Bug 209037

Summary: lec_seq_next does not update index position
Product: Networking Reporter: Colin Ian King (colin.king)
Component: OtherAssignee: Stephen Hemminger (stephen)
Status: NEW ---    
Severity: low    
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: from at least 2.6.12+ Subsystem:
Regression: No Bisected commit-id:

Description Colin Ian King 2020-08-25 16:10:37 UTC 
Stress-testing /procfs with stress-ng tripped the following warning when reading /proc/net/atm/lec:

[ 7236.344619] seq_file: buggy .next function lec_seq_next [lec] did not update position index
[ 7236.344704] seq_file: buggy .next function lec_seq_next [lec] did not update position index

can be reproduced by seeking on the proc file and reading:

dd if=/proc/net/atm/lec seek=1 of=/dev/stdout bs=1K

the read() also blocks which is not correct either.