71 lines
2.5 KiB
Diff
71 lines
2.5 KiB
Diff
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From 6752571d8d782d07537a258a1ec8919ebd1308ad Mon Sep 17 00:00:00 2001
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From: Lianbo Jiang <lijiang@redhat.com>
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Date: Wed, 5 Jun 2024 16:28:58 +0800
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Subject: [PATCH 7/9] X86 64: fix for crash session loading failure
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Kernel commit 223b5e57d0d5 ("mm/execmem, arch: convert remaining
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overrides of module_alloc to execmem") makes crash session loading
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failure as below:
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# ./crash -s
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crash: seek error: kernel virtual address: ffffffff826bb418 type: "page_offset_base"
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For X86 64 architecture, currently crash will search for symbol
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"module_load_offset" to determine if the KASLR is enabled, and go
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into the relevant code block. But the symbols "module_load_offset"
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has been removed since Linux v6.10-rc1, which caused the current
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failure.
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And this issue can occur with live debugging and core dump file
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debugging.
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Let's check the symbol "kaslr_regions" instead of "module_load_offset"
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to fix it.
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Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
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---
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symbols.c | 13 ++++++++-----
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1 file changed, 8 insertions(+), 5 deletions(-)
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diff --git a/symbols.c b/symbols.c
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index 107920f..f3c94b0 100644
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--- a/symbols.c
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+++ b/symbols.c
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@@ -619,9 +619,9 @@ strip_symbol_end(const char *name, char *buf)
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* or in /proc/kallsyms on a live system.
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*
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* Setting KASLR_CHECK will trigger a search for "module_load_offset"
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- * during the initial symbol sort operation, and if found, will
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- * set (RELOC_AUTO|KASLR). On live systems, the search is done
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- * here by checking /proc/kallsyms.
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+ * or "kaslr_regions" during the initial symbol sort operation, and
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+ * if found, will set (RELOC_AUTO|KASLR). On live systems, the search
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+ * is done here by checking /proc/kallsyms.
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*/
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static void
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kaslr_init(void)
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@@ -646,7 +646,8 @@ kaslr_init(void)
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st->_stext_vmlinux = UNINITIALIZED;
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if (ACTIVE() && /* Linux 3.15 */
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- (symbol_value_from_proc_kallsyms("module_load_offset") != BADVAL)) {
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+ ((symbol_value_from_proc_kallsyms("kaslr_regions") != BADVAL) ||
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+ (symbol_value_from_proc_kallsyms("module_load_offset") != BADVAL))) {
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kt->flags2 |= (RELOC_AUTO|KASLR);
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st->_stext_vmlinux = UNINITIALIZED;
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}
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@@ -14251,7 +14252,9 @@ numeric_forward(const void *P_x, const void *P_y)
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st->_stext_vmlinux = valueof(y);
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}
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if (kt->flags2 & KASLR_CHECK) {
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- if (STREQ(x->name, "module_load_offset") ||
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+ if (STREQ(x->name, "kaslr_regions") ||
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+ STREQ(y->name, "kaslr_regions") ||
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+ STREQ(x->name, "module_load_offset") ||
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STREQ(y->name, "module_load_offset")) {
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kt->flags2 &= ~KASLR_CHECK;
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kt->flags2 |= (RELOC_AUTO|KASLR);
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--
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2.40.1
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