From 0acf07d240a84069c4a6651e6030cf35d30c7159 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 16 Apr 2014 10:54:34 -0700 Subject: [PATCH] seccomp: fix memory leak on filter attach This sets the correct error code when final filter memory is unavailable, and frees the raw filter no matter what. unreferenced object 0xffff8800d6ea4000 (size 512): comm "sshd", pid 278, jiffies 4294898315 (age 46.653s) hex dump (first 32 bytes): 21 00 00 00 04 00 00 00 15 00 01 00 3e 00 00 c0 !...........>... 06 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!....... backtrace: [] kmemleak_alloc+0x4e/0xb0 [] __kmalloc+0x280/0x320 [] prctl_set_seccomp+0x11e/0x3b0 [] SyS_prctl+0x3bb/0x4a0 [] system_call_fastpath+0x1a/0x1f [] 0xffffffffffffffff Reported-by: Masami Ichikawa Signed-off-by: Kees Cook Tested-by: Masami Ichikawa Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- kernel/seccomp.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 590c37925084..b35c21503a36 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -255,6 +255,7 @@ static long seccomp_attach_filter(struct sock_fprog *fprog) goto free_prog; /* Allocate a new seccomp_filter */ + ret = -ENOMEM; filter = kzalloc(sizeof(struct seccomp_filter) + sizeof(struct sock_filter_int) * new_len, GFP_KERNEL|__GFP_NOWARN); @@ -264,6 +265,7 @@ static long seccomp_attach_filter(struct sock_fprog *fprog) ret = sk_convert_filter(fp, fprog->len, filter->insnsi, &new_len); if (ret) goto free_filter; + kfree(fp); atomic_set(&filter->usage, 1); filter->len = new_len;