user/sven/linux.git/include/linux, branch v4.19.178

net: icmp: pass zeroed opts from icmp{,v6}_ndo_send before sending

2021-03-04T08:39:59Z

commit ee576c47db60432c37e54b1e2b43a8ca6d3a8dca upstream. The icmp{,v6}_send functions make all sorts of use of skb->cb, casting it with IPCB or IP6CB, assuming the skb to have come directly from the inet layer. But when the packet comes from the ndo layer, especially when forwarded, there's no telling what might be in skb->cb at that point. As a result, the icmp sending code risks reading bogus memory contents, which can result in nasty stack overflows such as this one reported by a user: panic+0x108/0x2ea __stack_chk_fail+0x14/0x20 __icmp_send+0x5bd/0x5c0 icmp_ndo_send+0x148/0x160 In icmp_send, skb->cb is cast with IPCB and an ip_options struct is read from it. The optlen parameter there is of particular note, as it can induce writes beyond bounds. There are quite a few ways that can happen in __ip_options_echo. For example: // sptr/skb are attacker-controlled skb bytes sptr = skb_network_header(skb); // dptr/dopt points to stack memory allocated by __icmp_send dptr = dopt->__data; // sopt is the corrupt skb->cb in question if (sopt->rr) { optlen = sptr[sopt->rr+1]; // corrupt skb->cb + skb->data soffset = sptr[sopt->rr+2]; // corrupt skb->cb + skb->data // this now writes potentially attacker-controlled data, over // flowing the stack: memcpy(dptr, sptr+sopt->rr, optlen); } In the icmpv6_send case, the story is similar, but not as dire, as only IP6CB(skb)->iif and IP6CB(skb)->dsthao are used. The dsthao case is worse than the iif case, but it is passed to ipv6_find_tlv, which does a bit of bounds checking on the value. This is easy to simulate by doing a `memset(skb->cb, 0x41, sizeof(skb->cb));` before calling icmp{,v6}_ndo_send, and it's only by good fortune and the rarity of icmp sending from that context that we've avoided reports like this until now. For example, in KASAN: BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0xa0e/0x12b0 Write of size 38 at addr ffff888006f1f80e by task ping/89 CPU: 2 PID: 89 Comm: ping Not tainted 5.10.0-rc7-debug+ #5 Call Trace: dump_stack+0x9a/0xcc print_address_description.constprop.0+0x1a/0x160 __kasan_report.cold+0x20/0x38 kasan_report+0x32/0x40 check_memory_region+0x145/0x1a0 memcpy+0x39/0x60 __ip_options_echo+0xa0e/0x12b0 __icmp_send+0x744/0x1700 Actually, out of the 4 drivers that do this, only gtp zeroed the cb for the v4 case, while the rest did not. So this commit actually removes the gtp-specific zeroing, while putting the code where it belongs in the shared infrastructure of icmp{,v6}_ndo_send. This commit fixes the issue by passing an empty IPCB or IP6CB along to the functions that actually do the work. For the icmp_send, this was already trivial, thanks to __icmp_send providing the plumbing function. For icmpv6_send, this required a tiny bit of refactoring to make it behave like the v4 case, after which it was straight forward. Fixes: a2b78e9b2cac ("sunvnet: generate ICMP PTMUD messages for smaller port MTUs") Reported-by: SinYu Reviewed-by: Willem de Bruijn Link: https://lore.kernel.org/netdev/CAF=yD-LOF116aHub6RMe8vB8ZpnrrnoTdqhobEx+bvoA8AsP0w@mail.gmail.com/T/ Signed-off-by: Jason A. Donenfeld Link: https://lore.kernel.org/r/20210223131858.72082-1-Jason@zx2c4.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ipv6: silence compilation warning for non-IPV6 builds

2021-03-04T08:39:59Z

commit 1faba27f11c8da244e793546a1b35a9b1da8208e upstream. The W=1 compilation of allmodconfig generates the following warning: net/ipv6/icmp.c:448:6: warning: no previous prototype for 'icmp6_send' [-Wmissing-prototypes] 448 | void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info, | ^~~~~~~~~~ Fix it by providing function declaration for builds with ipv6 as a module. Signed-off-by: Leon Romanovsky Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ipv6: icmp6: avoid indirect call for icmpv6_send()

2021-03-04T08:39:59Z

commit cc7a21b6fbd945f8d8f61422ccd27203c1fafeb7 upstream. If IPv6 is builtin, we do not need an expensive indirect call to reach icmp6_send(). v2: put inline keyword before the type to avoid sparse warnings. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

icmp: allow icmpv6_ndo_send to work with CONFIG_IPV6=n

2021-03-04T08:39:58Z

commit a8e41f6033a0c5633d55d6e35993c9e2005d872f upstream. The icmpv6_send function has long had a static inline implementation with an empty body for CONFIG_IPV6=n, so that code calling it doesn't need to be ifdef'd. The new icmpv6_ndo_send function, which is intended for drivers as a drop-in replacement with an identical function signature, should follow the same pattern. Without this patch, drivers that used to work with CONFIG_IPV6=n now result in a linker error. Cc: Chen Zhou Reported-by: Hulk Robot Fixes: 0b41713b6066 ("icmp: introduce helper for nat'd source address in network device context") Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

icmp: introduce helper for nat'd source address in network device context

2021-03-04T08:39:58Z

commit 0b41713b606694257b90d61ba7e2712d8457648b upstream. This introduces a helper function to be called only by network drivers that wraps calls to icmp[v6]_send in a conntrack transformation, in case NAT has been used. We don't want to pollute the non-driver path, though, so we introduce this as a helper to be called by places that actually make use of this, as suggested by Florian. Signed-off-by: Jason A. Donenfeld Cc: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

dm: fix deadlock when swapping to encrypted device

2021-03-04T08:39:57Z

commit a666e5c05e7c4aaabb2c5d58117b0946803d03d2 upstream. The system would deadlock when swapping to a dm-crypt device. The reason is that for each incoming write bio, dm-crypt allocates memory that holds encrypted data. These excessive allocations exhaust all the memory and the result is either deadlock or OOM trigger. This patch limits the number of in-flight swap bios, so that the memory consumed by dm-crypt is limited. The limit is enforced if the target set the "limit_swap_bios" variable and if the bio has REQ_SWAP set. Non-swap bios are not affected becuase taking the semaphore would cause performance degradation. This is similar to request-based drivers - they will also block when the number of requests is over the limit. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

mm/rmap: fix potential pte_unmap on an not mapped pte

2021-03-04T08:39:50Z

[ Upstream commit 5d5d19eda6b0ee790af89c45e3f678345be6f50f ] For PMD-mapped page (usually THP), pvmw->pte is NULL. For PTE-mapped THP, pvmw->pte is mapped. But for HugeTLB pages, pvmw->pte is not mapped and set to the relevant page table entry. So in page_vma_mapped_walk_done(), we may do pte_unmap() for HugeTLB pte which is not mapped. Fix this by checking pvmw->page against PageHuge before trying to do pte_unmap(). Link: https://lkml.kernel.org/r/20210127093349.39081-1-linmiaohe@huawei.com Fixes: ace71a19cec5 ("mm: introduce page_vma_mapped_walk()") Signed-off-by: Hongxiang Lou Signed-off-by: Miaohe Lin Tested-by: Sedat Dilek Cc: Kees Cook Cc: Nathan Chancellor Cc: Mike Kravetz Cc: Shakeel Butt Cc: Johannes Weiner Cc: Vlastimil Babka Cc: Michel Lespinasse Cc: Nick Desaulniers Cc: "Kirill A. Shutemov" Cc: Wei Yang Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Brian Geffon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

certs: Fix blacklist flag type confusion

2021-03-04T08:39:44Z

[ Upstream commit 4993e1f9479a4161fd7d93e2b8b30b438f00cb0f ] KEY_FLAG_KEEP is not meant to be passed to keyring_alloc() or key_alloc(), as these only take KEY_ALLOC_* flags. KEY_FLAG_KEEP has the same value as KEY_ALLOC_BYPASS_RESTRICTION, but fortunately only key_create_or_update() uses it. LSMs using the key_alloc hook don't check that flag. KEY_FLAG_KEEP is then ignored but fortunately (again) the root user cannot write to the blacklist keyring, so it is not possible to remove a key/hash from it. Fix this by adding a KEY_ALLOC_SET_KEEP flag that tells key_alloc() to set KEY_FLAG_KEEP on the new key. blacklist_init() can then, correctly, pass this to keyring_alloc(). We can also use this in ima_mok_init() rather than setting the flag manually. Note that this doesn't fix an observable bug with the current implementation but it is required to allow addition of new hashes to the blacklist in the future without making it possible for them to be removed. Fixes: 734114f8782f ("KEYS: Add a system blacklist keyring") Reported-by: Mickaël Salaün Signed-off-by: David Howells cc: Mickaël Salaün cc: Mimi Zohar Cc: David Woodhouse Signed-off-by: Sasha Levin

ima: Free IMA measurement buffer after kexec syscall

2021-03-04T08:39:42Z

[ Upstream commit f31e3386a4e92ba6eda7328cb508462956c94c64 ] IMA allocates kernel virtual memory to carry forward the measurement list, from the current kernel to the next kernel on kexec system call, in ima_add_kexec_buffer() function. This buffer is not freed before completing the kexec system call resulting in memory leak. Add ima_buffer field in "struct kimage" to store the virtual address of the buffer allocated for the IMA measurement list. Free the memory allocated for the IMA measurement list in kimage_file_post_load_cleanup() function. Signed-off-by: Lakshmi Ramasubramanian Suggested-by: Tyler Hicks Reviewed-by: Thiago Jung Bauermann Reviewed-by: Tyler Hicks Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list") Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

bpf: Avoid warning when re-casting __bpf_call_base into __bpf_call_base_args

2021-03-04T08:39:33Z

[ Upstream commit 6943c2b05bf09fd5c5729f7d7d803bf3f126cb9a ] BPF interpreter uses extra input argument, so re-casts __bpf_call_base into __bpf_call_base_args. Avoid compiler warning about incompatible function prototypes by casting to void * first. Fixes: 1ea47e01ad6e ("bpf: add support for bpf_call to interpreter") Reported-by: kernel test robot Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20210112075520.4103414-3-andrii@kernel.org Signed-off-by: Sasha Levin