Eric Biggers 054be9aed8 crypto: af_alg - avoid undefined behavior accessing salg_name ... commit 92eb6c3060 upstream. Commit 3f69cc6076 ("crypto: af_alg - Allow arbitrarily long algorithm names") made the kernel start accepting arbitrarily long algorithm names in sockaddr_alg. However, the actual length of the salg_name field stayed at the original 64 bytes. This is broken because the kernel can access indices >= 64 in salg_name, which is undefined behavior -- even though the memory that is accessed is still located within the sockaddr structure. It would only be defined behavior if the array were properly marked as arbitrary-length (either by making it a flexible array, which is the recommended way these days, or by making it an array of length 0 or 1). We can't simply change salg_name into a flexible array, since that would break source compatibility with userspace programs that embed sockaddr_alg into another struct, or (more commonly) declare a sockaddr_alg like 'struct sockaddr_alg sa = { .salg_name = "foo" };'. One solution would be to change salg_name into a flexible array only when '#ifdef __KERNEL__'. However, that would keep userspace without an easy way to actually use the longer algorithm names. Instead, add a new structure 'sockaddr_alg_new' that has the flexible array field, and expose it to both userspace and the kernel. Make the kernel use it correctly in alg_bind(). This addresses the syzbot report "UBSAN: array-index-out-of-bounds in alg_bind" (https://syzkaller.appspot.com/bug?extid=92ead4eb8e26a26d465e). Reported-by: syzbot+92ead4eb8e26a26d465e@syzkaller.appspotmail.com Fixes: 3f69cc6076 ("crypto: af_alg - Allow arbitrarily long algorithm names") Cc: <stable@vger.kernel.org> # v4.12+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-12-30 11:51:00 +01:00
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asm-generic	mm: introduce MADV_PAGEOUT	2019-09-25 17:51:41 -07:00
drm	drm/amdgpu: return tcc_disabled_mask to userspace	2019-10-02 12:58:33 -05:00
linux	crypto: af_alg - avoid undefined behavior accessing salg_name	2020-12-30 11:51:00 +01:00
misc	habanalabs: stop using the acronym KMD	2019-09-05 14:55:27 +03:00
mtd	mtd: abi: do not use C++ style comments in uapi header	2019-07-07 20:31:29 +02:00
rdma	rdma: Remove nes ABI header	2020-01-17 19:48:39 +01:00
scsi	scsi: use __u{8,16,32,64} instead of uint{8,16,32,64}_t in uapi headers	2019-08-12 22:19:27 -04:00
sound	ASoC: Intel: Skylake: Automatic DMIC format configuration according to information from NHLT	2020-12-02 08:49:57 +01:00
video	…
xen	…
Kbuild	kbuild: re-implement Makefile.headersinst without recursion	2019-06-15 19:57:02 +09:00