From: Andrew Morton <akpm@linux-foundation.org>
To: akpm@linux-foundation.org, linux-mm@kvack.org,
mm-commits@vger.kernel.org, sj@kernel.org,
stable@vger.kernel.org, torvalds@linux-foundation.org
Subject: [patch 13/15] mm/damon/dbgfs: fix missed use of damon_dbgfs_lock
Date: Fri, 19 Nov 2021 16:43:52 -0800 [thread overview]
Message-ID: <20211120004352.cP--sDA9q%akpm@linux-foundation.org> (raw)
In-Reply-To: <20211119164248.50feee07c5d2cc6cc4addf97@linux-foundation.org>
From: SeongJae Park <sj@kernel.org>
Subject: mm/damon/dbgfs: fix missed use of damon_dbgfs_lock
DAMON debugfs is supposed to protect dbgfs_ctxs, dbgfs_nr_ctxs, and
dbgfs_dirs using damon_dbgfs_lock. However, some of the code is accessing
the variables without the protection. This commit fixes it by protecting
all such accesses.
Link: https://lkml.kernel.org/r/20211110145758.16558-3-sj@kernel.org
Fixes: 75c1c2b53c78 ("mm/damon/dbgfs: support multiple contexts")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/damon/dbgfs.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
--- a/mm/damon/dbgfs.c~mm-damon-dbgfs-fix-missed-use-of-damon_dbgfs_lock
+++ a/mm/damon/dbgfs.c
@@ -877,12 +877,14 @@ static ssize_t dbgfs_monitor_on_write(st
return -EINVAL;
}
+ mutex_lock(&damon_dbgfs_lock);
if (!strncmp(kbuf, "on", count)) {
int i;
for (i = 0; i < dbgfs_nr_ctxs; i++) {
if (damon_targets_empty(dbgfs_ctxs[i])) {
kfree(kbuf);
+ mutex_unlock(&damon_dbgfs_lock);
return -EINVAL;
}
}
@@ -892,6 +894,7 @@ static ssize_t dbgfs_monitor_on_write(st
} else {
ret = -EINVAL;
}
+ mutex_unlock(&damon_dbgfs_lock);
if (!ret)
ret = count;
@@ -944,15 +947,16 @@ static int __init __damon_dbgfs_init(voi
static int __init damon_dbgfs_init(void)
{
- int rc;
+ int rc = -ENOMEM;
+ mutex_lock(&damon_dbgfs_lock);
dbgfs_ctxs = kmalloc(sizeof(*dbgfs_ctxs), GFP_KERNEL);
if (!dbgfs_ctxs)
- return -ENOMEM;
+ goto out;
dbgfs_ctxs[0] = dbgfs_new_ctx();
if (!dbgfs_ctxs[0]) {
kfree(dbgfs_ctxs);
- return -ENOMEM;
+ goto out;
}
dbgfs_nr_ctxs = 1;
@@ -963,6 +967,8 @@ static int __init damon_dbgfs_init(void)
pr_err("%s: dbgfs init failed\n", __func__);
}
+out:
+ mutex_unlock(&damon_dbgfs_lock);
return rc;
}
_
next prev parent reply other threads:[~2021-11-20 0:43 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-20 0:42 incoming Andrew Morton
2021-11-20 0:43 ` [patch 01/15] mm/swap.c:put_pages_list(): reinitialise the page list Andrew Morton
2021-11-20 0:43 ` [patch 02/15] ipc: WARN if trying to remove ipc object which is absent Andrew Morton
2021-11-20 0:43 ` [patch 03/15] shm: extend forced shm destroy to support objects from several IPC nses Andrew Morton
2021-11-20 0:43 ` [patch 04/15] mm: emit the "free" trace report before freeing memory in kmem_cache_free() Andrew Morton
2021-11-20 0:43 ` [patch 05/15] hexagon: export raw I/O routines for modules Andrew Morton
2021-11-20 0:43 ` [patch 06/15] hexagon: clean up timer-regs.h Andrew Morton
2021-11-20 0:43 ` [patch 07/15] hexagon: ignore vmlinux.lds Andrew Morton
2021-11-20 0:43 ` [patch 08/15] mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag Andrew Morton
2021-11-20 0:43 ` [patch 09/15] hugetlb: fix hugetlb cgroup refcounting during mremap Andrew Morton
2021-11-20 0:43 ` [patch 10/15] hugetlb, userfaultfd: fix reservation restore on userfaultfd error Andrew Morton
2021-11-20 0:43 ` [patch 11/15] kasan: test: silence intentional read overflow warnings Andrew Morton
2021-11-20 0:43 ` [patch 12/15] mm/damon/dbgfs: use '__GFP_NOWARN' for user-specified size buffer allocation Andrew Morton
2021-11-20 0:43 ` Andrew Morton [this message]
2021-11-20 0:43 ` [patch 14/15] kmap_local: don't assume kmap PTEs are linear arrays in memory Andrew Morton
2021-11-20 0:43 ` [patch 15/15] proc/vmcore: fix clearing user buffer by properly using clear_user() Andrew Morton
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