From 3494ec4c7f2f6f0261cbf582ea6a605f9033cb7b Mon Sep 17 00:00:00 2001 From: Debarshi Dutta Date: Tue, 8 Aug 2017 15:34:57 +0530 Subject: Revert "gpu: nvgpu: Remove IOCTL FREE_OBJ_CTX" Bug 200336148 This reverts commit 2db040946ff8340485b2b33fe5a46f3166fa96f6. Change-Id: I8a80a7bd1bd8b1a949fba26b683ac1c9bebc0c04 Signed-off-by: Debarshi Dutta Reviewed-on: https://git-master.nvidia.com/r/1534941 GVS: Gerrit_Virtual_Submit Reviewed-by: Bibek Basu --- include/linux/nvhost_ioctl.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/nvhost_ioctl.h b/include/linux/nvhost_ioctl.h index a1011e5a1daf..b060864ff1d1 100644 --- a/include/linux/nvhost_ioctl.h +++ b/include/linux/nvhost_ioctl.h @@ -3,7 +3,7 @@ * * Tegra graphics host driver * - * Copyright (c) 2009-2017, NVIDIA Corporation. All rights reserved. + * Copyright (c) 2009-2014, NVIDIA Corporation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -118,6 +118,10 @@ struct nvhost_alloc_obj_ctx_args { __u64 obj_id; /* output, used to free later */ }; +struct nvhost_free_obj_ctx_args { + __u64 obj_id; /* obj ctx to free */ +}; + struct nvhost_alloc_gpfifo_args { __u32 num_entries; #define NVHOST_ALLOC_GPFIFO_FLAGS_VPR_ENABLED (1 << 0) /* set owner channel of this gpfifo as a vpr channel */ @@ -386,6 +390,8 @@ struct nvhost_set_ctxswitch_args { _IOWR(NVHOST_IOCTL_MAGIC, 107, struct nvhost_submit_gpfifo_args) #define NVHOST_IOCTL_CHANNEL_ALLOC_OBJ_CTX \ _IOWR(NVHOST_IOCTL_MAGIC, 108, struct nvhost_alloc_obj_ctx_args) +#define NVHOST_IOCTL_CHANNEL_FREE_OBJ_CTX \ + _IOR(NVHOST_IOCTL_MAGIC, 109, struct nvhost_free_obj_ctx_args) #define NVHOST_IOCTL_CHANNEL_ZCULL_BIND \ _IOWR(NVHOST_IOCTL_MAGIC, 110, struct nvhost_zcull_bind_args) #define NVHOST_IOCTL_CHANNEL_SET_ERROR_NOTIFIER \ -- cgit v1.2.3 From bc078fb62c6d3c80bcba2c63cb57ad06e8b419e4 Mon Sep 17 00:00:00 2001 From: Sri Krishna chowdary Date: Fri, 23 Jun 2017 11:56:03 +0530 Subject: mm: larger stack guard gap, between vmas commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream. Stack guard page is a useful feature to reduce a risk of stack smashing into a different mapping. We have been using a single page gap which is sufficient to prevent having stack adjacent to a different mapping. But this seems to be insufficient in the light of the stack usage in userspace. E.g. glibc uses as large as 64kB alloca() in many commonly used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX] which is 256kB or stack strings with MAX_ARG_STRLEN. This will become especially dangerous for suid binaries and the default no limit for the stack size limit because those applications can be tricked to consume a large portion of the stack and a single glibc call could jump over the guard page. These attacks are not theoretical, unfortunatelly. Make those attacks less probable by increasing the stack guard gap to 1MB (on systems with 4k pages; but make it depend on the page size because systems with larger base pages might cap stack allocations in the PAGE_SIZE units) which should cover larger alloca() and VLA stack allocations. It is obviously not a full fix because the problem is somehow inherent, but it should reduce attack space a lot. One could argue that the gap size should be configurable from userspace, but that can be done later when somebody finds that the new 1MB is wrong for some special case applications. For now, add a kernel command line option (stack_guard_gap) to specify the stack gap size (in page units). Implementation wise, first delete all the old code for stack guard page: because although we could get away with accounting one extra page in a stack vma, accounting a larger gap can break userspace - case in point, a program run with "ulimit -S -v 20000" failed when the 1MB gap was counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK and strict non-overcommit mode. Instead of keeping gap inside the stack vma, maintain the stack guard gap as a gap between vmas: using vm_start_gap() in place of vm_start (or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few places which need to respect the gap - mainly arch_get_unmapped_area(), and and the vma tree's subtree_gap support for that. Bug 1946430 Change-Id: I9a66aabc34b687996fb971e01bb0ef30a3d4de7d Original-patch-by: Oleg Nesterov Original-patch-by: Michal Hocko Signed-off-by: Hugh Dickins Acked-by: Michal Hocko Tested-by: Helge Deller # parisc Signed-off-by: Linus Torvalds [wt: backport to 4.11: adjust context] [wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide] [wt: backport to 4.4: adjust context ; drop ppc hugetlb_radix changes] Signed-off-by: Willy Tarreau Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sri Krishna chowdary Reviewed-on: https://git-master.nvidia.com/r/1509390 GVS: Gerrit_Virtual_Submit Tested-by: Bibek Basu Reviewed-by: Bibek Basu --- include/linux/mm.h | 53 +++++++++++++++++++++++++---------------------------- 1 file changed, 25 insertions(+), 28 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 03a60a38ec45..9d572d445e3e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1066,34 +1066,6 @@ int set_page_dirty(struct page *page); int set_page_dirty_lock(struct page *page); int clear_page_dirty_for_io(struct page *page); -/* Is the vma a continuation of the stack vma above it? */ -static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr) -{ - return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN); -} - -static inline int stack_guard_page_start(struct vm_area_struct *vma, - unsigned long addr) -{ - return (vma->vm_flags & VM_GROWSDOWN) && - (vma->vm_start == addr) && - !vma_growsdown(vma->vm_prev, addr); -} - -/* Is the vma a continuation of the stack vma below it? */ -static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr) -{ - return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP); -} - -static inline int stack_guard_page_end(struct vm_area_struct *vma, - unsigned long addr) -{ - return (vma->vm_flags & VM_GROWSUP) && - (vma->vm_end == addr) && - !vma_growsup(vma->vm_next, addr); -} - extern pid_t vm_is_stack(struct task_struct *task, struct vm_area_struct *vma, int in_group); @@ -1620,6 +1592,7 @@ unsigned long ra_submit(struct file_ra_state *ra, struct address_space *mapping, struct file *filp); +extern unsigned long stack_guard_gap; /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ extern int expand_stack(struct vm_area_struct *vma, unsigned long address); @@ -1648,6 +1621,30 @@ static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * m return vma; } +static inline unsigned long vm_start_gap(struct vm_area_struct *vma) +{ + unsigned long vm_start = vma->vm_start; + + if (vma->vm_flags & VM_GROWSDOWN) { + vm_start -= stack_guard_gap; + if (vm_start > vma->vm_start) + vm_start = 0; + } + return vm_start; +} + +static inline unsigned long vm_end_gap(struct vm_area_struct *vma) +{ + unsigned long vm_end = vma->vm_end; + + if (vma->vm_flags & VM_GROWSUP) { + vm_end += stack_guard_gap; + if (vm_end < vma->vm_end) + vm_end = -PAGE_SIZE; + } + return vm_end; +} + static inline unsigned long vma_pages(struct vm_area_struct *vma) { return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; -- cgit v1.2.3 From ab6caaa6ab10ff7e3c6d536277dacf1e644c3cd2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 17 Aug 2016 05:56:26 -0700 Subject: tcp: fix use after free in tcp_xmit_retransmit_queue() When tcp_sendmsg() allocates a fresh and empty skb, it puts it at the tail of the write queue using tcp_add_write_queue_tail() Then it attempts to copy user data into this fresh skb. If the copy fails, we undo the work and remove the fresh skb. Unfortunately, this undo lacks the change done to tp->highest_sack and we can leave a dangling pointer (to a freed skb) Later, tcp_xmit_retransmit_queue() can dereference this pointer and access freed memory. For regular kernels where memory is not unmapped, this might cause SACK bugs because tcp_highest_sack_seq() is buggy, returning garbage instead of tp->snd_nxt, but with various debug features like CONFIG_DEBUG_PAGEALLOC, this can crash the kernel. This bug was found by Marco Grassi thanks to syzkaller. Bug 1823317 Bug 1935735 Change-Id: I9bf709b21e5637f338c34d894617f33d84f93ecc Reported-by: Marco Grassi Signed-off-by: Eric Dumazet Signed-off-by: Gagan Grover Reviewed-on: http://git-master/r/1260003 (cherry picked from commit 0c20962647685008dfc6a15fb8a2169ed2abafe6) Reviewed-on: https://git-master.nvidia.com/r/1690290 GVS: Gerrit_Virtual_Submit Reviewed-by: Bibek Basu Tested-by: Amulya Yarlagadda Reviewed-by: Winnie Hsu --- include/net/tcp.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/net/tcp.h b/include/net/tcp.h index 13f12c10f03b..013daf1494ba 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1392,6 +1392,8 @@ static inline void tcp_check_send_head(struct sock *sk, struct sk_buff *skb_unli { if (sk->sk_send_head == skb_unlinked) sk->sk_send_head = NULL; + if (tcp_sk(sk)->highest_sack == skb_unlinked) + tcp_sk(sk)->highest_sack = NULL; } static inline void tcp_init_send_head(struct sock *sk) -- cgit v1.2.3 From 3a956eb7d85eee8bc364545e371a5b2f6a683148 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 29 Jan 2018 17:02:22 -0800 Subject: array_index_nospec: Sanitize speculative array de-references Commit f3804203306e upstream. array_index_nospec() is proposed as a generic mechanism to mitigate against Spectre-variant-1 attacks, i.e. an attack that bypasses boundary checks via speculative execution. The array_index_nospec() implementation is expected to be safe for current generation CPUs across multiple architectures (ARM, x86). Based on an original implementation by Linus Torvalds, tweaked to remove speculative flows by Alexei Starovoitov, and tweaked again by Linus to introduce an x86 assembly implementation for the mask generation. Change-Id: I859161a289215b20bd25ef4006115c0268b30b83 Co-developed-by: Linus Torvalds Co-developed-by: Alexei Starovoitov Suggested-by: Cyril Novikov Signed-off-by: Dan Williams Signed-off-by: Thomas Gleixner Signed-off-by: Will Deacon Cc: linux-arch@vger.kernel.org Cc: kernel-hardening@lists.openwall.com Cc: Peter Zijlstra Cc: Catalin Marinas Cc: Will Deacon Cc: Russell King Cc: gregkh@linuxfoundation.org Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727414229.33451.18411580953862676575.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Jeetesh Burman Reviewed-on: https://git-master.nvidia.com/r/1698396 GVS: Gerrit_Virtual_Submit Reviewed-by: Bibek Basu Tested-by: Bibek Basu --- include/linux/nospec.h | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 include/linux/nospec.h (limited to 'include') diff --git a/include/linux/nospec.h b/include/linux/nospec.h new file mode 100644 index 000000000000..b99bced39ac2 --- /dev/null +++ b/include/linux/nospec.h @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright(c) 2018 Linus Torvalds. All rights reserved. +// Copyright(c) 2018 Alexei Starovoitov. All rights reserved. +// Copyright(c) 2018 Intel Corporation. All rights reserved. + +#ifndef _LINUX_NOSPEC_H +#define _LINUX_NOSPEC_H + +/** + * array_index_mask_nospec() - generate a ~0 mask when index < size, 0 otherwise + * @index: array element index + * @size: number of elements in array + * + * When @index is out of bounds (@index >= @size), the sign bit will be + * set. Extend the sign bit to all bits and invert, giving a result of + * zero for an out of bounds index, or ~0 if within bounds [0, @size). + */ +#ifndef array_index_mask_nospec +static inline unsigned long array_index_mask_nospec(unsigned long index, + unsigned long size) +{ + /* + * Warn developers about inappropriate array_index_nospec() usage. + * + * Even if the CPU speculates past the WARN_ONCE branch, the + * sign bit of @index is taken into account when generating the + * mask. + * + * This warning is compiled out when the compiler can infer that + * @index and @size are less than LONG_MAX. + */ + if (WARN_ONCE(index > LONG_MAX || size > LONG_MAX, + "array_index_nospec() limited to range of [0, LONG_MAX]\n")) + return 0; + + /* + * Always calculate and emit the mask even if the compiler + * thinks the mask is not needed. The compiler does not take + * into account the value of @index under speculation. + */ + OPTIMIZER_HIDE_VAR(index); + return ~(long)(index | (size - 1UL - index)) >> (BITS_PER_LONG - 1); +} +#endif + +/* + * array_index_nospec - sanitize an array index after a bounds check + * + * For a code sequence like: + * + * if (index < size) { + * index = array_index_nospec(index, size); + * val = array[index]; + * } + * + * ...if the CPU speculates past the bounds check then + * array_index_nospec() will clamp the index within the range of [0, + * size). + */ +#define array_index_nospec(index, size) \ +({ \ + typeof(index) _i = (index); \ + typeof(size) _s = (size); \ + unsigned long _mask = array_index_mask_nospec(_i, _s); \ + \ + BUILD_BUG_ON(sizeof(_i) > sizeof(long)); \ + BUILD_BUG_ON(sizeof(_s) > sizeof(long)); \ + \ + _i &= _mask; \ + _i; \ +}) +#endif /* _LINUX_NOSPEC_H */ -- cgit v1.2.3