TencentOS-kernel/security
Vasily Averin 8728648709 selinux: sel_avc_get_stat_idx should increase position index
[ Upstream commit 8d269a8e2a8f0bca89022f4ec98de460acb90365 ]

If seq_file .next function does not change position index,
read after some lseek can generate unexpected output.

$ dd if=/sys/fs/selinux/avc/cache_stats # usual output
lookups hits misses allocations reclaims frees
817223 810034 7189 7189 6992 7037
1934894 1926896 7998 7998 7632 7683
1322812 1317176 5636 5636 5456 5507
1560571 1551548 9023 9023 9056 9115
0+1 records in
0+1 records out
189 bytes copied, 5,1564e-05 s, 3,7 MB/s

$# read after lseek to midle of last line
$ dd if=/sys/fs/selinux/avc/cache_stats bs=180 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
056 9115   <<<< end of last line
1560571 1551548 9023 9023 9056 9115  <<< whole last line once again
0+1 records in
0+1 records out
45 bytes copied, 8,7221e-05 s, 516 kB/s

$# read after lseek beyond  end of of file
$ dd if=/sys/fs/selinux/avc/cache_stats bs=1000 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
1560571 1551548 9023 9023 9056 9115  <<<< generates whole last line
0+1 records in
0+1 records out
36 bytes copied, 9,0934e-05 s, 396 kB/s

https://bugzilla.kernel.org/show_bug.cgi?id=206283

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:36:51 +08:00
..
apparmor apparmor: ensure that dfa state tables have entries 2021-03-16 16:32:02 +08:00
integrity ima: Have the LSM free its audit rule 2021-03-16 16:33:35 +08:00
keys mm: add kvfree_sensitive() for freeing sensitive data objects 2021-03-16 16:28:58 +08:00
loadpin Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
lockdown lockdown: Allow unprivileged users to see lockdown status 2021-03-16 16:29:19 +08:00
safesetid Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
selinux selinux: sel_avc_get_stat_idx should increase position index 2021-03-16 16:36:51 +08:00
smack Smack: prevent underflow in smk_set_cipso() 2021-03-16 16:33:40 +08:00
tomoyo Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
yama Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kconfig Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kconfig.hardening Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Makefile Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
commoncap.c exec: Always set cap_ambient in cap_bprm_set_creds 2021-03-16 16:28:35 +08:00
device_cgroup.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
inode.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
lsm_audit.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
min_addr.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
security.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00