The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x 5d92c7c566dc76d96e0e19e481d926bbe6631c1e # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024070113-rigor-marauding-3cfe@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

5d92c7c566dc ("ata: libata-core: Fix null pointer dereference on error")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5d92c7c566dc76d96e0e19e481d926bbe6631c1e Mon Sep 17 00:00:00 2001 From: Niklas Cassel cassel@kernel.org Date: Sat, 29 Jun 2024 14:42:11 +0200 Subject: [PATCH] ata: libata-core: Fix null pointer dereference on error

If the ata_port_alloc() call in ata_host_alloc() fails, ata_host_release() will get called.

However, the code in ata_host_release() tries to free ata_port struct members unconditionally, which can lead to the following:

BUG: unable to handle page fault for address: 0000000000003990 PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 10 PID: 594 Comm: (udev-worker) Not tainted 6.10.0-rc5 #44 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:ata_host_release.cold+0x2f/0x6e [libata] Code: e4 4d 63 f4 44 89 e2 48 c7 c6 90 ad 32 c0 48 c7 c7 d0 70 33 c0 49 83 c6 0e 41 RSP: 0018:ffffc90000ebb968 EFLAGS: 00010246 RAX: 0000000000000041 RBX: ffff88810fb52e78 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88813b3218c0 RDI: ffff88813b3218c0 RBP: ffff88810fb52e40 R08: 0000000000000000 R09: 6c65725f74736f68 R10: ffffc90000ebb738 R11: 73692033203a746e R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000011 R15: 0000000000000006 FS: 00007f6cc55b9980(0000) GS:ffff88813b300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000003990 CR3: 00000001122a2000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> ? __die_body.cold+0x19/0x27 ? page_fault_oops+0x15a/0x2f0 ? exc_page_fault+0x7e/0x180 ? asm_exc_page_fault+0x26/0x30 ? ata_host_release.cold+0x2f/0x6e [libata] ? ata_host_release.cold+0x2f/0x6e [libata] release_nodes+0x35/0xb0 devres_release_group+0x113/0x140 ata_host_alloc+0xed/0x120 [libata] ata_host_alloc_pinfo+0x14/0xa0 [libata] ahci_init_one+0x6c9/0xd20 [ahci]

Do not access ata_port struct members unconditionally.

Fixes: 633273a3ed1c ("libata-pmp: hook PMP support and enable it") Cc: stable@vger.kernel.org Reviewed-by: Damien Le Moal dlemoal@kernel.org Reviewed-by: Hannes Reinecke hare@suse.de Reviewed-by: John Garry john.g.garry@oracle.com Link: https://lore.kernel.org/r/20240629124210.181537-7-cassel@kernel.org Signed-off-by: Niklas Cassel cassel@kernel.org

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index efb5195da60c..bdccf4ea251a 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -5517,6 +5517,9 @@ static void ata_host_release(struct kref *kref) for (i = 0; i < host->n_ports; i++) { struct ata_port *ap = host->ports[i];

+ if (!ap) + continue; + kfree(ap->pmp_link); kfree(ap->slave_link); kfree(ap->ncq_sense_buf);