From 3096ba94fa87b22664baa91e71a55ce698bb8aed Mon Sep 17 00:00:00 2001 From: YueHaibing Date: Tue, 19 Feb 2019 10:10:38 +0800 Subject: [PATCH 3/3] exec: Fix mem leak in kernel_read_file syzkaller report this: BUG: memory leak unreferenced object 0xffffc9000488d000 (size 9195520): comm "syz-executor.0", pid 2752, jiffies 4294787496 (age 18.757s) hex dump (first 32 bytes): ff ff ff ff ff ff ff ff a8 00 00 00 01 00 00 00 ................ 02 00 00 00 00 00 00 00 80 a1 7a c1 ff ff ff ff ..........z..... backtrace: [<000000000863775c>] __vmalloc_node mm/vmalloc.c:1795 [inline] [<000000000863775c>] __vmalloc_node_flags mm/vmalloc.c:1809 [inline] [<000000000863775c>] vmalloc+0x8c/0xb0 mm/vmalloc.c:1831 [<000000003f668111>] kernel_read_file+0x58f/0x7d0 fs/exec.c:924 [<000000002385813f>] kernel_read_file_from_fd+0x49/0x80 fs/exec.c:993 [<0000000011953ff1>] __do_sys_finit_module+0x13b/0x2a0 kernel/module.c:3895 [<000000006f58491f>] do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290 [<00000000ee78baf4>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<00000000241f889b>] 0xffffffffffffffff It should goto 'out_free' lable to free allocated buf while kernel_read fails. Fixes: 39d637af5aa7 ("vfs: forbid write access when reading a file into memory") Signed-off-by: YueHaibing Signed-off-by: Al Viro --- fs/exec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/exec.c b/fs/exec.c index fc281b738a98..20c33029a062 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -929,7 +929,7 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, bytes = kernel_read(file, *buf + pos, i_size - pos, &pos); if (bytes < 0) { ret = bytes; - goto out; + goto out_free; } if (bytes == 0) -- 2.20.1