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| author | Kees Cook <keescook@chromium.org> | 2020-05-06 11:44:14 -0700 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2020-05-30 10:34:02 -0700 |
| commit | 26961d76ff35aecb1af0fefd283fb5170786a812 (patch) | |
| tree | 254e7b8cd11627877e114e937dcfcaa60fd382b2 /fs/pstore | |
| parent | f858b57f7dd28b5bb55e9dc3776fff58f38a7c91 (diff) | |
| download | lwn-26961d76ff35aecb1af0fefd283fb5170786a812.tar.gz lwn-26961d76ff35aecb1af0fefd283fb5170786a812.zip | |
pstore/ram: Refactor DT size parsing
Refactor device tree size parsing routines to be able to pass a non-zero
default value for providing a configurable default for the coming
"max_reason" field. Also rename the helpers, since we're not always
parsing a size -- we're parsing a u32 and making sure it's not greater
than INT_MAX.
Link: https://lore.kernel.org/lkml/20200506211523.15077-4-keescook@chromium.org/
Link: https://lore.kernel.org/lkml/20200521205223.175957-1-tyhicks@linux.microsoft.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'fs/pstore')
| -rw-r--r-- | fs/pstore/ram.c | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 3b399f72e495..8cdafb686736 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -644,19 +644,25 @@ static int ramoops_init_prz(const char *name, return 0; } -static int ramoops_parse_dt_size(struct platform_device *pdev, - const char *propname, u32 *value) +/* Read a u32 from a dt property and make sure it's safe for an int. */ +static int ramoops_parse_dt_u32(struct platform_device *pdev, + const char *propname, + u32 default_value, u32 *value) { u32 val32 = 0; int ret; ret = of_property_read_u32(pdev->dev.of_node, propname, &val32); - if (ret < 0 && ret != -EINVAL) { + if (ret == -EINVAL) { + /* field is missing, use default value. */ + val32 = default_value; + } else if (ret < 0) { dev_err(&pdev->dev, "failed to parse property %s: %d\n", propname, ret); return ret; } + /* Sanity check our results. */ if (val32 > INT_MAX) { dev_err(&pdev->dev, "%s %u > INT_MAX\n", propname, val32); return -EOVERFLOW; @@ -689,21 +695,22 @@ static int ramoops_parse_dt(struct platform_device *pdev, pdata->mem_type = of_property_read_bool(of_node, "unbuffered"); pdata->dump_oops = !of_property_read_bool(of_node, "no-dump-oops"); -#define parse_size(name, field) { \ - ret = ramoops_parse_dt_size(pdev, name, &value); \ +#define parse_u32(name, field, default_value) { \ + ret = ramoops_parse_dt_u32(pdev, name, default_value, \ + &value); \ if (ret < 0) \ return ret; \ field = value; \ } - parse_size("record-size", pdata->record_size); - parse_size("console-size", pdata->console_size); - parse_size("ftrace-size", pdata->ftrace_size); - parse_size("pmsg-size", pdata->pmsg_size); - parse_size("ecc-size", pdata->ecc_info.ecc_size); - parse_size("flags", pdata->flags); + parse_u32("record-size", pdata->record_size, 0); + parse_u32("console-size", pdata->console_size, 0); + parse_u32("ftrace-size", pdata->ftrace_size, 0); + parse_u32("pmsg-size", pdata->pmsg_size, 0); + parse_u32("ecc-size", pdata->ecc_info.ecc_size, 0); + parse_u32("flags", pdata->flags, 0); -#undef parse_size +#undef parse_u32 /* * Some old Chromebooks relied on the kernel setting the |