From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A3FB7151CDC; Tue, 20 Feb 2024 21:42:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708465333; cv=none; b=Zj59fNa+O8jYmdTnzZSaYZRSh4nQeDHRd3ncBiSTXwNG5UJQ4q9rGFnEFVs/62Ef8M9r8MBFk19u9ahfU1x+WwSuiskeDqgi8jGh0mApP212IZ50uttdWkfBLqQuz/XUKmBX1swNhjVVyUg0mGQUcq/UbLPdOZxB6QMAyMfFfbw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708465333; c=relaxed/simple; bh=M2tB6csEdpVv7xUAVElVt+hJLfOmM8cXKkoAI5mu7Vg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TGEDkJ64WcL+rwyGf5mliLwP6QDF1n/7i0niqjwTVzjH3Ygj4bGIBa3WMg2IFEeqRoyddHDOmQx5t30HWMesSZe/uwwSlS0Ia/a7WRN2B3cIq6eOOi/hUQ+laC2tETk06uxoueeHs8RioTTBlbmVMh4KjccMtYOlGL2xInGXl9A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Eo2McBJa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Eo2McBJa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 11679C433C7; Tue, 20 Feb 2024 21:42:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1708465333; bh=M2tB6csEdpVv7xUAVElVt+hJLfOmM8cXKkoAI5mu7Vg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Eo2McBJarXPVAqUVO0rugWnopdmtLA05/dW5Jyt5JUC3PNe8CepT+bW179avNTwVD S/O8StBT4AzxcT2yflhFQEMtBLy/Cu8JZJxCb4V4pYO9nKtySgfofaRIJBOVRnkyKb mIdPjLdY3ZxIpN5AoKWghJ5OPa7tGHNG4UiiCoHA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Michal Hocko , Oscar Salvador , Muchun Song , Andrew Morton Subject: [PATCH 6.7 289/309] fs,hugetlb: fix NULL pointer dereference in hugetlbs_fill_super Date: Tue, 20 Feb 2024 21:57:28 +0100 Message-ID: <20240220205642.151417459@linuxfoundation.org> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20240220205633.096363225@linuxfoundation.org> References: <20240220205633.096363225@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 6.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oscar Salvador commit 79d72c68c58784a3e1cd2378669d51bfd0cb7498 upstream. When configuring a hugetlb filesystem via the fsconfig() syscall, there is a possible NULL dereference in hugetlbfs_fill_super() caused by assigning NULL to ctx->hstate in hugetlbfs_parse_param() when the requested pagesize is non valid. E.g: Taking the following steps: fd =3D fsopen("hugetlbfs", FSOPEN_CLOEXEC); fsconfig(fd, FSCONFIG_SET_STRING, "pagesize", "1024", 0); fsconfig(fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0); Given that the requested "pagesize" is invalid, ctxt->hstate will be replac= ed with NULL, losing its previous value, and we will print an error: ... ... case Opt_pagesize: ps =3D memparse(param->string, &rest); ctx->hstate =3D h; if (!ctx->hstate) { pr_err("Unsupported page size %lu MB\n", ps / SZ_1M); return -EINVAL; } return 0; ... ... This is a problem because later on, we will dereference ctxt->hstate in hugetlbfs_fill_super() ... ... sb->s_blocksize =3D huge_page_size(ctx->hstate); ... ... Causing below Oops. Fix this by replacing cxt->hstate value only when then pagesize is known to be valid. kernel: hugetlbfs: Unsupported page size 0 MB kernel: BUG: kernel NULL pointer dereference, address: 0000000000000028 kernel: #PF: supervisor read access in kernel mode kernel: #PF: error_code(0x0000) - not-present page kernel: PGD 800000010f66c067 P4D 800000010f66c067 PUD 1b22f8067 PMD 0 kernel: Oops: 0000 [#1] PREEMPT SMP PTI kernel: CPU: 4 PID: 5659 Comm: syscall Tainted: G E 6.8.0-= rc2-default+ #22 5a47c3fef76212addcc6eb71344aabc35190ae8f kernel: Hardware name: Intel Corp. GROVEPORT/GROVEPORT, BIOS GVPRCRB1.86B.= 0016.D04.1705030402 05/03/2017 kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 = 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 2= 8 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400 kernel: FS: 00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:000000= 0000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0 kernel: Call Trace: kernel: kernel: ? __die_body+0x1a/0x60 kernel: ? page_fault_oops+0x16f/0x4a0 kernel: ? search_bpf_extables+0x65/0x70 kernel: ? fixup_exception+0x22/0x310 kernel: ? exc_page_fault+0x69/0x150 kernel: ? asm_exc_page_fault+0x22/0x30 kernel: ? __pfx_hugetlbfs_fill_super+0x10/0x10 kernel: ? hugetlbfs_fill_super+0xb4/0x1a0 kernel: ? hugetlbfs_fill_super+0x28/0x1a0 kernel: ? __pfx_hugetlbfs_fill_super+0x10/0x10 kernel: vfs_get_super+0x40/0xa0 kernel: ? __pfx_bpf_lsm_capable+0x10/0x10 kernel: vfs_get_tree+0x25/0xd0 kernel: vfs_cmd_create+0x64/0xe0 kernel: __x64_sys_fsconfig+0x395/0x410 kernel: do_syscall_64+0x80/0x160 kernel: ? syscall_exit_to_user_mode+0x82/0x240 kernel: ? do_syscall_64+0x8d/0x160 kernel: ? syscall_exit_to_user_mode+0x82/0x240 kernel: ? do_syscall_64+0x8d/0x160 kernel: ? exc_page_fault+0x69/0x150 kernel: entry_SYSCALL_64_after_hwframe+0x6e/0x76 kernel: RIP: 0033:0x7ffbc0cb87c9 kernel: Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 48 89 f8 = 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 0= 1 f0 ff ff 73 01 c3 48 8b 0d 97 96 0d 00 f7 d8 64 89 01 48 kernel: RSP: 002b:00007ffc29d2f388 EFLAGS: 00000206 ORIG_RAX: 000000000000= 01af kernel: RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffbc0cb87c9 kernel: RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 kernel: RBP: 00007ffc29d2f3b0 R08: 0000000000000000 R09: 0000000000000000 kernel: R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 kernel: R13: 00007ffc29d2f4c0 R14: 0000000000000000 R15: 0000000000000000 kernel: kernel: Modules linked in: rpcsec_gss_krb5(E) auth_rpcgss(E) nfsv4(E) dns_= resolver(E) nfs(E) lockd(E) grace(E) sunrpc(E) netfs(E) af_packet(E) bridge= (E) stp(E) llc(E) iscsi_ibft(E) iscsi_boot_sysfs(E) intel_rapl_msr(E) intel= _rapl_common(E) iTCO_wdt(E) intel_pmc_bxt(E) sb_edac(E) iTCO_vendor_support= (E) x86_pkg_temp_thermal(E) intel_powerclamp(E) coretemp(E) kvm_intel(E) rf= kill(E) ipmi_ssif(E) kvm(E) acpi_ipmi(E) irqbypass(E) pcspkr(E) igb(E) ipmi= _si(E) mei_me(E) i2c_i801(E) joydev(E) intel_pch_thermal(E) i2c_smbus(E) dc= a(E) lpc_ich(E) mei(E) ipmi_devintf(E) ipmi_msghandler(E) acpi_pad(E) tiny_= power_button(E) button(E) fuse(E) efi_pstore(E) configfs(E) ip_tables(E) x_= tables(E) ext4(E) mbcache(E) jbd2(E) hid_generic(E) usbhid(E) sd_mod(E) t10= _pi(E) crct10dif_pclmul(E) crc32_pclmul(E) crc32c_intel(E) polyval_clmulni(= E) ahci(E) xhci_pci(E) polyval_generic(E) gf128mul(E) ghash_clmulni_intel(E= ) sha512_ssse3(E) sha256_ssse3(E) xhci_pci_renesas(E) libahci(E) ehci_pci(E= ) sha1_ssse3(E) xhci_hcd(E) ehci_hcd(E) libata(E) kernel: mgag200(E) i2c_algo_bit(E) usbcore(E) wmi(E) sg(E) dm_multipath(E= ) dm_mod(E) scsi_dh_rdac(E) scsi_dh_emc(E) scsi_dh_alua(E) scsi_mod(E) scsi= _common(E) aesni_intel(E) crypto_simd(E) cryptd(E) kernel: Unloaded tainted modules: acpi_cpufreq(E):1 fjes(E):1 kernel: CR2: 0000000000000028 kernel: ---[ end trace 0000000000000000 ]--- kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 = 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 2= 8 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400 kernel: FS: 00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:000000= 0000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0 Link: https://lkml.kernel.org/r/20240130210418.3771-1-osalvador@suse.de Fixes: 32021982a324 ("hugetlbfs: Convert to fs_context") Signed-off-by: Michal Hocko Signed-off-by: Oscar Salvador Acked-by: Muchun Song Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- fs/hugetlbfs/inode.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -1354,6 +1354,7 @@ static int hugetlbfs_parse_param(struct { struct hugetlbfs_fs_context *ctx =3D fc->fs_private; struct fs_parse_result result; + struct hstate *h; char *rest; unsigned long ps; int opt; @@ -1398,11 +1399,12 @@ static int hugetlbfs_parse_param(struct =20 case Opt_pagesize: ps =3D memparse(param->string, &rest); - ctx->hstate =3D size_to_hstate(ps); - if (!ctx->hstate) { + h =3D size_to_hstate(ps); + if (!h) { pr_err("Unsupported page size %lu MB\n", ps / SZ_1M); return -EINVAL; } + ctx->hstate =3D h; return 0; =20 case Opt_min_size: