From: Jia Zhang Date: Fri, 11 Jan 2019 08:59:33 +0000 (+0800) Subject: tpm: Fix off-by-one when reading binary_bios_measurements X-Git-Tag: v5.1-rc1~69^2^2~30 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=64494d39ff630a63b5308042b20132b491e3706b;p=linux.git tpm: Fix off-by-one when reading binary_bios_measurements It is unable to read the entry when it is the only one in binary_bios_measurements: 00000000 00 00 00 00 08 00 00 00 c4 2f ed ad 26 82 00 cb 00000010 1d 15 f9 78 41 c3 44 e7 9d ae 33 20 00 00 00 00 00000020 This is obviously a firmware problem on my linux machine: Manufacturer: Inspur Product Name: SA5212M4 Version: 01 However, binary_bios_measurements should return it any way, rather than nothing, after all its content is completely valid. Fixes: 55a82ab3181b ("tpm: add bios measurement log") Signed-off-by: Jia Zhang Reviewd-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- diff --git a/drivers/char/tpm/eventlog/tpm1.c b/drivers/char/tpm/eventlog/tpm1.c index 4cf830333684..bfdff9271be0 100644 --- a/drivers/char/tpm/eventlog/tpm1.c +++ b/drivers/char/tpm/eventlog/tpm1.c @@ -88,7 +88,7 @@ static void *tpm1_bios_measurements_start(struct seq_file *m, loff_t *pos) event = addr; /* check if current entry is valid */ - if (addr + sizeof(struct tcpa_event) >= limit) + if (addr + sizeof(struct tcpa_event) > limit) return NULL; converted_event_size = @@ -98,7 +98,7 @@ static void *tpm1_bios_measurements_start(struct seq_file *m, loff_t *pos) if (((converted_event_type == 0) && (converted_event_size == 0)) || ((addr + sizeof(struct tcpa_event) + converted_event_size) - >= limit)) + > limit)) return NULL; if (i++ == *pos) @@ -125,7 +125,7 @@ static void *tpm1_bios_measurements_next(struct seq_file *m, void *v, v += sizeof(struct tcpa_event) + converted_event_size; /* now check if current entry is valid */ - if ((v + sizeof(struct tcpa_event)) >= limit) + if ((v + sizeof(struct tcpa_event)) > limit) return NULL; event = v; @@ -134,7 +134,7 @@ static void *tpm1_bios_measurements_next(struct seq_file *m, void *v, converted_event_type = do_endian_conversion(event->event_type); if (((converted_event_type == 0) && (converted_event_size == 0)) || - ((v + sizeof(struct tcpa_event) + converted_event_size) >= limit)) + ((v + sizeof(struct tcpa_event) + converted_event_size) > limit)) return NULL; (*pos)++;