Hi Peff
On 29/04/2025 22:51, Jeff King wrote:
On Tue, Apr 29, 2025 at 09:40:13PM +0200, Kristoffer Haugsbakk wrote:
On Tue, Apr 29, 2025, at 11:22, Phillip Wood wrote:
#0 run_git_commit (defmsg=0x555555babe70 "<repo path>/MERGE_MSG", opts=0x7fffffffc070, flags=0) at sequencer.c:1158
Thanks for the backtrace. It would be useful to know what's stored in
opts->ctx->reflog_message at this point if it's not too much trouble
please can you run "print *opts" and "print *opts->ctx" here.
Today I ran on f65182a99e5 (The ninth batch, 2025-04-24) at
sequencer.c:1148. I was never able to reproduce this
`opts->ctx->reflog_message` having a weird value with GDB today. The
reflog was also fine.
Then I ran without GDB and I got the weird reflog that I expected.
Have you tried building with "make SANITIZE=address,undefined"?
This is a wild guess, but since ctx->reflog_message is pointing to a
static strbuf, it could be a use after free if the strbuf is reallocated
due to another call to reflog_message(), but we are still holding the
old pointer via ctx->reflog_message.
Oh, nice insight. I'd forgotten we had callers of reflog_message() that
didn't store the result in ctx->reflog_message. One of those callers is
in do_reset() which due to the way the todo list gets constructed is
likely to be called just before do_merge().
Thanks
Phillip
