• Andrey Ryabinin's avatar
    X.509: Fix double free in x509_cert_parse() [ver #3] · 2b95fda2
    Andrey Ryabinin authored
    We shouldn't free cert->pub->key in x509_cert_parse() because
    x509_free_certificate() also does this:
    	BUG: Double free or freeing an invalid pointer
    	...
    	Call Trace:
    	 [<ffffffff81896c20>] dump_stack+0x63/0x83
    	 [<ffffffff81356571>] kasan_object_err+0x21/0x70
    	 [<ffffffff81356ed9>] kasan_report_double_free+0x49/0x60
    	 [<ffffffff813561ad>] kasan_slab_free+0x9d/0xc0
    	 [<ffffffff81350b7a>] kfree+0x8a/0x1a0
    	 [<ffffffff81844fbf>] public_key_free+0x1f/0x30
    	 [<ffffffff818455d4>] x509_free_certificate+0x24/0x90
    	 [<ffffffff818460bc>] x509_cert_parse+0x2bc/0x300
    	 [<ffffffff81846cae>] x509_key_preparse+0x3e/0x330
    	 [<ffffffff818444cf>] asymmetric_key_preparse+0x6f/0x100
    	 [<ffffffff8178bec0>] key_create_or_update+0x260/0x5f0
    	 [<ffffffff8178e6d9>] SyS_add_key+0x199/0x2a0
    	 [<ffffffff821d823b>] entry_SYSCALL_64_fastpath+0x1e/0xad
    	Object at ffff880110bd1900, in cache kmalloc-512 size: 512
    	....
    	Freed:
    	PID = 2579
    	[<ffffffff8104283b>] save_stack_trace+0x1b/0x20
    	[<ffffffff813558f6>] save_stack+0x46/0xd0
    	[<ffffffff81356183>] kasan_slab_free+0x73/0xc0
    	[<ffffffff81350b7a>] kfree+0x8a/0x1a0
    	[<ffffffff818460a3>] x509_cert_parse+0x2a3/0x300
    	[<ffffffff81846cae>] x509_key_preparse+0x3e/0x330
    	[<ffffffff818444cf>] asymmetric_key_preparse+0x6f/0x100
    	[<ffffffff8178bec0>] key_create_or_update+0x260/0x5f0
    	[<ffffffff8178e6d9>] SyS_add_key+0x199/0x2a0
    	[<ffffffff821d823b>] entry_SYSCALL_64_fastpath+0x1e/0xad
    
    Fixes: db6c43bd ("crypto: KEYS: convert public key and digsig asym to the akcipher api")
    Signed-off-by: default avatarAndrey Ryabinin <aryabinin@virtuozzo.com>
    Cc: <stable@vger.kernel.org>
    Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
    Signed-off-by: default avatarJames Morris <james.l.morris@oracle.com>
    2b95fda2
x509_cert_parser.c 15.8 KB