From: Miaohe Lin <linmiaohe@xxxxxxxxxx> Subject: mm/swapfile.c: fix potential memory leak in sys_swapon If we failed to drain inode, we would forget to free the swap address space allocated by init_swap_address_space() above. Link: https://lkml.kernel.org/r/20200930101803.53884-1-linmiaohe@xxxxxxxxxx Fixes: dc617f29dbe5 ("vfs: don't allow writes to swap files") Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/swapfile.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/mm/swapfile.c~mm-fix-potential-memory-leak-in-sys_swapon +++ a/mm/swapfile.c @@ -3342,7 +3342,7 @@ SYSCALL_DEFINE2(swapon, const char __use error = inode_drain_writes(inode); if (error) { inode->i_flags &= ~S_SWAPFILE; - goto bad_swap_unlock_inode; + goto free_swap_address_space; } mutex_lock(&swapon_mutex); @@ -3367,6 +3367,8 @@ SYSCALL_DEFINE2(swapon, const char __use error = 0; goto out; +free_swap_address_space: + exit_swap_address_space(p->type); bad_swap_unlock_inode: inode_unlock(inode); bad_swap: _
