On Mon, Jul 03, 2023 at 05:53:48AM +0200, Mirsad Goran Todorovac wrote: > On 7/3/23 05:26, Guenter Roeck wrote: > > On 7/2/23 20:20, Kees Cook wrote: > > > On Mon, Jul 03, 2023 at 08:44:37AM +0700, Bagas Sanjaya wrote: > > > > On Sun, Jul 02, 2023 at 06:36:12PM +0200, Mirsad Goran Todorovac wrote: > > > > > Hi, > > > > > > > > > > After new git pull the kernel in Torvalds tree with default debug config > > > > > failed to boot with error that occurs prior to mounting filesystems, so there > > > > > is no log safe for the screenshot(s) here: > > > > > > > > > > [1] https://domac.alu.unizg.hr/~mtodorov/linux/crashes/2023-07-02/ > > > > > > > > > > Bisect shows the first bad commit is 2d47c6956ab3 (v6.4-rc2-1-g2d47c6956ab3): > > > > > > > > > > # good: [98be618ad03010b1173fc3c35f6cbb4447ee2b07] Merge tag 'Smack-for-6.5' of https://github.com/cschaufler/smack-next > > > > > git bisect good 98be618ad03010b1173fc3c35f6cbb4447ee2b07 > > > > > # bad: [f4a0659f823e5a828ea2f45b4849ea8e2dd2984c] drm/i2c: tda998x: Replace all non-returning strlcpy with strscpy > > > > > git bisect bad f4a0659f823e5a828ea2f45b4849ea8e2dd2984c > > > > > . > > > > > . > > > > > . > > > > > # bad: [2d47c6956ab3c8b580a59d7704aab3e2a4882b6c] ubsan: Tighten UBSAN_BOUNDS on GCC > > > > > git bisect bad 2d47c6956ab3c8b580a59d7704aab3e2a4882b6c > > > > > # first bad commit: [2d47c6956ab3c8b580a59d7704aab3e2a4882b6c] ubsan: Tighten UBSAN_BOUNDS on GCC > > > > > > > > > > The architecture is Ubuntu 22.04 with lshw and config give in the attachment. > > > > > > > > Can you show early kernel log (something like dmesg)? > > > > > > > > Anyway, I'm adding it to regzbot: > > > > > > > > #regzbot ^introduced: 2d47c6956ab3c8 > > > > #regzbot title: Linux kernel fails to boot due to UBSAN_BOUNDS tightening > > > > > > I'm confused. Commit 2d47c6956ab3c8b580a59d7704aab3e2a4882b6c isn't in the v6.4 > > > tree... it's only in Linus's ToT. > > > > > > > In ToT: > > > > $ git describe 2d47c6956ab3 > > v6.4-rc2-1-g2d47c6956ab3 > > > > $ git describe --contains 2d47c6956ab3 > > next-20230616~2^2~51 > > $ git describe --contains --match 'v*' 2d47c6956ab3 > > fatal: cannot describe '2d47c6956ab3c8b580a59d7704aab3e2a4882b6c' > > > > "git describe" always shows the parent tree, which I guess was based on > > v6.4-rc2. > > > > Guenter > > > > > > > Also, the config you included does not show CONFIG_UBSAN_BOUNDS_STRICT > > > as even being available, much less present. Something seems very wrong > > > with this report... > > > > > > -Kees > > Anyway, I have double checked and linux-image-6.4.0-rc2-crash boots while > linux-image-6.4.0-rc2-crash-00001-g2d47c6956ab3 freezes in early boot. I don't understand what tree you're testing. 2d47c6956ab3 is only in Linus's latest tree, which is not 6.4-rc2. If you're testing Linus's tree, and you're bisecting to 2d47c6956ab3, I don't understand why the .config you sent doesn't include CONFIG_UBSAN_BOUNDS_STRICT (which was introduced by that commit) -- it should be visible whether or not it is selected. > Of course, in the next boot dmesg appears overwritten ... I could provide > only the first screen screenshots. Without CONFIG_UBSAN_TRAP, I would not expect anything other than a warning (i.e. boot would continue). The only other thing I can think of that seems related (the backtrace appears to show usb), might be this: https://lore.kernel.org/lkml/20230629190900.never.787-kees@xxxxxxxxxx/ which won't appears until after v6.5-rc1. > The difference is only one commit. > > It is a bit strange so I am available for any additional diagnostics. Thanks! Can you send "grep UBSAN .config" output for the crashing kernel? Are you booting on an EFI-capable machine? If you could configure pstore to use the EFI-vars backend, you can capture the crash in EFI and pstorefs will show it after the next boot. (If you're using systemd, this all may already be happening -- check /var/lib/systemd/pstore/ or see[1] for more details.) -Kees [1] https://www.freedesktop.org/software/systemd/man/systemd-pstore.service.html -- Kees Cook
