In jfs_dmap.c at line 381, BLKTODMAP is used to get a logical block
number inside dbFree(). db_l2nbperpage, which is the log2 number of
blocks per page, is passed as an argument to BLKTODMAP which uses it
for shifting.
Syzbot reported a shift out-of-bounds crash because db_l2nbperpage is
too big. This happens because the large value is set without any
validation in dbMount() at line 181.
Thus, make sure that db_l2nbperpage is correct while mounting.
Reported-and-tested-by: syzbot+d2cd27dcf8e04b232eb2(a)syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=2a70a453331db32ed491f5cbb07e81bf2d2257…
Cc: stable(a)vger.kernel.org
Signed-off-by: Siddh Raman Pant <code(a)siddh.me>
---
fs/jfs/jfs_dmap.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index a3eb1e826947..62f058822a3a 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -178,7 +178,13 @@ int dbMount(struct inode *ipbmap)
dbmp_le = (struct dbmap_disk *) mp->data;
bmp->db_mapsize = le64_to_cpu(dbmp_le->dn_mapsize);
bmp->db_nfree = le64_to_cpu(dbmp_le->dn_nfree);
+
bmp->db_l2nbperpage = le32_to_cpu(dbmp_le->dn_l2nbperpage);
+ if (bmp->db_l2nbperpage > L2MAXL0SIZE) {
+ err = -EINVAL;
+ goto err_release_metapage;
+ }
+
bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag);
if (!bmp->db_numag) {
err = -EINVAL;
--
2.39.2
The patch below does not apply to the 5.4-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(a)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-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 97b6b9cbba40a21c1d9a344d5c1991f8cfbf136e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023061759-gilled-droop-f51d@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 97b6b9cbba40a21c1d9a344d5c1991f8cfbf136e Mon Sep 17 00:00:00 2001
From: Ricardo Ribalda <ribalda(a)chromium.org>
Date: Fri, 19 May 2023 16:47:37 +0200
Subject: [PATCH] x86/purgatory: remove PGO flags
If profile-guided optimization is enabled, the purgatory ends up with
multiple .text sections. This is not supported by kexec and crashes the
system.
Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-2-b05c520b7296@chromium…
Fixes: 930457057abe ("kernel/kexec_file.c: split up __kexec_load_puragory")
Signed-off-by: Ricardo Ribalda <ribalda(a)chromium.org>
Cc: <stable(a)vger.kernel.org>
Cc: Albert Ou <aou(a)eecs.berkeley.edu>
Cc: Baoquan He <bhe(a)redhat.com>
Cc: Borislav Petkov (AMD) <bp(a)alien8.de>
Cc: Christophe Leroy <christophe.leroy(a)csgroup.eu>
Cc: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: Dave Young <dyoung(a)redhat.com>
Cc: Eric W. Biederman <ebiederm(a)xmission.com>
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Michael Ellerman <mpe(a)ellerman.id.au>
Cc: Nathan Chancellor <nathan(a)kernel.org>
Cc: Nicholas Piggin <npiggin(a)gmail.com>
Cc: Nick Desaulniers <ndesaulniers(a)google.com>
Cc: Palmer Dabbelt <palmer(a)dabbelt.com>
Cc: Palmer Dabbelt <palmer(a)rivosinc.com>
Cc: Paul Walmsley <paul.walmsley(a)sifive.com>
Cc: Philipp Rudo <prudo(a)redhat.com>
Cc: Ross Zwisler <zwisler(a)google.com>
Cc: Simon Horman <horms(a)kernel.org>
Cc: Steven Rostedt (Google) <rostedt(a)goodmis.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Tom Rix <trix(a)redhat.com>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
index 82fec66d46d2..42abd6af1198 100644
--- a/arch/x86/purgatory/Makefile
+++ b/arch/x86/purgatory/Makefile
@@ -14,6 +14,11 @@ $(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE
CFLAGS_sha256.o := -D__DISABLE_EXPORTS
+# When profile-guided optimization is enabled, llvm emits two different
+# overlapping text sections, which is not supported by kexec. Remove profile
+# optimization flags.
+KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%,$(KBUILD_CFLAGS))
+
# When linking purgatory.ro with -r unresolved symbols are not checked,
# also link a purgatory.chk binary without -r to check for unresolved symbols.
PURGATORY_LDFLAGS := -e purgatory_start -z nodefaultlib