We do not ever intend to unregister "user" sysctl table, unfortunately it leads kmemleak to believe that we are leaking memory:
unreferenced object 0xffff8807383bfd48 (size 96): comm "swapper/0", pid 1, jiffies 4294894636 (age 278.320s) hex dump (first 32 bytes): a0 b4 b0 ba ff ff ff ff 00 00 00 00 01 00 00 00 ................ 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffffb7de59e8>] kmemleak_alloc+0x28/0x50 [<ffffffffb676e2f6>] __kmalloc+0x206/0x5a0 [<ffffffffb69be2d3>] __register_sysctl_table+0xb3/0x1130 [<ffffffffb69bf36b>] register_sysctl+0x1b/0x20 [<ffffffffba840de1>] user_namespace_sysctl_init+0x17/0x4c [<ffffffffb60022b7>] do_one_initcall+0xb7/0x2a0 [<ffffffffba7eb102>] kernel_init_freeable+0x597/0x636 [<ffffffffb7de0433>] kernel_init+0x13/0x140 [<ffffffffb7dfb36a>] ret_from_fork+0x2a/0x40t show [<ffffffffffffffff>] 0xffffffffffffffff Let's annotate the pointer as kmemleak_not_leak() to suppress the kmemleak false positive. Reported-by: Jakub Kicinski <kubak...@wp.pl> Signed-off-by: Dmitry Torokhov <dmitry.torok...@gmail.com> --- This was only compiled; Jakub, could you give it a spin? kernel/ucount.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/ucount.c b/kernel/ucount.c index 9d20d5d..07d69b2 100644 --- a/kernel/ucount.c +++ b/kernel/ucount.c @@ -5,6 +5,7 @@ * License. */ +#include <linux/kmemleak.h> #include <linux/stat.h> #include <linux/sysctl.h> #include <linux/slab.h> @@ -226,6 +227,7 @@ static __init int user_namespace_sysctl_init(void) */ user_header = register_sysctl("user", empty); BUG_ON(!user_header); + kmemleak_not_leak(user_header); BUG_ON(!setup_userns_sysctls(&init_user_ns)); #endif return 0; -- 2.8.0.rc3.226.g39d4020 -- Dmitry