diff options
Diffstat (limited to 'arch/x86/boot')
| -rw-r--r-- | arch/x86/boot/compressed/pgtable_64.c | 13 | ||||
| -rw-r--r-- | arch/x86/boot/string.c | 8 |
2 files changed, 18 insertions, 3 deletions
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index 5f2d03067ae5..c8862696a47b 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -72,6 +72,8 @@ static unsigned long find_trampoline_placement(void) /* Find the first usable memory region under bios_start. */ for (i = boot_params->e820_entries - 1; i >= 0; i--) { + unsigned long new = bios_start; + entry = &boot_params->e820_table[i]; /* Skip all entries above bios_start. */ @@ -84,15 +86,20 @@ static unsigned long find_trampoline_placement(void) /* Adjust bios_start to the end of the entry if needed. */ if (bios_start > entry->addr + entry->size) - bios_start = entry->addr + entry->size; + new = entry->addr + entry->size; /* Keep bios_start page-aligned. */ - bios_start = round_down(bios_start, PAGE_SIZE); + new = round_down(new, PAGE_SIZE); /* Skip the entry if it's too small. */ - if (bios_start - TRAMPOLINE_32BIT_SIZE < entry->addr) + if (new - TRAMPOLINE_32BIT_SIZE < entry->addr) continue; + /* Protect against underflow. */ + if (new - TRAMPOLINE_32BIT_SIZE > bios_start) + break; + + bios_start = new; break; } diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c index 401e30ca0a75..8272a4492844 100644 --- a/arch/x86/boot/string.c +++ b/arch/x86/boot/string.c @@ -37,6 +37,14 @@ int memcmp(const void *s1, const void *s2, size_t len) return diff; } +/* + * Clang may lower `memcmp == 0` to `bcmp == 0`. + */ +int bcmp(const void *s1, const void *s2, size_t len) +{ + return memcmp(s1, s2, len); +} + int strcmp(const char *str1, const char *str2) { const unsigned char *s1 = (const unsigned char *)str1; |