Eric Biggers 709b2d03bb crypto: af_alg - avoid undefined behavior accessing salg_name ... commit 92eb6c3060ebe3adf381fd9899451c5b047bb14d 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>		2020-12-26 16:02:45 +01:00
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asm-generic	mm/madvise: introduce process_madvise() syscall: an external memory hinting API	2020-10-18 09:27:10 -07:00
drm
linux	crypto: af_alg - avoid undefined behavior accessing salg_name	2020-12-26 16:02:45 +01:00
misc
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rdma
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sound	ALSA: fix kernel-doc markups	2020-10-26 15:26:31 +01:00
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