From: Vasily Averin Date: Tue, 25 Feb 2020 06:26:08 +0000 (+0300) Subject: tpm: tpm1_bios_measurements_next should increase position index X-Git-Tag: io_uring-5.7-2020-04-09~53^2~8 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=d7a47b96ed1102551eb7325f97937e276fb91045;p=linux-2.6-block.git tpm: tpm1_bios_measurements_next should increase position index If .next function does not change position index, following .show function will repeat output related to current position index. In case of /sys/kernel/security/tpm0/ascii_bios_measurements and binary_bios_measurements: 1) read after lseek beyound end of file generates whole last line. 2) read after lseek to middle of last line generates expected end of last line and unexpected whole last line once again. Cc: stable@vger.kernel.org # 4.19.x Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Reviewed-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 739b1d9d16b6..2c96977ad080 100644 --- a/drivers/char/tpm/eventlog/tpm1.c +++ b/drivers/char/tpm/eventlog/tpm1.c @@ -115,6 +115,7 @@ static void *tpm1_bios_measurements_next(struct seq_file *m, void *v, u32 converted_event_size; u32 converted_event_type; + (*pos)++; converted_event_size = do_endian_conversion(event->event_size); v += sizeof(struct tcpa_event) + converted_event_size; @@ -132,7 +133,6 @@ static void *tpm1_bios_measurements_next(struct seq_file *m, void *v, ((v + sizeof(struct tcpa_event) + converted_event_size) > limit)) return NULL; - (*pos)++; return v; }