kernel.git/security/apparmor/apparmorfs.c, branch linux-4.19.y

apparmor: fix possible NULL pointer dereference

2024-09-12T09:02:50Z

[ Upstream commit 3dd384108d53834002be5630132ad5c3f32166ad ] profile->parent->dents[AAFS_PROF_DIR] could be NULL only if its parent is made from __create_missing_ancestors(..) and 'ent->old' is NULL in aa_replace_profiles(..). In that case, it must return an error code and the code, -ENOENT represents its state that the path of its parent is not existed yet. BUG: kernel NULL pointer dereference, address: 0000000000000030 PGD 0 P4D 0 PREEMPT SMP PTI CPU: 4 PID: 3362 Comm: apparmor_parser Not tainted 6.8.0-24-generic #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 RIP: 0010:aafs_create.constprop.0+0x7f/0x130 Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0 Call Trace: ? show_regs+0x6d/0x80 ? __die+0x24/0x80 ? page_fault_oops+0x99/0x1b0 ? kernelmode_fixup_or_oops+0xb2/0x140 ? __bad_area_nosemaphore+0x1a5/0x2c0 ? find_vma+0x34/0x60 ? bad_area_nosemaphore+0x16/0x30 ? do_user_addr_fault+0x2a2/0x6b0 ? exc_page_fault+0x83/0x1b0 ? asm_exc_page_fault+0x27/0x30 ? aafs_create.constprop.0+0x7f/0x130 ? aafs_create.constprop.0+0x51/0x130 __aafs_profile_mkdir+0x3d6/0x480 aa_replace_profiles+0x83f/0x1270 policy_update+0xe3/0x180 profile_load+0xbc/0x150 ? rw_verify_area+0x47/0x140 vfs_write+0x100/0x480 ? __x64_sys_openat+0x55/0xa0 ? syscall_exit_to_user_mode+0x86/0x260 ksys_write+0x73/0x100 __x64_sys_write+0x19/0x30 x64_sys_call+0x7e/0x25c0 do_syscall_64+0x7f/0x180 entry_SYSCALL_64_after_hwframe+0x78/0x80 RIP: 0033:0x7be9f211c574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007ffd26f2b8c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00005d504415e200 RCX: 00007be9f211c574 RDX: 0000000000001fc1 RSI: 00005d504418bc80 RDI: 0000000000000004 RBP: 0000000000001fc1 R08: 0000000000001fc1 R09: 0000000080000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00005d504418bc80 R13: 0000000000000004 R14: 00007ffd26f2b9b0 R15: 00007ffd26f2ba30 Modules linked in: snd_seq_dummy snd_hrtimer qrtr snd_hda_codec_generic snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device i2c_i801 snd_timer i2c_smbus qxl snd soundcore drm_ttm_helper lpc_ich ttm joydev input_leds serio_raw mac_hid binfmt_misc msr parport_pc ppdev lp parport efi_pstore nfnetlink dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid ahci libahci psmouse virtio_rng xhci_pci xhci_pci_renesas CR2: 0000000000000030 ---[ end trace 0000000000000000 ]--- RIP: 0010:aafs_create.constprop.0+0x7f/0x130 Code: 4c 63 e0 48 83 c4 18 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 45 31 d2 c3 cc cc cc cc <4d> 8b 55 30 4d 8d ba a0 00 00 00 4c 89 55 c0 4c 89 ff e8 7a 6a ae RSP: 0018:ffffc9000b2c7c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000000041ed RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000b2c7cd8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82baac10 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007be9f22cf740(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000030 CR3: 0000000134b08000 CR4: 00000000000006f0 Signed-off-by: Leesoo Ahn Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmor: fix a memleak in multi_transaction_new()

2023-01-18T10:30:20Z

[ Upstream commit c73275cf6834787ca090317f1d20dbfa3b7f05aa ] In multi_transaction_new(), the variable t is not freed or passed out on the failure of copy_from_user(t->data, buf, size), which could lead to a memleak. Fix this bug by adding a put_multi_transaction(t) in the error path. Fixes: 1dea3b41e84c5 ("apparmor: speed up transactional queries") Signed-off-by: Gaosheng Cui Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmor: Fix memleak in aa_simple_write_to_buffer()

2022-08-25T09:15:36Z

commit 417ea9fe972d2654a268ad66e89c8fcae67017c3 upstream. When copy_from_user failed, the memory is freed by kvfree. however the management struct and data blob are allocated independently, so only kvfree(data) cause a memleak issue here. Use aa_put_loaddata(data) to fix this issue. Fixes: a6a52579e52b5 ("apparmor: split load data into management struct and data blob") Signed-off-by: Xiu Jianfeng Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman

apparmor: remove duplicate macro list_entry_is_head()

2021-09-26T11:39:47Z

commit 9801ca279ad37f72f71234fa81722afd95a3f997 upstream. Strangely I hadn't had noticed the existence of the list_entry_is_head() in apparmor code when added the same one in the list.h. Luckily it's fully identical and didn't break builds. In any case we don't need a duplicate anymore, thus remove it from apparmor code. Link: https://lkml.kernel.org/r/20201208100639.88182-1-andriy.shevchenko@linux.intel.com Fixes: e130816164e244 ("include/linux/list.h: add a macro to test if entry is pointing to the head") Signed-off-by: Andy Shevchenko Acked-by: John Johansen Cc: James Morris Cc: "Serge E . Hallyn " Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Nobuhiro Iwamatsu (CIP) Signed-off-by: Greg Kroah-Hartman

apparmor: Fix aa_label refcnt leak in policy_update

2020-05-27T15:37:37Z

commit c6b39f070722ea9963ffe756bfe94e89218c5e63 upstream. policy_update() invokes begin_current_label_crit_section(), which returns a reference of the updated aa_label object to "label" with increased refcount. When policy_update() returns, "label" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of policy_update(). When aa_may_manage_policy() returns not NULL, the refcnt increased by begin_current_label_crit_section() is not decreased, causing a refcnt leak. Fix this issue by jumping to "end_section" label when aa_may_manage_policy() returns not NULL. Fixes: 5ac8c355ae00 ("apparmor: allow introspecting the loaded policy pre internal transform") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman

apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock

2020-01-09T09:19:02Z

commit 8c62ed27a12c00e3db1c9f04bc0f272bdbb06734 upstream. aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a context protected by an rcu_read_lock. This can not be done as vfs_getxattr_alloc() may sleep regardles of the gfp_t value being passed to it. Fix this by breaking the rcu_read_lock on the policy search when the xattr match feature is requested and restarting the search if a policy changes occur. Fixes: 8e51f9087f40 ("apparmor: Add support for attaching profiles via xattr, presence and value") Reported-by: Jia-Ju Bai Reported-by: Al Viro Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman

apparmor: delete the dentry in aafs_remove() to avoid a leak

2019-12-05T08:21:19Z

[ Upstream commit 201218e4d3dfa1346e30997f48725acce3f26d01 ] Although the apparmorfs dentries are always dropped from the dentry cache when the usage count drops to zero, there is no guarantee that this will happen in aafs_remove(), as another thread might still be using it. In this scenario, this means that the dentry will temporarily continue to appear in the results of lookups, even after the call to aafs_remove(). In the case of removal of a profile - it also causes simple_rmdir() on the profile directory to fail, as the directory won't be empty until the usage counts of all child dentries have decreased to zero. This results in the dentry for the profile directory leaking and appearing empty in the file system tree forever. Signed-off-by: Chris Coulson Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmorfs: fix use-after-free on symlink traversal

2019-05-25T16:23:42Z

[ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ] symlink body shouldn't be freed without an RCU delay. Switch apparmorfs to ->destroy_inode() and use of call_rcu(); free both the inode and symlink body in the callback. Signed-off-by: Al Viro Signed-off-by: Sasha Levin

apparmor: Fully initialize aa_perms struct when answering userspace query

2018-07-19T23:29:13Z

Fully initialize the aa_perms struct in profile_query_cb() to avoid the potential of using an uninitialized struct member's value in a response to a query from userspace. Detected by CoverityScan CID#1415126 ("Uninitialized scalar variable") Fixes: 4f3b3f2d79a4 ("apparmor: add profile permission query ability") Signed-off-by: Tyler Hicks Acked-by: Serge Hallyn Signed-off-by: John Johansen

Merge tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

2018-04-13T22:38:53Z

Pull apparmor updates from John Johansen: "Features: - add base infrastructure for socket mediation. ABI bump and additional checks to ensure only v8 compliant policy uses socket af mediation. - improve and cleanup dfa verification - improve profile attachment logic - improve overlapping expression handling - add the xattr matching to the attachment logic - improve signal mediation handling with stacked labels - improve handling of no_new_privs in a label stack Cleanups and changes: - use dfa to parse string split - bounded version of label_parse - proper line wrap nulldfa.in - split context out into task and cred naming to better match usage - simplify code in aafs Bug fixes: - fix display of .ns_name for containers - fix resource audit messages when auditing peer - fix logging of the existence test for signals - fix resource audit messages when auditing peer - fix display of .ns_name for containers - fix an error code in verify_table_headers() - fix memory leak on buffer on error exit path - fix error returns checks by making size a ssize_t" * tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (36 commits) apparmor: fix memory leak on buffer on error exit path apparmor: fix dangling symlinks to policy rawdata after replacement apparmor: Fix an error code in verify_table_headers() apparmor: fix error returns checks by making size a ssize_t apparmor: update MAINTAINERS file git and wiki locations apparmor: remove POLICY_MEDIATES_SAFE apparmor: add base infastructure for socket mediation apparmor: improve overlapping domain attachment resolution apparmor: convert attaching profiles via xattrs to use dfa matching apparmor: Add support for attaching profiles via xattr, presence and value apparmor: cleanup: simplify code to get ns symlink name apparmor: cleanup create_aafs() error path apparmor: dfa split verification of table headers apparmor: dfa add support for state differential encoding apparmor: dfa move character match into a macro apparmor: update domain transitions that are subsets of confinement at nnp apparmor: move context.h to cred.h apparmor: move task related defines and fns to task.X files apparmor: cleanup, drop unused fn __aa_task_is_confined() apparmor: cleanup fixup description of aa_replace_profiles ...