diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-25 15:55:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-25 15:55:03 -0700 |
| commit | 75467f60a3d14f08f86f2b353298d2826382ff23 (patch) | |
| tree | acd8a7d5b5a675042449386efa5b42ec44d8bf81 /arch/arm/lib/memset.S | |
| download | linux-stable-75467f60a3d14f08f86f2b353298d2826382ff23.tar.gz linux-stable-75467f60a3d14f08f86f2b353298d2826382ff23.zip | |
Merge tag 'ipe-pr-20260925' of git://git.kernel.org/pub/scm/linux/kernel/git/wufan/ipegrafted
Pull IPE fixes from Fan Wu:
"Two fixes for use-after-free issues found by recent LLM-assisted code
analysis.
- move successful policy load auditing under the new policy
directory's inode lock, preventing a concurrent policy deletion
from freeing the policy while it is still being audited
- protect the dm-verity root hash with RCU, preventing policy
evaluation from racing with root hash replacement during preresume"
* tag 'ipe-pr-20260925' of git://git.kernel.org/pub/scm/linux/kernel/git/wufan/ipe:
ipe: protect the dm-verity root hash with RCU
ipe: fix use-after-free when auditing a newly loaded policy
Diffstat (limited to 'arch/arm/lib/memset.S')
| -rw-r--r-- | arch/arm/lib/memset.S | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/arch/arm/lib/memset.S b/arch/arm/lib/memset.S new file mode 100644 index 000000000..de75ae4d5 --- /dev/null +++ b/arch/arm/lib/memset.S @@ -0,0 +1,148 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/lib/memset.S + * + * Copyright (C) 1995-2000 Russell King + * + * ASM optimised string functions + */ +#include <linux/linkage.h> +#include <asm/assembler.h> +#include <asm/unwind.h> + + .text + .align 5 + +ENTRY(__memset) +ENTRY(mmioset) +WEAK(memset) +UNWIND( .fnstart ) + and r1, r1, #255 @ cast to unsigned char + ands r3, r0, #3 @ 1 unaligned? + mov ip, r0 @ preserve r0 as return value + bne 6f @ 1 +/* + * we know that the pointer in ip is aligned to a word boundary. + */ +1: orr r1, r1, r1, lsl #8 + orr r1, r1, r1, lsl #16 + mov r3, r1 +7: cmp r2, #16 + blt 4f +UNWIND( .fnend ) + +#if ! CALGN(1)+0 + +/* + * We need 2 extra registers for this loop - use r8 and the LR + */ +UNWIND( .fnstart ) +UNWIND( .save {r8, lr} ) + stmfd sp!, {r8, lr} + mov r8, r1 + mov lr, r3 + +2: subs r2, r2, #64 + stmiage ip!, {r1, r3, r8, lr} @ 64 bytes at a time. + stmiage ip!, {r1, r3, r8, lr} + stmiage ip!, {r1, r3, r8, lr} + stmiage ip!, {r1, r3, r8, lr} + bgt 2b + ldmfdeq sp!, {r8, pc} @ Now <64 bytes to go. +/* + * No need to correct the count; we're only testing bits from now on + */ + tst r2, #32 + stmiane ip!, {r1, r3, r8, lr} + stmiane ip!, {r1, r3, r8, lr} + tst r2, #16 + stmiane ip!, {r1, r3, r8, lr} + ldmfd sp!, {r8, lr} +UNWIND( .fnend ) + +#else + +/* + * This version aligns the destination pointer in order to write + * whole cache lines at once. + */ + +UNWIND( .fnstart ) +UNWIND( .save {r4-r8, lr} ) + stmfd sp!, {r4-r8, lr} + mov r4, r1 + mov r5, r3 + mov r6, r1 + mov r7, r3 + mov r8, r1 + mov lr, r3 + + cmp r2, #96 + tstgt ip, #31 + ble 3f + + and r8, ip, #31 + rsb r8, r8, #32 + sub r2, r2, r8 + movs r8, r8, lsl #(32 - 4) + stmiacs ip!, {r4, r5, r6, r7} + stmiami ip!, {r4, r5} + tst r8, #(1 << 30) + mov r8, r1 + strne r1, [ip], #4 + +3: subs r2, r2, #64 + stmiage ip!, {r1, r3-r8, lr} + stmiage ip!, {r1, r3-r8, lr} + bgt 3b + ldmfdeq sp!, {r4-r8, pc} + + tst r2, #32 + stmiane ip!, {r1, r3-r8, lr} + tst r2, #16 + stmiane ip!, {r4-r7} + ldmfd sp!, {r4-r8, lr} +UNWIND( .fnend ) + +#endif + +UNWIND( .fnstart ) +4: tst r2, #8 + stmiane ip!, {r1, r3} + tst r2, #4 + strne r1, [ip], #4 +/* + * When we get here, we've got less than 4 bytes to set. We + * may have an unaligned pointer as well. + */ +5: tst r2, #2 + strbne r1, [ip], #1 + strbne r1, [ip], #1 + tst r2, #1 + strbne r1, [ip], #1 + ret lr + +6: subs r2, r2, #4 @ 1 do we have enough + blt 5b @ 1 bytes to align with? + cmp r3, #2 @ 1 + strblt r1, [ip], #1 @ 1 + strble r1, [ip], #1 @ 1 + strb r1, [ip], #1 @ 1 + add r2, r2, r3 @ 1 (r2 = r2 - (4 - r3)) + b 1b +UNWIND( .fnend ) +ENDPROC(memset) +ENDPROC(mmioset) +ENDPROC(__memset) + +ENTRY(__memset32) +UNWIND( .fnstart ) + mov r3, r1 @ copy r1 to r3 and fall into memset64 +UNWIND( .fnend ) +ENDPROC(__memset32) +ENTRY(__memset64) +UNWIND( .fnstart ) + mov ip, r0 @ preserve r0 as return value + b 7b @ jump into the middle of memset +UNWIND( .fnend ) +ENDPROC(__memset64) |
