Currently, if we call getname() on a userland string more than once,
we'll get multiple copies of the string and multiple audit_names
records.
Add a function that will allow the audit_names code to satisfy getname
requests using info from the audit_names list, avoiding a new allocation
and audit_names records.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.
For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.
This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.
Later, we'll add other information to the struct as it becomes
convenient.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
First, it's incorrect to call putname() after __getname_gfp() since the
bare __getname_gfp() call skips the auditing code, while putname()
doesn't.
mount_block_root allocates a PATH_MAX buffer via __getname_gfp, and then
calls get_fs_names to fill the buffer. That function can call
get_filesystem_list which assumes that that buffer is a full page in
size. On arches where PAGE_SIZE != 4k, then this could potentially
overrun.
In practice, it's hard to imagine the list of filesystem names even
approaching 4k, but it's best to be safe. Just allocate a page for this
purpose instead.
With this, we can also remove the __getname_gfp() definition since there
are no more callers.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In order to accomodate retrying path-based syscalls, we need to add a
new "type" argument to audit_inode_child. This will tell us whether
we're looking for a child entry that represents a create or a delete.
If we find a parent, don't automatically assume that we need to create a
new entry. Instead, use the information we have to try to find an
existing entry first. Update it if one is found and create a new one if
not.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In the cases where we already know the length of the parent, pass it as
a parm so we don't need to recompute it. In the cases where we don't
know the length, pass in AUDIT_NAME_FULL (-1) to indicate that it should
be determined.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Currently, this gets set mostly by happenstance when we call into
audit_inode_child. While that might be a little more efficient, it seems
wrong. If the syscall ends up failing before audit_inode_child ever gets
called, then you'll have an audit_names record that shows the full path
but has the parent inode info attached.
Fix this by passing in a parent flag when we call audit_inode that gets
set to the value of LOOKUP_PARENT. We can then fix up the pathname for
the audit entry correctly from the get-go.
While we're at it, clean up the no-op macro for audit_inode in the
!CONFIG_AUDITSYSCALL case.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For now, we just have two possibilities:
UNKNOWN: for a new audit_names record that we don't know anything about yet
NORMAL: for everything else
In later patches, we'll add other types so we can distinguish and update
records created under different circumstances.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Most of the callers get called with an inode and dentry in the reverse
order. The compiler then has to reshuffle the arg registers and/or
stack in order to pass them on to audit_inode_child.
Reverse those arguments for a micro-optimization.
Reported-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If name is NULL then the condition in the loop will never be true. Also,
with this change, we can eliminate the check for n->name == NULL since
the equivalence check will never be true if it is.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
As best I can tell, whenever retval == 0, nd->path.dentry and nd->inode
are also non-NULL. Eliminate those checks and the superfluous
audit_context check.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull pile 2 of vfs updates from Al Viro:
"Stuff in this one - assorted fixes, lglock tidy-up, death to
lock_super().
There'll be a VFS pile tomorrow (with patches from Jeff Layton,
sanitizing getname() and related parts of audit and preparing for
ESTALE fixes), but I'd rather push the stuff in this one ASAP - some
of the bugs closed here are quite unpleasant."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: bogus warnings in fs/namei.c
consitify do_mount() arguments
lglock: add DEFINE_STATIC_LGLOCK()
lglock: make the per_cpu locks static
lglock: remove unused DEFINE_LGLOCK_LOCKDEP()
MAX_LFS_FILESIZE definition for 64bit needs LL...
tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking
vfs: drop lock/unlock super
ufs: drop lock/unlock super
sysv: drop lock/unlock super
hpfs: drop lock/unlock super
fat: drop lock/unlock super
ext3: drop lock/unlock super
exofs: drop lock/unlock super
dup3: Return an error when oldfd == newfd.
fs: handle failed audit_log_start properly
fs: prevent use after free in auditing when symlink following was denied
Pull pile 2 of execve and kernel_thread unification work from Al Viro:
"Stuff in there: kernel_thread/kernel_execve/sys_execve conversions for
several more architectures plus assorted signal fixes and cleanups.
There'll be more (in particular, real fixes for the alpha
do_notify_resume() irq mess)..."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (43 commits)
alpha: don't open-code trace_report_syscall_{enter,exit}
Uninclude linux/freezer.h
m32r: trim masks
avr32: trim masks
tile: don't bother with SIGTRAP in setup_frame
microblaze: don't bother with SIGTRAP in setup_rt_frame()
mn10300: don't bother with SIGTRAP in setup_frame()
frv: no need to raise SIGTRAP in setup_frame()
x86: get rid of duplicate code in case of CONFIG_VM86
unicore32: remove pointless test
h8300: trim _TIF_WORK_MASK
parisc: decide whether to go to slow path (tracesys) based on thread flags
parisc: don't bother looping in do_signal()
parisc: fix double restarts
bury the rest of TIF_IRET
sanitize tsk_is_polling()
bury _TIF_RESTORE_SIGMASK
unicore32: unobfuscate _TIF_WORK_MASK
mips: NOTIFY_RESUME is not needed in TIF masks
mips: merge the identical "return from syscall" per-ABI code
...
Conflicts:
arch/arm/include/asm/thread_info.h
Pull writeback fixes from Fengguang Wu:
"Three trivial writeback fixes"
* 'writeback-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
CPU hotplug, writeback: Don't call writeback_set_ratelimit() too often during hotplug
writeback: correct comment for move_expired_inodes()
backing-dev: use kstrto* in preference to simple_strtoul
Pull kbuild misc changes from Michal Marek:
"In the non-critical part of kbuild, I have
- Some make coccicheck improvements and two new tests
- Support for a cleaner html output in scripts/kernel-doc, named
html5 (no, it does not play videos, yet)
BTW, Randy wants to route further kernel-doc patches through the
kbuild tree."
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
Update SmPL/Coccinelle section of MAINTAINERS
coccicheck: Add the rep+ctxt mode
scripts/coccinelle/tests/odd_ptr_err.cocci: semantic patch for IS_ERR/PTR_ERR inconsistency
scripts/tags.sh: Add magic for pci access functions
scripts/coccinelle: ptr_ret: Add ternary operator version
scripts/kernel-doc: drop maintainer
scripts/kernel-doc: added support for html5
Pull kconfig changes from Michal Marek:
"kconfig in v3.7 is going to
- initialize ncurses only once in menuconfig
- be able to jump to a search result in menuconfig
- change the misnomer oldnoconfig to a more meaningful name
olddefconfig, keeping the old name as alias"
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
kconfig: replace 'oldnoconfig' with 'olddefconfig', and keep the old name as an alias
menuconfig: Assign jump keys per-page instead of globally
menuconfig: Do not open code textbox scroll up/down
menuconfig: Add jump keys to search results
menuconfig: Extend dialog_textbox so that it can return to a scrolled position
menuconfig: Extend dialog_textbox so that it can exit on arbitrary keypresses
menuconfig: Remove superfluous conditionnal
kconfig: document oldnoconfig to what it really does in conf.c
kconfig/mconf.c: revision of curses initialization.
Pull kbuild changes from Michal Marek:
"The main part of kbuild for v3.7 contains:
- Fix for scripts/Makefile.modpost to not choke on a '.ko' substring
in the build directory path
- Two warning fixes (modpost and main Makefile)
- __compiletime_error works also with gcc 4.3
- make tar{gz,bz2,xz}-pkg uses default compression settings instead
of saving as many bytes as possible (this should actually be in the
misc branch, I don't know why I applied it here)."
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
compiler-gcc4.h: correct verion check for __compiletime_error
modpost: Permit .GCC.command.line sections
Kbuild: use normal compression settings for tar*-pkg
scripts/Makefile.modpost: error in finding modules from .mod files.
kbuild: Remove useless warning while appending KCFLAGS
Pull fbdev updates from Florian Tobias Schandinat:
"This includes:
- large updates for OMAP
- basic OMAP5 DSS support for DPI and DSI outputs
- large cleanups and restructuring
- some update to Exynos and da8xx-fb
- removal of the pnx4008 driver (arch removed)
- various other small patches"
Fix up some trivial conflicts (mostly just include line changes, but
also some due to the renaming of the deferred work functions by Tejun).
* tag 'fbdev-updates-for-3.7' of git://github.com/schandinat/linux-2.6: (193 commits)
gbefb: fix compile error
video: mark nuc900fb_map_video_memory as __devinit
video/mx3fb: set .owner to prevent module unloading while being used
video: exynos_dp: use clk_prepare_enable and clk_disable_unprepare
drivers/video/exynos/exynos_mipi_dsi.c: fix error return code
drivers/video/savage/savagefb_driver.c: fix error return code
video: s3c-fb: use clk_prepare_enable and clk_disable_unprepare
da8xx-fb: save and restore LCDC context across suspend/resume cycle
da8xx-fb: add pm_runtime support
video/udlfb: fix line counting in fb_write
OMAPDSS: add missing include for string.h
OMAPDSS: DISPC: Configure color conversion coefficients for writeback
OMAPDSS: DISPC: Add manager like functions for writeback
OMAPDSS: DISPC: Configure writeback FIFOs
OMAPDSS: DISPC: Configure writeback specific parameters in dispc_wb_setup()
OMAPDSS: DISPC: Configure overlay-like parameters in dispc_wb_setup
OMAPDSS: DISPC: Add function to set channel in for writeback
OMAPDSS: DISPC: Don't set chroma resampling bit for writeback
OMAPDSS: DISPC: Downscale chroma if plane is writeback
OMAPDSS: DISPC: Configure input and output sizes for writeback
...
Pull v9fs update from Eric Van Hensbergen.
* tag 'for-linus-merge-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
9P: Fix race between p9_write_work() and p9_fd_request()
9P: Fix race in p9_write_work()
9P: fix test at the end of p9_write_work()
9P: Fix race in p9_read_work()
9p: don't use __getname/__putname for uname/aname
net/9p: Check errno validity
fs/9p: avoid debug OOPS when reading a long symlink
The follow_link() function always initializes its *p argument,
or returns an error, but when building with 'gcc -s', the compiler
gets confused by the __always_inline attribute to the function
and can no longer detect where the cookie was initialized.
The solution is to always initialize the pointer from follow_link,
even in the error path. When building with -O2, this has zero impact
on generated code and adds a single instruction in the error path
for a -Os build on ARM.
Without this patch, building with gcc-4.6 through gcc-4.8 and
CONFIG_CC_OPTIMIZE_FOR_SIZE results in:
fs/namei.c: In function 'link_path_walk':
fs/namei.c:649:24: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized]
fs/namei.c:1544:9: note: 'cookie' was declared here
fs/namei.c: In function 'path_lookupat':
fs/namei.c:649:24: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized]
fs/namei.c:1934:10: note: 'cookie' was declared here
fs/namei.c: In function 'path_openat':
fs/namei.c:649:24: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized]
fs/namei.c:2899:9: note: 'cookie' was declared here
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>