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| author | Jean Delvare <jdelvare@suse.de> | 2024-04-30 18:29:32 +0200 |
|---|---|---|
| committer | Jean Delvare <jdelvare@suse.de> | 2024-04-30 18:29:32 +0200 |
| commit | 0ef11f604503b1862a21597436283f158114d77e (patch) | |
| tree | ddc51254ea3979b08bb67a3662c4e353f2628011 /drivers/firmware/dmi_scan.c | |
| parent | cf770af5645a41a753c55a053fa1237105b0964a (diff) | |
| download | linux-0ef11f604503b1862a21597436283f158114d77e.tar.gz linux-0ef11f604503b1862a21597436283f158114d77e.tar.bz2 linux-0ef11f604503b1862a21597436283f158114d77e.zip | |
firmware: dmi: Stop decoding on broken entry
If a DMI table entry is shorter than 4 bytes, it is invalid. Due to
how DMI table parsing works, it is impossible to safely recover from
such an error, so we have to stop decoding the table.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Link: https://lore.kernel.org/linux-kernel/Zh2K3-HLXOesT_vZ@liuwe-devbox-debian-v2/T/
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Diffstat (limited to 'drivers/firmware/dmi_scan.c')
| -rw-r--r-- | drivers/firmware/dmi_scan.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index 015c95a825d3..ac2a5d2d4746 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -102,6 +102,17 @@ static void dmi_decode_table(u8 *buf, const struct dmi_header *dm = (const struct dmi_header *)data; /* + * If a short entry is found (less than 4 bytes), not only it + * is invalid, but we cannot reliably locate the next entry. + */ + if (dm->length < sizeof(struct dmi_header)) { + pr_warn(FW_BUG + "Corrupted DMI table, offset %zd (only %d entries processed)\n", + data - buf, i); + break; + } + + /* * We want to know the total length (formatted area and * strings) before decoding to make sure we won't run off the * table in dmi_decode or dmi_string |