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| author |   Jean Delvare <jdelvare@suse.de> | 2017-06-15 13:46:01 +0200 |
|---|---|---|
| committer | Jean Delvare <jdelvare@suse.de> | 2017-06-15 13:46:01 +0200 |
| commit | a814c3597a6b6040e2ef9459748081a6d5b7312d (patch) | |
| tree | 2151e7cb68fdc59acb066c603c311480e8540225 /drivers/firmware | |
| parent | firmware: dmi: Fix permissions of product_family (diff) | |
| download | linux-dev-a814c3597a6b6040e2ef9459748081a6d5b7312d.tar.xz linux-dev-a814c3597a6b6040e2ef9459748081a6d5b7312d.zip | |
firmware: dmi_scan: Check DMI structure length
Before accessing DMI data to record it for later, we should ensure
that the DMI structures are large enough to contain the data in
question.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/dmi_scan.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index fc30249132f5..783041964439 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -178,7 +178,7 @@ static void __init dmi_save_ident(const struct dmi_header *dm, int slot, const char *d = (const char *) dm; const char *p; - if (dmi_ident[slot]) + if (dmi_ident[slot] || dm->length <= string) return; p = dmi_string(dm, d[string]); @@ -191,13 +191,14 @@ static void __init dmi_save_ident(const struct dmi_header *dm, int slot, static void __init dmi_save_uuid(const struct dmi_header *dm, int slot, int index) { - const u8 *d = (u8 *) dm + index; + const u8 *d; char *s; int is_ff = 1, is_00 = 1, i; - if (dmi_ident[slot]) + if (dmi_ident[slot] || dm->length <= index + 16) return; + d = (u8 *) dm + index; for (i = 0; i < 16 && (is_ff || is_00); i++) { if (d[i] != 0x00) is_00 = 0; @@ -228,16 +229,17 @@ static void __init dmi_save_uuid(const struct dmi_header *dm, int slot, static void __init dmi_save_type(const struct dmi_header *dm, int slot, int index) { - const u8 *d = (u8 *) dm + index; + const u8 *d; char *s; - if (dmi_ident[slot]) + if (dmi_ident[slot] || dm->length <= index) return; s = dmi_alloc(4); if (!s) return; + d = (u8 *) dm + index; sprintf(s, "%u", *d & 0x7F); dmi_ident[slot] = s; } @@ -278,9 +280,13 @@ static void __init dmi_save_devices(const struct dmi_header *dm) static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm) { - int i, count = *(u8 *)(dm + 1); + int i, count; struct dmi_device *dev; + if (dm->length < 0x05) + return; + + count = *(u8 *)(dm + 1); for (i = 1; i <= count; i++) { const char *devname = dmi_string(dm, i); @@ -353,6 +359,9 @@ static void __init dmi_save_extended_devices(const struct dmi_header *dm) const char *name; const u8 *d = (u8 *)dm; + if (dm->length < 0x0B) + return; + /* Skip disabled device */ if ((d[0x5] & 0x80) == 0) return; @@ -387,7 +396,7 @@ static void __init save_mem_devices(const struct dmi_header *dm, void *v) const char *d = (const char *)dm; static int nr; - if (dm->type != DMI_ENTRY_MEM_DEVICE) + if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x12) return; if (nr >= dmi_memdev_nr) { pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n"); |