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GONG, Ruiqi abe3c63144 selinux: enable use of both GFP_KERNEL and GFP_ATOMIC in convert_context() 
The following warning was triggered on a hardware environment:

  SELinux: Converting 162 SID table entries...
  BUG: sleeping function called from invalid context at
       __might_sleep+0x60/0x74 0x0
  in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 5943, name: tar
  CPU: 7 PID: 5943 Comm: tar Tainted: P O 5.10.0 #1
  Call trace:
   dump_backtrace+0x0/0x1c8
   show_stack+0x18/0x28
   dump_stack+0xe8/0x15c
   ___might_sleep+0x168/0x17c
   __might_sleep+0x60/0x74
   __kmalloc_track_caller+0xa0/0x7dc
   kstrdup+0x54/0xac
   convert_context+0x48/0x2e4
   sidtab_context_to_sid+0x1c4/0x36c
   security_context_to_sid_core+0x168/0x238
   security_context_to_sid_default+0x14/0x24
   inode_doinit_use_xattr+0x164/0x1e4
   inode_doinit_with_dentry+0x1c0/0x488
   selinux_d_instantiate+0x20/0x34
   security_d_instantiate+0x70/0xbc
   d_splice_alias+0x4c/0x3c0
   ext4_lookup+0x1d8/0x200 [ext4]
   __lookup_slow+0x12c/0x1e4
   walk_component+0x100/0x200
   path_lookupat+0x88/0x118
   filename_lookup+0x98/0x130
   user_path_at_empty+0x48/0x60
   vfs_statx+0x84/0x140
   vfs_fstatat+0x20/0x30
   __se_sys_newfstatat+0x30/0x74
   __arm64_sys_newfstatat+0x1c/0x2c
   el0_svc_common.constprop.0+0x100/0x184
   do_el0_svc+0x1c/0x2c
   el0_svc+0x20/0x34
   el0_sync_handler+0x80/0x17c
   el0_sync+0x13c/0x140
  SELinux: Context system_u:object_r:pssp_rsyslog_log_t:s0:c0 is
           not valid (left unmapped).

It was found that within a critical section of spin_lock_irqsave in
sidtab_context_to_sid(), convert_context() (hooked by
sidtab_convert_params.func) might cause the process to sleep via
allocating memory with GFP_KERNEL, which is problematic.

As Ondrej pointed out [1], convert_context()/sidtab_convert_params.func
has another caller sidtab_convert_tree(), which is okay with GFP_KERNEL.
Therefore, fix this problem by adding a gfp_t argument for
convert_context()/sidtab_convert_params.func and pass GFP_KERNEL/_ATOMIC
properly in individual callers.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20221018120111.1474581-1-gongruiqi1@huawei.com/ [1]
Reported-by: Tan Ninghao <tanninghao1@huawei.com>
Fixes: ee1a84fdfe ("selinux: overhaul sidtab to fix bug and improve performance")
Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: wrap long BUG() output lines, tweak subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-10-19 09:55:53 -04:00
..
apparmor ->getprocattr(): attribute name is const char *, TYVM... 2022-09-01 17:34:39 -04:00
bpf
integrity fs.acl.rework.prep.v6.1 2022-10-03 19:48:54 -07:00
keys tpmdd updates for Linux v6.1-rc1 2022-10-10 13:09:33 -07:00
landlock landlock: Fix documentation style 2022-09-29 18:43:04 +02:00
loadpin LoadPin: Require file with verity root digests to have a header 2022-09-07 16:37:27 -07:00
lockdown lockdown: ratelimit denial messages 2022-09-14 07:37:50 -04:00
safesetid LSM: SafeSetID: Add setgroups() security policy handling 2022-07-15 18:24:42 +00:00
selinux selinux: enable use of both GFP_KERNEL and GFP_ATOMIC in convert_context() 2022-10-19 09:55:53 -04:00
smack whack-a-mole: constifying struct path * 2022-10-06 17:31:02 -07:00
tomoyo tomoyo: struct path it might get from LSM callers won't have NULL dentry or mnt 2022-08-21 11:50:42 -04:00
yama
commoncap.c
device_cgroup.c bpf: Make BPF_PROG_RUN_ARRAY return -err instead of allow boolean 2022-01-19 12:51:30 -08:00
inode.c
Kconfig x86/retbleed: Add fine grained Kconfig knobs 2022-06-29 17:43:41 +02:00
Kconfig.hardening - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
lsm_audit.c lsm: clean up redundant NULL pointer check 2022-08-15 22:44:01 -04:00
Makefile
min_addr.c
security.c powerpc updates for 6.1 2022-10-09 14:05:15 -07:00