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| author | James Morse <james.morse@arm.com> | 2019-01-29 21:48:54 +0300 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-02-08 01:10:45 +0300 |
| commit | f2a681b9160b9c80826b3062e71371cfc82b4863 (patch) | |
| tree | 11986398f2f42320e28409e2dc63bf665f2241ef /drivers/acpi | |
| parent | f2a7e059aa7a6a22a6f4612f31ee29e726a3bfd0 (diff) | |
| download | linux-f2a681b9160b9c80826b3062e71371cfc82b4863.tar.xz | |
ACPI / APEI: Make GHES estatus header validation more user friendly
ghes_read_estatus() checks various lengths in the top-level header to
ensure the CPER records to be read aren't obviously corrupt.
Take the opportunity to make this more user-friendly, printing a
(ratelimited) message about the nature of the header format error.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: James Morse <james.morse@arm.com>
[ rjw: Add missing 'static' ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/apei/ghes.c | 46 |
1 files changed, 32 insertions, 14 deletions
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 54746a791f3f..4fb274bb209e 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -293,6 +293,30 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, } } +/* Check the top-level record header has an appropriate size. */ +static int __ghes_check_estatus(struct ghes *ghes, + struct acpi_hest_generic_status *estatus) +{ + u32 len = cper_estatus_len(estatus); + + if (len < sizeof(*estatus)) { + pr_warn_ratelimited(FW_WARN GHES_PFX "Truncated error status block!\n"); + return -EIO; + } + + if (len > ghes->generic->error_block_length) { + pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid error status block length!\n"); + return -EIO; + } + + if (cper_estatus_check_header(estatus)) { + pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid CPER header!\n"); + return -EIO; + } + + return 0; +} + static int ghes_read_estatus(struct ghes *ghes, struct acpi_hest_generic_status *estatus, u64 *buf_paddr, enum fixed_addresses fixmap_idx) @@ -319,27 +343,21 @@ static int ghes_read_estatus(struct ghes *ghes, return -ENOENT; } - rc = -EIO; + rc = __ghes_check_estatus(ghes, estatus); + if (rc) + return rc; + len = cper_estatus_len(estatus); - if (len < sizeof(*estatus)) - goto err_read_block; - if (len > ghes->generic->error_block_length) - goto err_read_block; - if (cper_estatus_check_header(estatus)) - goto err_read_block; ghes_copy_tofrom_phys(estatus + 1, *buf_paddr + sizeof(*estatus), len - sizeof(*estatus), 1, fixmap_idx); - if (cper_estatus_check(estatus)) - goto err_read_block; - rc = 0; - -err_read_block: - if (rc) + if (cper_estatus_check(estatus)) { pr_warn_ratelimited(FW_WARN GHES_PFX "Failed to read error status block!\n"); + return -EIO; + } - return rc; + return 0; } static void ghes_clear_estatus(struct ghes *ghes, |