From: SeongJae Park sj@kernel.org
stable inclusion from stable-v6.6.3 commit 33edac1f26a4ae186aa4236608d4c20f7b19176d category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8LBQP
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit b4936b544b08ed44949055b92bd25f77759ebafc upstream.
Patch series "mm/damon/sysfs: fix unhandled return values".
Some of DAMON sysfs interface code is not handling return values from some functions. As a result, confusing user input handling or NULL-dereference is possible. Check those properly.
This patch (of 3):
damon_sysfs_update_target() returns error code for failures, but its caller, damon_sysfs_set_targets() is ignoring that. The update function seems making no critical change in case of such failures, but the behavior will look like DAMON sysfs is silently ignoring or only partially accepting the user input. Fix it.
Link: https://lkml.kernel.org/r/20231106233408.51159-1-sj@kernel.org Link: https://lkml.kernel.org/r/20231106233408.51159-2-sj@kernel.org Fixes: 19467a950b49 ("mm/damon/sysfs: remove requested targets when online-commit inputs") Signed-off-by: SeongJae Park sj@kernel.org Cc: stable@vger.kernel.org [5.19+] Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- mm/damon/sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 7e040286cf01..faaef5098e26 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -1203,8 +1203,10 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx,
damon_for_each_target_safe(t, next, ctx) { if (i < sysfs_targets->nr) { - damon_sysfs_update_target(t, ctx, + err = damon_sysfs_update_target(t, ctx, sysfs_targets->targets_arr[i]); + if (err) + return err; } else { if (damon_target_has_pid(ctx)) put_pid(t->pid);