openkylin
/
platform_kernel-5.15
mirror of https://gitee.com/openkylin/platform_kernel-5.15.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

mm/mlock: fix potential imbalanced rlimit ucounts adjustment 

commit 5c2a956c3eea173b2bc89f632507c0eeaebf6c4a upstream.

user_shm_lock forgets to set allowed to 0 when get_ucounts fails.  So
the later user_shm_unlock might do the extra dec_rlimit_ucounts.  Fix
this by resetting allowed to 0.

Link: https://lkml.kernel.org/r/20220310132417.41189-1-linmiaohe@huawei.com
Fixes: d7c9e99aee ("Reimplement RLIMIT_MEMLOCK on top of ucounts")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Herbert van den Bergh <herbert.van.den.bergh@oracle.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Miaohe Lin 2022-03-22 14:44:56 -07:00 committed by Greg Kroah-Hartman
parent acf3e6843a
commit 954c78ed8c
1 changed files with 1 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
mm/mlock.c
View File

@ -837,6 +837,7 @@ int user_shm_lock(size_t size, struct ucounts *ucounts)
} }
if (!get_ucounts(ucounts)) { if (!get_ucounts(ucounts)) {
dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked);
allowed = 0;
goto out; goto out;
} }
allowed = 1; allowed = 1;