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 993562FDC55; Tue, 12 Aug 2025 18:47:34 +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=1755024454; cv=none; b=etJ7TAbC7KGfXSObj7MZsncbaF8Utmi6CCKjvmCQraB10wqB/2YsZei8EkoNq6wY4329PBMXCoaK7SCxqUWtHoKRI9PAJhnKWIrvjY6dXGRKPXrXw+TGFoUSFLmEiq0fzUGB83H4BgYyIv4rVRU9se8//zswwvyEyIvUyQurIeg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755024454; c=relaxed/simple; bh=UlYgXNK6mYQA06C6dfB9jC7CQ80GoYkYoncOOAu5aWk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=g1CQ8iIKycnFmeliMuAmEWpKxyc1cafucpNsTb3jagX8gDFIBw5Xs3Z0b+ICw9FV2AjnnhZqeGtIZBK4Y0tNEuBTVWLx1td60XWZcnGigMg8nhZRUFMHOtSmEaMUEL2uSOcD2e3TQwZQ9f86RA2lutYtMA1GGN56F0AeZn1Mph4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FpBlylfp; 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="FpBlylfp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 091AAC4CEF1; Tue, 12 Aug 2025 18:47:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755024454; bh=UlYgXNK6mYQA06C6dfB9jC7CQ80GoYkYoncOOAu5aWk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FpBlylfpYJFYhxrWUdBw9RgiOef5+FnaA7h9JgbG/TU3yZntBkmMX0A6ANnUPI32H LzadSVS3HVny/GrnQLRD7/cLRpISB89XxA/cNRXKUz6n1AIQ19rZex5d59OVaKQ7F4 QxfcS/OIWhDxfGDGt4a8RgES7nLbAU1aFkCcnbwM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, wangzijie , Alexey Dobriyan , Alexei Starovoitov , Al Viro , "Edgecombe, Rick P" , "Kirill A. Shuemov" , Andrew Morton , Sasha Levin Subject: [PATCH 6.16 377/627] proc: use the same treatment to check proc_lseek as ones for proc_read_iter et.al Date: Tue, 12 Aug 2025 19:31:12 +0200 Message-ID: <20250812173433.642373195@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250812173419.303046420@linuxfoundation.org> References: <20250812173419.303046420@linuxfoundation.org> User-Agent: quilt/0.68 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: 8bit 6.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: wangzijie [ Upstream commit ff7ec8dc1b646296f8d94c39339e8d3833d16c05 ] Check pde->proc_ops->proc_lseek directly may cause UAF in rmmod scenario. It's a gap in proc_reg_open() after commit 654b33ada4ab("proc: fix UAF in proc_get_inode()"). Followed by AI Viro's suggestion, fix it in same manner. Link: https://lkml.kernel.org/r/20250607021353.1127963-1-wangzijie1@honor.com Fixes: 3f61631d47f1 ("take care to handle NULL ->proc_lseek()") Signed-off-by: wangzijie Reviewed-by: Alexey Dobriyan Cc: Alexei Starovoitov Cc: Al Viro Cc: "Edgecombe, Rick P" Cc: Kirill A. Shuemov Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin --- fs/proc/generic.c | 2 ++ fs/proc/inode.c | 2 +- fs/proc/internal.h | 5 +++++ include/linux/proc_fs.h | 1 + 4 files changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/proc/generic.c b/fs/proc/generic.c index a3e22803cddf..e0e50914ab25 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -569,6 +569,8 @@ static void pde_set_flags(struct proc_dir_entry *pde) if (pde->proc_ops->proc_compat_ioctl) pde->flags |= PROC_ENTRY_proc_compat_ioctl; #endif + if (pde->proc_ops->proc_lseek) + pde->flags |= PROC_ENTRY_proc_lseek; } struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 3604b616311c..129490151be1 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -473,7 +473,7 @@ static int proc_reg_open(struct inode *inode, struct file *file) typeof_member(struct proc_ops, proc_open) open; struct pde_opener *pdeo; - if (!pde->proc_ops->proc_lseek) + if (!pde_has_proc_lseek(pde)) file->f_mode &= ~FMODE_LSEEK; if (pde_is_permanent(pde)) { diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 96122e91c645..3d48ffe72583 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -99,6 +99,11 @@ static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde) #endif } +static inline bool pde_has_proc_lseek(const struct proc_dir_entry *pde) +{ + return pde->flags & PROC_ENTRY_proc_lseek; +} + extern struct kmem_cache *proc_dir_entry_cache; void pde_free(struct proc_dir_entry *pde); diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index ea62201c74c4..703d0c76cc9a 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -27,6 +27,7 @@ enum { PROC_ENTRY_proc_read_iter = 1U << 1, PROC_ENTRY_proc_compat_ioctl = 1U << 2, + PROC_ENTRY_proc_lseek = 1U << 3, }; struct proc_ops { -- 2.39.5