diff options
| author | Guo Weikang <guoweikang.kernel@gmail.com> | 2024-12-12 18:10:00 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-01-13 22:40:59 -0800 |
| commit | ccd582059a132f2bdc3486766ac57c24c465f471 (patch) | |
| tree | 9de895e240d1b4db42a4e2f727265505fb3d5231 /mm/early_ioremap.c | |
| parent | 8ad946eb3df4ca1a243ce412e3e95f03b4468cbe (diff) | |
mm/early_ioremap: add null pointer checks to prevent NULL-pointer dereference
The early_ioremap interface can fail and return NULL in certain cases. To
prevent NULL-pointer dereference crashes, fixed issues in the acpi_extlog
and copy_early_mem interfaces, improving robustness when handling early
memory.
Link: https://lkml.kernel.org/r/20241212101004.1544070-1-guoweikang.kernel@gmail.com
Signed-off-by: Guo Weikang <guoweikang.kernel@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Julian Stecklina <julian.stecklina@cyberus-technology.de>
Cc: Kevin Loughlin <kevinloughlin@google.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/early_ioremap.c')
| -rw-r--r-- | mm/early_ioremap.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/mm/early_ioremap.c b/mm/early_ioremap.c index ce06b2884789..ff35b84a7b50 100644 --- a/mm/early_ioremap.c +++ b/mm/early_ioremap.c @@ -245,7 +245,10 @@ early_memremap_prot(resource_size_t phys_addr, unsigned long size, #define MAX_MAP_CHUNK (NR_FIX_BTMAPS << PAGE_SHIFT) -void __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size) +/* + * If no empty slot, handle that and return -ENOMEM. + */ +int __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size) { unsigned long slop, clen; char *p; @@ -256,12 +259,15 @@ void __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size) if (clen > MAX_MAP_CHUNK - slop) clen = MAX_MAP_CHUNK - slop; p = early_memremap(src & PAGE_MASK, clen + slop); + if (!p) + return -ENOMEM; memcpy(dest, p + slop, clen); early_memunmap(p, clen + slop); dest += clen; src += clen; size -= clen; } + return 0; } #else /* CONFIG_MMU */ |