unimore/kernel-hacking-2024-linux-steffo
unimore/kernel-hacking-2024-linux-steffo
1
Fork 0
Code Pull requests 5 Wiki Activity

ucounts: Pair inc_rlimit_ucounts with dec_rlimit_ucoutns in commit_creds

Browse source 
The purpose of inc_rlimit_ucounts and dec_rlimit_ucounts in commit_creds
is to change which rlimit counter is used to track a process when the
credentials changes.

Use the same test for both to guarantee the tracking is correct.

Cc: stable@vger.kernel.org
Fixes: 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
Link: https://lkml.kernel.org/r/87v91us0w4.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2021-10-16 12:30:00 -05:00
parent 15bc01effe
commit 629715adc6
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
kernel/cred.c
View file

@ -501,7 +501,7 @@ int commit_creds(struct cred *new)
inc_rlimit_ucounts(new->ucounts, UCOUNT_RLIMIT_NPROC, 1);
rcu_assign_pointer(task->real_cred, new);
rcu_assign_pointer(task->cred, new);
if (new->user != old->user)
if (new->user != old->user || new->user_ns != old->user_ns)
dec_rlimit_ucounts(old->ucounts, UCOUNT_RLIMIT_NPROC, 1);
alter_cred_subscribers(old, -2);