kernel/linux.git/arch/arm64/lib, branch v5.15.209

arm64: insn: Add support for encoding DSB

2025-06-27T10:05:37+00:00

[ Upstream commit 63de8abd97ddb9b758bd8f915ecbd18e1f1a87a0 ] To generate code in the eBPF epilogue that uses the DSB instruction, insn.c needs a heler to encode the type and domain. Re-use the crm encoding logic from the DMB instruction. Signed-off-by: James Morse Reviewed-by: Catalin Marinas Signed-off-by: Pu Lehui Signed-off-by: Greg Kroah-Hartman

arm64: insn: add encoders for atomic operations

2025-06-27T10:05:36+00:00

[ Upstream commit fa1114d9eba5087ba5e81aab4c56f546995e6cd3 ] It is a preparation patch for eBPF atomic supports under arm64. eBPF needs support atomic[64]_fetch_add, atomic[64]_[fetch_]{and,or,xor} and atomic[64]_{xchg|cmpxchg}. The ordering semantics of eBPF atomics are the same with the implementations in linux kernel. Add three helpers to support LDCLR/LDEOR/LDSET/SWP, CAS and DMB instructions. STADD/STCLR/STEOR/STSET are simply encoded as aliases for LDADD/LDCLR/LDEOR/LDSET with XZR as the destination register, so no extra helper is added. atomic_fetch_add() and other atomic ops needs support for STLXR instruction, so extend enum aarch64_insn_ldst_type to do that. LDADD/LDEOR/LDSET/SWP and CAS instructions are only available when LSE atomics is enabled, so just return AARCH64_BREAK_FAULT directly in these newly-added helpers if CONFIG_ARM64_LSE_ATOMICS is disabled. Signed-off-by: Hou Tao Link: https://lore.kernel.org/r/20220217072232.1186625-3-houtao1@huawei.com Signed-off-by: Will Deacon Signed-off-by: Pu Lehui Signed-off-by: Greg Kroah-Hartman

arm64: csum: Fix OoB access in IP checksum code for negative lengths

2023-09-19T10:22:51+00:00

commit 8bd795fedb8450ecbef18eeadbd23ed8fc7630f5 upstream. Although commit c2c24edb1d9c ("arm64: csum: Fix pathological zero-length calls") added an early return for zero-length input, syzkaller has popped up with an example of a _negative_ length which causes an undefined shift and an out-of-bounds read: | BUG: KASAN: slab-out-of-bounds in do_csum+0x44/0x254 arch/arm64/lib/csum.c:39 | Read of size 4294966928 at addr ffff0000d7ac0170 by task syz-executor412/5975 | | CPU: 0 PID: 5975 Comm: syz-executor412 Not tainted 6.4.0-rc4-syzkaller-g908f31f2a05b #0 | Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 | Call trace: | dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 | show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 | __dump_stack lib/dump_stack.c:88 [inline] | dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 | print_address_description mm/kasan/report.c:351 [inline] | print_report+0x174/0x514 mm/kasan/report.c:462 | kasan_report+0xd4/0x130 mm/kasan/report.c:572 | kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:187 | __kasan_check_read+0x20/0x30 mm/kasan/shadow.c:31 | do_csum+0x44/0x254 arch/arm64/lib/csum.c:39 | csum_partial+0x30/0x58 lib/checksum.c:128 | gso_make_checksum include/linux/skbuff.h:4928 [inline] | __udp_gso_segment+0xaf4/0x1bc4 net/ipv4/udp_offload.c:332 | udp6_ufo_fragment+0x540/0xca0 net/ipv6/udp_offload.c:47 | ipv6_gso_segment+0x5cc/0x1760 net/ipv6/ip6_offload.c:119 | skb_mac_gso_segment+0x2b4/0x5b0 net/core/gro.c:141 | __skb_gso_segment+0x250/0x3d0 net/core/dev.c:3401 | skb_gso_segment include/linux/netdevice.h:4859 [inline] | validate_xmit_skb+0x364/0xdbc net/core/dev.c:3659 | validate_xmit_skb_list+0x94/0x130 net/core/dev.c:3709 | sch_direct_xmit+0xe8/0x548 net/sched/sch_generic.c:327 | __dev_xmit_skb net/core/dev.c:3805 [inline] | __dev_queue_xmit+0x147c/0x3318 net/core/dev.c:4210 | dev_queue_xmit include/linux/netdevice.h:3085 [inline] | packet_xmit+0x6c/0x318 net/packet/af_packet.c:276 | packet_snd net/packet/af_packet.c:3081 [inline] | packet_sendmsg+0x376c/0x4c98 net/packet/af_packet.c:3113 | sock_sendmsg_nosec net/socket.c:724 [inline] | sock_sendmsg net/socket.c:747 [inline] | __sys_sendto+0x3b4/0x538 net/socket.c:2144 Extend the early return to reject negative lengths as well, aligning our implementation with the generic code in lib/checksum.c Cc: Robin Murphy Fixes: 5777eaed566a ("arm64: Implement optimised checksum routine") Reported-by: syzbot+4a9f9820bd8d302e22f7@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000e0e94c0603f8d213@google.com Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: lib: Import latest version of Arm Optimized Routines' strncmp

2023-09-19T10:22:30+00:00

commit 387d828adffcf1eb949f3141079c479793c59aac upstream. Import the latest version of the Arm Optimized Routines strncmp function based on the upstream code of string/aarch64/strncmp.S at commit 189dfefe37d5 from: https://github.com/ARM-software/optimized-routines This latest version includes MTE support. Note that for simplicity Arm have chosen to contribute this code to Linux under GPLv2 rather than the original MIT OR Apache-2.0 WITH LLVM-exception license. Arm is the sole copyright holder for this code. Signed-off-by: Joey Gouly Cc: Robin Murphy Cc: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Acked-by: Mark Rutland Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20220301101435.19327-3-joey.gouly@arm.com Fixes: 020b199bc70d ("arm64: Import latest version of Cortex Strings' strncmp") Reported-by: John Hsu Link: https://lore.kernel.org/all/e9f30f7d5b7d72a3521da31ab2002b49a26f542e.camel@mediatek.com/ Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: mte: DC {GVA,GZVA} shouldn't be used when DCZID_EL0.DZP == 1

2022-01-27T10:03:28+00:00

[ Upstream commit 685e2564daa1493053fcd7f1dbed38b35ee2f3cb ] Currently, mte_set_mem_tag_range() and mte_zero_clear_page_tags() use DC {GVA,GZVA} unconditionally. But, they should make sure that DCZID_EL0.DZP, which indicates whether or not use of those instructions is prohibited, is zero when using those instructions. Use ST{G,ZG,Z2G} instead when DCZID_EL0.DZP == 1. Fixes: 013bb59dbb7c ("arm64: mte: handle tags zeroing at page allocation time") Fixes: 3d0cca0b02ac ("kasan: speed up mte_set_mem_tag_range") Signed-off-by: Reiji Watanabe Link: https://lore.kernel.org/r/20211206004736.1520989-3-reijiw@google.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

arm64: clear_page() shouldn't use DC ZVA when DCZID_EL0.DZP == 1

2022-01-27T10:03:28+00:00

[ Upstream commit f0616abd4e67143b45b04b565839148458857347 ] Currently, clear_page() uses DC ZVA instruction unconditionally. But it should make sure that DCZID_EL0.DZP, which indicates whether or not use of DC ZVA instruction is prohibited, is zero when using the instruction. Use STNP instead when DCZID_EL0.DZP == 1. Fixes: f27bb139c387 ("arm64: Miscellaneous library functions") Signed-off-by: Reiji Watanabe Reviewed-by: Robin Murphy Link: https://lore.kernel.org/r/20211206004736.1520989-2-reijiw@google.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin

arm64: Mitigate MTE issues with str{n}cmp()

2021-09-21T13:50:19+00:00

As with strlen(), the patches importing the updated str{n}cmp() implementations were originally developed and tested before the advent of CONFIG_KASAN_HW_TAGS, and have subsequently revealed not to be MTE-safe. Since in-kernel MTE is still a rather niche case, let it temporarily fall back to the generic C versions for correctness until we can figure out the best fix. Fixes: 758602c04409 ("arm64: Import latest version of Cortex Strings' strcmp") Fixes: 020b199bc70d ("arm64: Import latest version of Cortex Strings' strncmp") Cc: # 5.14.x Reported-by: Branislav Rankov Signed-off-by: Robin Murphy Acked-by: Mark Rutland Link: https://lore.kernel.org/r/34dc4d12eec0adae49b0ac927df642ed10089d40.1631890770.git.robin.murphy@arm.com Signed-off-by: Catalin Marinas

arch: remove compat_alloc_user_space

2021-09-08T22:32:35+00:00

All users of compat_alloc_user_space() and copy_in_user() have been removed from the kernel, only a few functions in sparc remain that can be changed to calling arch_copy_in_user() instead. Link: https://lkml.kernel.org/r/20210727144859.4150043-7-arnd@kernel.org Signed-off-by: Arnd Bergmann Reviewed-by: Christoph Hellwig Cc: Al Viro Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christoph Hellwig Cc: "David S. Miller" Cc: Eric Biederman Cc: Feng Tang Cc: Heiko Carstens Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Michael Ellerman Cc: Paul Mackerras Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

arm64: use func to get function name in pr_err

2021-07-30T15:26:16+00:00

Prefer using '"%s...", __func__' to get current function's name in a debug message. Signed-off-by: Jason Wang Acked-by: Will Deacon Link: https://lore.kernel.org/r/20210726122907.51529-1-wangborong@cdjrlc.com Signed-off-by: Catalin Marinas

arm64: Avoid premature usercopy failure

2021-07-15T16:29:14+00:00

Al reminds us that the usercopy API must only return complete failure if absolutely nothing could be copied. Currently, if userspace does something silly like giving us an unaligned pointer to Device memory, or a size which overruns MTE tag bounds, we may fail to honour that requirement when faulting on a multi-byte access even though a smaller access could have succeeded. Add a mitigation to the fixup routines to fall back to a single-byte copy if we faulted on a larger access before anything has been written to the destination, to guarantee making *some* forward progress. We needn't be too concerned about the overall performance since this should only occur when callers are doing something a bit dodgy in the first place. Particularly broken userspace might still be able to trick generic_perform_write() into an infinite loop by targeting write() at an mmap() of some read-only device register where the fault-in load succeeds but any store synchronously aborts such that copy_to_user() is genuinely unable to make progress, but, well, don't do that... CC: stable@vger.kernel.org Reported-by: Chen Huang Suggested-by: Al Viro Reviewed-by: Catalin Marinas Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/dc03d5c675731a1f24a62417dba5429ad744234e.1626098433.git.robin.murphy@arm.com Signed-off-by: Will Deacon