[patch 127/227] mm/mlock: fix potential imbalanced rlimit ucounts adjustment

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm/mlock: fix potential imbalanced rlimit ucounts adjustment

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@xxxxxxxxxx
Fixes: d7c9e99aee48 ("Reimplement RLIMIT_MEMLOCK on top of ucounts")
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Herbert van den Bergh <herbert.van.den.bergh@xxxxxxxxxx>
Cc: Chris Mason <chris.mason@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 mm/mlock.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/mlock.c~mm-mlock-fix-potential-imbalanced-rlimit-ucounts-adjustment
+++ a/mm/mlock.c
@@ -839,6 +839,7 @@ int user_shm_lock(size_t size, struct uc
 	}
 	if (!get_ucounts(ucounts)) {
 		dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked);
+		allowed = 0;
 		goto out;
 	}
 	allowed = 1;
_



[Index of Archives]     [Kernel Archive]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]

  Powered by Linux