->i_ino; > > name->dev = inode->i_sb->s_dev; > > @@ -2120,6 +2124,10 @@ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, > > name->gid = inode->i_gid; > > name->rdev = inode->i_rdev; > > security_inode_getsecid(inode, &name->osid); > > + if (flags & AUDIT_INODE_NOEVAL) { > > I don't know if this has been reported or if I am missing something but > on next-20190201, this line causes an error with arm allyesconfig (as > CONFIG_AUDITSYCALL doesn't get selected): ... > CC kernel/audit.o > kernel/audit.c: In function 'audit_copy_inode': > kernel/audit.c:2130:14: error: 'AUDIT_INODE_NOEVAL' undeclared (first use in this function); did you mean 'AUDIT_TYPE_NORMAL'? > if (flags & AUDIT_INODE_NOEVAL) { > ^~~~~~~~~~~~~~~~~~ > AUDIT_TYPE_NORMAL > kernel/audit.c:2130:14: note: each undeclared identifier is reported only once for each function it appears in > make[2]: *** [scripts/Makefile.build:277: kernel/audit.o] Error 1 > make[1]: *** [Makefile:1699: kernel/audit.o] Error 2 > make: *** [Makefile:296: __build_one_by_one] Error 2 I hadn't seen this reported to the audit list yet, thanks for letting us now.

Richard, please submit a patch to fix this ASAP. Looking at this, the obvious fix is to move audit_copy_inode() to auditsc.c, but I'm not sure if that itself is going to cause problems (it doesn't look like it). Actually, thinking out loud, I wonder if we shouldn't move audit_log_cap(), audit_log_fcaps(), audit_copy_fcaps(), and audit_log_name() too?

paul moore

On 2019-02-01 16:05, Paul Moore wrote: > On Fri, Feb 1, 2019 at 3:42 PM Nathan Chancellor > <natechancellor(a)gmail.com&gt; wrote: > > On Wed, Jan 23, 2019 at 01:35:00PM -0500, Richard Guy Briggs wrote: > > > Don't fetch fcaps when umount2 is called to avoid a process hang while > > > it waits for the missing resource to (possibly never) re-appear. > > > > > > Note the comment above user_path_mountpoint_at(): > > > * A umount is a special case for path walking. We're not actually interested > > > * in the inode in this situation, and ESTALE errors can be a problem. We > > > * simply want track down the dentry and vfsmount attached at the mountpoint > > > * and avoid revalidating the last component. > > > > > > This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. > > > > > > Please see the github issue tracker > > > https://github.com/linux-audit/audit-kernel/issues/100 > > > > > > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; > > > --- > > > fs/namei.c | 2 +- > > > fs/namespace.c | 2 ++ > > > include/linux/audit.h | 15 ++++++++++----- > > > include/linux/namei.h | 3 +++ > > > kernel/audit.c | 10 +++++++++- > > > kernel/audit.h | 2 +- > > > kernel/auditsc.c | 6 +++--- > > > 7 files changed, 29 insertions(+), 11 deletions(-) > > ... > > > > /* Copy inode data into an audit_names. */ > > > void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, > > > - struct inode *inode) > > > + struct inode *inode, unsigned int flags) > > > { > > > name->ino = inode->i_ino; > > > name->dev = inode->i_sb->s_dev; > > > @@ -2120,6 +2124,10 @@ void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, > > > name->gid = inode->i_gid; > > > name->rdev = inode->i_rdev; > > > security_inode_getsecid(inode, &name->osid); > > > + if (flags & AUDIT_INODE_NOEVAL) { > > > > I don't know if this has been reported or if I am missing something but > > on next-20190201, this line causes an error with arm allyesconfig (as > > CONFIG_AUDITSYCALL doesn't get selected): > > ... > > > CC kernel/audit.o > > kernel/audit.c: In function 'audit_copy_inode': > > kernel/audit.c:2130:14: error: 'AUDIT_INODE_NOEVAL' undeclared (first use in this function); did you mean 'AUDIT_TYPE_NORMAL'? > > if (flags & AUDIT_INODE_NOEVAL) { > > ^~~~~~~~~~~~~~~~~~ > > AUDIT_TYPE_NORMAL > > kernel/audit.c:2130:14: note: each undeclared identifier is reported only once for each function it appears in > > make[2]: *** [scripts/Makefile.build:277: kernel/audit.o] Error 1 > > make[1]: *** [Makefile:1699: kernel/audit.o] Error 2 > > make: *** [Makefile:296: __build_one_by_one] Error 2 > > I hadn't seen this reported to the audit list yet, thanks for letting us now. Thanks Nathan for the report. > Richard, please submit a patch to fix this ASAP. Looking at this, the > obvious fix is to move audit_copy_inode() to auditsc.c, but I'm not > sure if that itself is going to cause problems (it doesn't look like > it). Actually, thinking out loud, I wonder if we shouldn't move > audit_log_cap(), audit_log_fcaps(), audit_copy_fcaps(), and > audit_log_name() too? They have all been moved in ghak105 v2 patch 2 which is in your queue. Lemme think if there is a quicker simpler solution for this patch. That ghak105 v2.patch2 will have a number of merge conflicts and I've already sorted those out, so I'm willing to post a respin (v3) of it to make your life easier. (audit_log_key() should also be moved, now that I check...)

> paul moore - RGB