vasilito
068a1ca63e
Bootloader fork rebase:
- Base changed from 0.1.0 pre-patched archive to upstream 1.0.0 tag (c7eeb9f)
- Applied 0001-redbear-local-forks.patch (Cargo.toml crate path redirects)
- Applied fix-uefi-alloc-panic.patch equivalents (4 panic!() -> graceful
error handling in src/main.rs)
- Applied P5-live-preload-cap-1gib.patch (1 GiB cap on live image preload)
- Skipped: P0 GPT partition scan (requires new module + integration),
P1 timeout/default-resolution, P2 live preload guard (subsumed by
panic fixes + cap), P3 live image safe read, P4 large ISO boot,
redox.patch — to be applied in dedicated rebase session.
firmware-loader/Cargo.toml: version 0.1.0 -> 0.3.0 (sync with other
Red Bear custom crates which are at 0.3.0).
fork-upstream-map.toml: bootloader back from PENDING_REBASE to 1.0.0
since the partial rebase matches upstream 1.0.0 content.
fork-upstream-map.toml: base restored to 'main' tracked (was correctly
tracked by build-redbear.sh).
67 lines
2.2 KiB
C
67 lines
2.2 KiB
C
/* Some auxiliary stuff for defining an alternate stack.
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Copyright (C) 2010-2025 Free Software Foundation, Inc.
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>. */
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/* Written by Eric Blake and Bruno Haible. */
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#include <stdint.h> /* uintptr_t */
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#include <string.h> /* for memset */
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#define MYSTACK_SIZE (1 << 24)
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/* glibc says: Users should use SIGSTKSZ as the size of user-supplied
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buffers. We want to detect stack overflow of the alternate stack
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in a nicer manner than just crashing, so we overallocate in
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comparison to what we hand libsigsegv. Also, we intentionally hand
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an unaligned pointer, to ensure the alternate stack still ends up
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aligned. */
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#define MYSTACK_CRUMPLE_ZONE 8192
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static char mystack_storage[MYSTACK_SIZE + 2 * MYSTACK_CRUMPLE_ZONE + 31];
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static char *mystack; /* MYSTACK_SIZE bytes in the middle of storage. */
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static void
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prepare_alternate_stack (void)
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{
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#ifdef SIGSTKSZ
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if (MYSTACK_SIZE < SIGSTKSZ)
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{
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size_t size = SIGSTKSZ;
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printf ("SIGSTKSZ=%zu exceeds MYSTACK_SIZE=%d\n", size, MYSTACK_SIZE);
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exit (1);
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}
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#endif
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memset (mystack_storage, 's', sizeof mystack_storage);
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mystack = (char *) ((uintptr_t) (mystack_storage + MYSTACK_CRUMPLE_ZONE) | 31);
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}
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static void
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check_alternate_stack_no_overflow (void)
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{
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unsigned int i;
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for (i = MYSTACK_CRUMPLE_ZONE; i > 0; i--)
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if (*(mystack - i) != 's')
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{
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printf ("Alternate stack was exceeded by %u bytes!!\n", i);
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exit (1);
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}
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for (i = MYSTACK_CRUMPLE_ZONE; i > 0; i--)
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if (*(mystack + MYSTACK_SIZE - 1 + i) != 's')
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{
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printf ("Alternate stack was exceeded by %u bytes!!\n", i);
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exit (1);
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}
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}
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